nasa scientific and technical aerospace reports phần 7 pps

A.; Khoo, C.; Benelli, K.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English;See also 20050169945; Original contains color and black and white illustrations; Copyright

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20050170004 Jet Propulsion Lab., California Inst of Tech., Pasadena, CA, USA

Elastic Thickness Estimates for Coronae Associated with Chasmata on Venus

Hoogenboom, T.; Martin, P.; Housean, G A.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also20050169945; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI

on CD-ROM only as part of the entire parent document

Coronae are large-scale circular tectonic features surrounded by annular ridges They are generally considered unique toVenus and may offer insights into the differences in lithospheric structure or mantle convective pattern between Venus andEarth 68% of all coronae are associated with chasmata or fracture belts The remaining 32% are located at volcanic rises or

in the plains Chasmata are linear to arcuate troughs, with trough parallel fractures and faults which extend for 1000 s ofkilometers Estimates of the elastic thickness of the lithosphere (T(sub e)) have been calculated in a number ofgravity/topography studies of Venus and for coronae specifically None of these studies, however, have explored thedependence of T(sub e) on the tectonic history of the region, as implied from the interpretation of relative timing relationshipsbetween coronae and surrounding features We examine the relationship between the local T(sub e) and the relative ages ofcoronae and chasmata with the aim of further constraining the origin and evolution of coronae and chasmata systems.Derived from text

Coronas; Planetary Geology; Venus (Planet); Tectonics; Thickness; Elastic Properties; Landforms; Topography

20050170005 Los Alamos National Lab., NM, USA

LIBS-based Detection of Geological Samples at Low Pressures (\h0.0001 torr) for Moon and Asteroid Exploration

Harris, R D.; Cremers, D A.; Khoo, C.; Benelli, K.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English;See also 20050169945; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

LIBS is under development for future use on surface probes to Mars [1-3] Under simulated Mars atmosphericcomposition and pressure (7 torr, predominately CO2), LIBS has been shown useful for qualitative and quantitative analysis

of geological samples at close and stand-off distances (19 m) Because of its many advantages compared to previouslydeployed and current in-use methods of elemental analysis (e.g x-ray fluorescence, APXS), LIBS has potential for application

to other planetary bodies Of particular interest are the Moon and asteroids having very low ambient gas pressures at thesurface Because the laser plasma used by LIBS is sensitive to the surrounding atmosphere, it is important to determineanalysis capabilities under these conditions The results of a study of LIBS capabilities at low pressure is presented here forboth in-situ and stand-off analysis Plasma light, collected through the evacuated tube by a 10 cm diameter quartz lens, wasfocused onto a fiber optic cable The light was directed into either the

Derived from text

Laser-Induced Breakdown Spectroscopy; Mars Atmosphere; Qualitative Analysis; Quantitative Analysis; Geology; Asteroids; Moon; Atmospheric Composition; Chemical Analysis

20050170006 Collegium Budapest/Inst for Advanced Study, Budapest, Hungary

Annual Change of Martian DDS-Seepages

Horvaith, A.; Kereszturi, A.; Berezi, Sz.; Sik, A.; Pocs, T.; Gesztesi, A.; Ganti, T.; Szathmary, E.; Lunar and Planetary ScienceXXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945; Original contains color and black and white illustrations;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentThe signs of surface water found by MGS (on MOC images), Mars Odyssey (neutron data) and Mars Express (spectraldata) play important role in understanding surface processes especially probable life forms on Mars There are signs of recentliquid water on Mars like the gullies formed probably during high obliquity and dark slope streaks which could be formed bygravitational mass movements or water seepage We discovered and analysed a possible third group of phenomena presumablyproduced by liquid water on the surface, called DDS-seepage These are originated at dark dune spots (DDS) (Dark dune spotsappear in the defrosting surface in late winter early spring in the polar regions of Mars) Most of the DDS-seepages can befound at the steep slopes of the dark dunes in craters and the intercrater areas and we could study not only great number ofthese seepages but also could observe their changes from one Martian year to the other

Derived from text

Dunes; Seepage; Mars Surface; Extraterrestrial Life; Annual Variations

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20050170007 Brown Univ., Providence, RI, USA

Regional Mid-Latitude Late Amazonian Valley Glaciers on Mars: Origin of Lineated Valley Fill and Implications for Recent Climate Change

Head, James W.; Marchant, David r.; Agnew, Marshall C.; Fassett, Caleb I.; Kreslavsky, Mikhail A.; Lunar and PlanetaryScience XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945; Original contains color and black and whiteillustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parentdocument

Among the hallmark morphologies of the highland-lowland boundary region in the northern mid-latitude Protonilus Mensae area (30-50oN, 315-350oW) is the fretted terrain (1), consisting of 1) debris aprons that surround many

Deuteronilus-of the massifs and valley walls, and 2) lineated valley fill (LVF) that occurs on the floors Deuteronilus-of many Deuteronilus-of the valleys (2-14) Theages of these deposits are typically much younger than the adjacent plateau terrain or its breakup and the formation of thevalleys themselves (e.g., 9, 14) The margins of the debris aprons consist of rounded and convex upward topography, and atViking resolution the debris aprons and the valley fill can appear smooth and relatively homogeneous or, in contrast, can becharacterized by closely spaced parallel ridges and grooves a few to several tens of meters high These sets of parallel ridgeshave been interpreted to have formed both parallel and normal to valley and mesa walls Some workers (e.g., 2) argue thatthe lineations form mostly normal to flow due to converging flow from debris aprons on opposite sides of valleys or mesas,while others (e.g., 4) argue that bending of ridges and grooves entering valleys from a side tributary supports flow in thedirection parallel to the valley Recent analysis shows variable downslope gradients suggesting that lateral flow was minimal(e.g., 11) All agree that the materials represent some sort of viscous flow processes, but opinions differ on the details of themechanism; most authors call on processes of gravity-driven debris flow, assisted by ice or water in the interstices derivedfrom either groundwater or diffusive exchange with the atmosphere (e.g., see 7, 10, 13-14) Some liken the process torock-glacial flow (e.g., 2, 4) with the source of the lubricating agent being ice from atmospheric frost deposition and diffusion(2) or mobilized interstitial ground ice (4)

Derived from text

Climate Change; Glaciers; Mars Surface; Valleys; Highlands

20050170008 Lunar and Planetary Inst., Houston, TX, USA

Loss Tangent Map of the Martian Surface: A Frequency Dependent Model for the Near Equatorial Regions

Heggy, E.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945; Original containscolor illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

The complex dielectric properties of the Martian surface sediments are a key parameter to understand the physical andgeometrical parameters (such as density and roughness) of the Martian surface In order to give an experimental description

of the electric behavior of the Martian surface we have undertaken laboratory electromagnetic characterization in thefrequency range 1 MHz to 3 GHz of the total set of minerals identified by TES Volcanic rocks with a well defined mineralogyand petrology from potential terrestrial analogues sites have also been included in the study Our primary objective is toquantify the range of electrical losses that may be encountered by the various Radar sounding and imaging experimentsdedicated to map the physical properties of the Martian surface and subsurface searching mainly for underground water Theelectromagnetic properties of these Mars-like materials are presented as a function of various geophysical parameters, such

as porosity, bulk density and temperature Using a basaltic Mars-like soil and soil density distribution provided by TES data

We integrated those measurements to form a primary Loss tangent and complex dielectric map of the Martian surface.Author

Mars Surface; Planetary Mapping; Surface Roughness; Density Distribution; Dielectric Properties

20050170010 Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Berlin, Germany

Beyond the Equilibrium Paradigm:Glacial Deposits in the Equatorial Regions of Mars

Helbert, J.; Benkhoff, J.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945Contract(s)/Grant(s): DFG-BE-1630/2; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only aspart of the entire parent document

While Mars has been considered for a long time a dry place except for the early Noachian, this view has changed in recentyears This started mainly after the MOC imagery showed features like the gullies and morphological features which can beassociated with glacial activity Now the motion was discussed that at least small amounts of water or ice had been present

in the recent past on Mars Still, the common notion was that Mars today is a dry place With the excellent dataset of theGamma and Neutron spectrometer (GRS and HEND) on board of Mars Odyssey this view had to be corrected The instrument

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detected water abundance of at least 8wt% in the equatorial regions of Mars and this water is found within the first 2m belowthe surface, the penetration depth of the instrument.

Author

2001 Mars Odyssey; Equatorial Regions; Mars Surface; Morphology; Penetration; Water

20050170012 Cologne Univ., Germany

3-Dimensional Chemical Analyses of Components in the Carbonaceous Chondrites Acfer 209 (CR) and Allende (CV)

Hezel, D C.; Palme, H.; Burkhardt, C.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also20050169945; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI

Components of meteorites are 3-dimensional objects, which are usually studied in 2- dimensional thin sections Oneexception are recent tomographic X-ray studies of Allende volumes by [1] This method has the disadvantage of producingonly BSE-like images without detailed chemical information: We have started to obtain 3-dimensional chemical data sets formeteoritic volumes The results are important for a number of reasons: (1) Calculation of accurate chemical bulk compositions

of chondrules and CAIs Such data are relatively rare, but of particular interest for a variety of important questions, such asthe chondrule - matrix complementarity described by [2] A precise knowledge of chondrules compositions is crucial forchondrule forming mechanisms Another question related to bulk chondrule compositions is the identification of chondruleprecursor components and their origin [3]

Derived from text

Carbonaceous Chondrites; Chemical Analysis; Chemical Composition; Chondrule; Meteoritic Composition; Meteorites

Rheological Properties of Late-Stage Lava Flows on Ascraeus Mons: New Evidence from HRSC

Hiesinger, H.; Head, J W., III; Neukum, G., et al.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English;See also 20050169945; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

The Tharsis Montes, Arsia Mons, Pavonis Mons, and Ascraeus Mons, are large volcanic constructs that are part of theTharsis rise The Tharsis rise is commonly interpreted to be the result of a long-lasting large mantle upwelling that constructedthe rise through a combination of uplift and magmatism (plutonism and volcanism) Of particular interest is the construction

of the huge individual edifices, their ages, duration, episodicity, and rheology Here we report on estimates of the rheologicalproperties of late-stage lava flows on the eastern flank of Ascraeus Mons, Mars Additional information is included in theoriginal extended abstract

Author (revised)

Rheology; Mars Volcanoes; Lava; Planetary Geology

20050170016 University of Northern Arizona, Flagstaff, AZ, USA

Martian Central Pit Craters

Hillman, E.; Barlow, N G.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945;Original contains color illustrations

Contract(s)/Grant(s): NAG5-12510; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

of the entire parent document

Impact craters containing central pits are rare on the terrestrial planets but common on icy bodies Mars is the exceptionamong the terrestrial planets, where central pits are seen on crater floors ( floor pits ) as well as on top of central peaks ( summitpits ) Wood et al [1] proposed that degassing of subsurface volatiles during crater formation produced central pits Croft [2]argued instead that central pits might form during the impact of volatile-rich comets Although central pits are seen in impactcraters on icy moons such as Ganymede, they do show some significant differences from their martian counterparts: (a) onlyfloor pits are seen on Ganymede, and (b) central pits begin to occur at crater diameters where the peak ring interiormorphology begins to appear in terrestrial planet craters [3] A study of craters containing central pits was conducted byBarlow and Bradley [4] using Viking imagery They found that 28% of craters displaying an interior morphology on Marscontain central pits Diameters of craters containing central pits ranged from 16 to 64 km Barlow and Bradley noted thatsummit pit craters tended to be smaller than craters containing floor pits They also noted a correlation of central pit craterswith the proposed rings of large impact basins They argued that basin ring formation fractured the martian crust and allowedsubsurface volatiles to concentrate in these locations They favored the model that degassing of the substrate during crater

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formation was responsible for central pit formation due to the preferential location of central pit craters along these basin rings.Derived from text

Mars Craters; Planetary Crusts; Planetary Geology; Structural Basins; Cratering; Mars Surface

20050170017 NASA Ames Research Center, Moffett Field, CA, USA, Virginia Univ., Charlottesville, VA, USA

A Sedimentary Platform in Margaritifer Sinus, Meridiani Terra, and Arabia?

Howard, A D.; Moore, J M.; Irwin, R P., III; Craddock, R A.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.;

In English; See also 20050169945; Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

The Margaritifer-Meridiani-Arabia highlands-lowlands (H-L) transition has long been recognized as the most fluviallydissected region of Mars However, the geomorphic evolution of this region remains enigmatic, particularly the origin of thelayered deposits of Meridiani Terra and Arabia We suggest that a portion of this regional slope served as a fluvial depositionalplatform during the late Noachian

Derived from text

Geomorphology; Mars Surface; Geochronology; Sediments

20050170018 NASA Johnson Space Center, Houston, TX, USA, National High Magnetic Field Lab., Tallahassee, FL, USA

A Model for Siderophile Element Distribution in Planetary Differentiation

Humayun, M.; Rushmer, T.; Rankenburg, K.; Brandon, A D.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.;

In English; See also 20050169945; Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

Planetary differentiation begins with partial melting of small planetesimals At low degrees of partial melting, a sulfur-richliquid segregates by physical mechanisms including deformation-assisted porous flow Experimental studies of the physicalmechanisms by which Fe-S melts segregate from the silicate matrix of a molten H chondrite are part of a companion paper.Geochemical studies of these experimental products revealed that metallic liquids were in equilibrium with residual metal inthe H chondrite matrix This contribution explores the geochemical signatures produced by early stages of core formation.Particularly, low-degree partial melt segregation of Fe-S liquids leaves residual metal in the silicate matrix Some achondritesappear to be residues of partial melting, e.g., ureilites, which are known to contain metal The metal in these achondrites mayshow a distinct elemental signature To quantify the effect of sulfur on siderophile element contents of residual metal we havedeveloped a model based on recent parametrizations of equilibrium solid metal-liquid metal partitioning experiments.Derived from text

Protoplanets; Siderophile Elements; Models; Geochemistry

20050170019 State Univ of New York, Stony Brook, NY, USA

Experimental Basalt Alteration at Low-pH: Implications for Weathering Relationships on Mars

Hurowitz, J A.; Tosca, N J.; McLennan, S M.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; Seealso 20050169945; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

The chemistry of sedimentary rocks has long been utilized for the reconstruction of climatic, geographic and tectonicconditions in the Earth’s past Naturally, the chemical and mineralogical changes that accompany weathering of the Earth’sgranodioritic upper crust have been studied in great detail to better understand processes controlling the composition ofsedimentary rocks Weathering of basaltic rocks has been studied as well, and there is a reasonable understanding of the bulkchemical and mineralogical changes that accompany alteration of such rocks under terrestrial conditions In contrast, Martiansoils and altered rocks, which undoubtedly reflect the end product of some combination of physical and/or chemical alteration,

do not appear to have evolved in a manner consistent with alteration of basalts as we know it on Earth Here we present newinsights into weathering processes on Mars utilizing the results of alteration experiments performed at low pH on syntheticbasalts of Martian composition

Derived from text

Basalt; Mineralogy; Planetary Geology; pH; Weathering; Mars Surface; Chemical Composition; Sedimentary Rocks

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20050170021 Idaho State Univ., Pocatello, ID, USA

Petrologic Evidence for Multiple, Chemically Evolved Magma Batches and Implications for Plains Volcanism on Earth and Mars

Hughes, S S.; Sakimoto, S E H.; Gregg, T K P.; Brady, S M.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.;

In English; See also 20050169945; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01,Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Small mafic shield volcanoes, abundant on the terrestrial planets, are the dominant landform in provinces characterized

by plains-style volcanism Exemplified on Earth within both oceanic and continental settings (e.g., Hawaii, Snake RiverPlains), they provide analogs for similar systems on other planets, especially Mars Topographic analysis of individualQuaternary mafic shields on the eastern Snake River Plains (ESRP) of Idaho (the type area for plains-style volcanismdemonstrates similarity in size, volume, and shape of these shields, as well as the vent spacing in the volcanic fields, with those

of the Tempe Terra and Syria Planum regions of Mars Geochemical and physical volcanologic studies of the ESRP show anemerging model of volcanic evolution that implies multiple small batches of magma derived from upper mantle sources.Various chemical trends are illustrated, exemplified by La vs MgO, that argue for a system with variably evolved magmabatches and possibly several magmatic sources Petrologic modeling suggests that early magmas in the sequence form(layered?) sub-volcanic mafic intrusions that fractionate to evolved compositions Later mafic magmas commingle with theseearlier-derived intrusions, partially melt and assimilate late-stage fractionates, and erupt with chemically evolved, butisotopically un-evolved compositions

Derived from text

Mars Volcanoes; Earth Surface; Petrology; Magma; Plains; Geochemistry; Mineralogy

20050170023 Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Berlin, Germany

MERTIS: A Thermal Infrared Imaging Spectrometer for the Bepi-Colombo Mission

Helbert, J.; Jessberger, E.; Benkhoff, J.; Arnold, G.; Banaszkiewicz, M.; Bischoff, A.; Blecka, M.; Calcutt, S.; Colangeli, L.,

et al.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Among the terrestrial planets, Mercury plays a special role It is the smallest planet, the densest, the one with the probablyoldest surface heavily gardened by space weathering, and shows large daily surface temperature variations UnderstandingMercury is crucial to develop a better understanding of the early processes in the inner solar system, of how our Earth formed,how it evolved, and how it interacts with the Sun The ESA mission Bepi-Colombo consists of two probes - a planetary and

a magnetospheric orbiter The mission will be launched in 2012 and will reach Mercury in 2016 MERTIS is part of thepayload of the planetary orbiter, focused on understanding the surface and interior of Mercury

Author

Mercury Surface; Imaging Spectrometers; Thermal Mapping; Surface Temperature

20050170024 Institute of Space and Astronautical Science, Sagamihara, Japan

Formation Process of Lunar Sinuous Rilles by Thermal Erosion of Basaltic Lava Flow

Honda, Chikatoshi; Fujimura, Akio; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also20050169945; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parentdocument

One of the major negative relief features on the terrestrial planets and satellites are sinuous rilles, which origin has beenstill debated They possess conspicuous morphological characteristics of meandering channels or valleys, which is decreasing

of depth and width Normal rilles are straight or gently curved and considered to be graben-type faults Crater chains insometimes form irregular fractures like a rille, but they are excluded from the definition of sinuous rille Lunar sinuous rillesare occasionally found in the maria and mare-highland boundaries, and most of them are concentrated around the MareImbrium and in the Oceanus Procellarum According to, lunar sinuous rilles have typical dimensions of 30 - 40 km length and

of less than 1 km width The origin of these features differs on each planet or satellite; hence, we investigated the origin ofthe lunar sinuous rille due to existence of information for consideration of the origin (e.g., chemical composition of rock andelevation of rim and floor of sinuous rille)

Derived from text

Lunar Maria; Lunar Topography; Basalt; Lava; Fluid Flow

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20050170026 Maryland Univ., College Park, MD, USA

Re-187 Os-187 Isotopic and Highly Siderophile Element Systematics of Group IVB Irons

Honesto, J.; McDonough, W F.; Walker, R J.; McCoy, T J.; Ash, R D.; Lunar and Planetary Science XXXVI, Part 8; [2005];

2 pp.; In English; See also 20050169945; Original contains color illustrations

Contract(s)/Grant(s): NNG04GG17G; NNG04GK52G; NAG5-13464; Copyright; Avail: CASI; A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

Study of the magmatic iron meteorite groups permits constraints to be placed on the chemical and isotopic composition

of parent bodies, and the timing of, and crystal-liquid fractionation processes involved in the crystallization of asteroidal cores.Here we examine Re-Os isotopic and trace elemental systematics of group IVB irons Compared to most irons, the ironscomprising this group are enriched in some of the most refractory siderophile elements, yet highly-depleted in most volatilesiderophile elements These characteristics have been attributed to processes such as high temperature condensation ofprecursor materials and oxidation in the parent body Most recently it has been suggested that both processes may be involved

in the chemical complexity of the group Here, high precision isotopic and highly siderophile element (HSE) concentrationsare used to further examine these possible origins, and the crystallization history of the group In addition, we have begun toassess the possibility of relating certain ungrouped irons with major groups via multi-element, trace element modeling In acompanion abstract, the isotopic and trace element systematics of the ungrouped iron Tishomingo are compared with the IVBirons

Author

Iron Meteorites; Magnetic Materials; Crystallization; Asteroids; Rhenium Isotopes; Osmium Isotopes

20050170027 California Univ., Los Angeles, CA, USA

MET01210: Another Lunar Mare Meteorite (Regolith Breccia) with Extensive Pyroxene Exsolution, and Not Part of the YQ Launch Pair

Huber, Heinz; Warren, Paul H.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also20050169945; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

MET01210 has been classified as a lunar anorthositic breccia Actually, it is a regolith breccia that contains more marebasalt than highland matter The bulk Al2O3 content (microprobe fused-bead analysis in excellent agreement with analyses

of the fusion crust) is 16.7 wt%, and the lithic and mineral clast components in thin section appear to be of mainly mare origin.From pyroxene mg vs Ti/(Cr+Ti) zonation trends, the dominant mare component probably was a basalt (or diabase) withapprox 2.2 wt% TiO2 A highland component is definitely present, however There are small aphanitic anorthositic impactmelt clasts, and four of the five regolith spheroids identified to date are highly aluminous (24-35 wt% Al2O3) One of these,only 16 m in diameter, is of HASP composition, with 35 wt% Al2O3 and just 34 wt% SiO2 (Kempa and Papike looked forand did not find a relationship between spheroid size and frequency of HASP; our observations, most notably for lunaiteQUE93069, consistently find HASP most abundant among the smallest highland spheroids and of course surface area/volumerelationships should favor HASP development in relatively small objects.) The only mare or mainly mare spheroid is notablyhigh in TiO2, 4.6 wt%, particularly considering that the Al2O3/FeO wt ratio is 1.51, implying that the high-Ti marecomponent has been heavily diluted with highland matter Additional information is included in the original extended abstract.Author (revised)

Meteorite Parent Bodies; Lunar Rocks; Lunar Maria; Meteoritic Composition

20050170028 State Univ of New York, Stony Brook, NY, USA

Mechanically Produced Radical Species at Silicate Surfaces and the Oxidant in Martian Soils

Hurowitz, J A.; Tosca, N J.; McLennan, S M.; Schoonen, M A A.; Lunar and Planetary Science XXXVI, Part 8; [2005];

2 pp.; In English; See also 20050169945; Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

The Labeled Release (LR) and Gas Exchange (GEx) experiments onboard the Viking Landers determined that the Martiansoils at Chryse and Utopia Planitia contain unknown inorganic species of a highly oxidizing nature The LR experimentdemonstrated that the addition of a radioactive (14)C labeled nutrient solution to soil samples resulted in the production of(14)C labeled CO2 due to the breakdown of the organic species introduced In the GEx experiments, humidification of a 1

cu cm Martian soil sample resulted in the production of as much as 790 nanomoles of O2 gas The presence of a highlyoxidizing species in the fine, wind-blown soils on Mars has obvious implications for both the stability of organic species inthe Martian near-surface environment, as well as health implications for future human explorers who may be exposed toreactive dust particles through inhalation At present, the nature of the oxidant in the Martian soils remains enigmatic

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Explanations for their reactivity have called on both exotic chemical compounds and/or unusual formation processes toproduce oxidants In the medical literature, specifically that related to silicosis and the toxicity of mineral dusts, it has longbeen known that the surfaces of freshly ground quartz particles are characterized by highly reactive radical species generated

by the rupture of bonds during the grinding process These surface radical species are stable in dry environments (e.g theMartian surface) and are capable of producing H2O2 and other Reactive Oxygen Species (ROS) in solution Here, we extendthe study of the reactivity of freshly ground mineral surfaces to include the silicate minerals most commonly encountered inbasalts and soils at the Martian surface: feldspar, clinopyroxene and olivine We propose that the oxidizing nature of theMartian soils can be explained by the presence of such mineral surface radical species and propose mechanisms by which theymight be formed under ambient conditions at the Martian surface Additional information is included in the original extendedabstract

Author (revised)

Mars Environment; Planetary Composition; Toxicity; Oxidizers; Silicates; Radicals

20050170029 Arizona Univ., Tucson, AZ, USA

Are Martian Crustal Magnetic Anomalies and Valley Networks Concentrated at Low Paleolatitudes?

Hood, Lon L.; Harrison, Keith P.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also20050169945; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

A broad spatial correlation between the Mars crustal magnetic field and the distribution of valley networks has previouslybeen reported Several possible explanations involving magmatic intrusions, hydrothermal alteration of the adjacent crust, andsurface discharge of water have been suggested In this paper, we investigate whether the distributions of both magneticanomalies and valley networks may have been preferentially concentrated at low paleolatitudes Such a concentration would

be expected if melting of water ice and snow was a stronger source of surface valley erosion in the tropics and if hydrothermalalteration of crustal rocks played an important role in producing the unusually strong martian magnetic anomalies

Author

Magnetic Anomalies; Mars (Planet); Crusts; Intrusion

20050170031 Colorado Univ., Boulder, CO, USA

The Etched Terrain in Arabia Terra, Mars, is Tilted

Hynek, B M.; Phillips, R J.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945;Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

Light-toned bedrock has been observed at the Mars Exploration Rover (MER) Opportunity landing site These outcropsare rich in a slew of mineral and textural signatures that suggest likely formation within water, including probable evaporites.Further, remote sensing data suggest that these outcrops are not a local phenomenon, rather, they are exposed across the entirehematite-bearing plain and well beyond (over an area \g 3 x 10(exp 5) sq km spanning 20 deg of longitude) Recent resultsfrom the OMEGA instrument on Mars Express show that the etched terrain mapped is rich in sulfates, thus corroborating thehypothesis that outcrops 100s to \g1000 km from Opportunity are diagenetically related Moreover, there are potentiallycorrelative terrains (with similar morphologic, thermal, and mineralogic expressions) up to 5,000 km away; including depositswithin the Valles Marineris, Aram Chaos, and isolated exposures across NW Arabia Terra We are still trying to understandthe full extent of these deposits but it is becoming increasingly clear that copious amounts of water acted over an enormousregion of Mars Little is known about the timing of the putative sea and diagenesis of the layers Because of its sedimentaryand apparent subaqueous origin, the etched terrain was likely emplaced as horizontal to sub-horizontal strata In this study wetest for horizontality of the etched terrain layers and interpret the results in terms of the geological history of this region ofMars Additional information is included in the original extended abstract

Author (revised)

Mars Surface; Bedrock; Erosion; Floods; Terrain; Planetary Geology; Etching; Weathering

Lunar and Planetary Science XXXVI, Part II

[2005]; ISSN 1540-7848; In English; Lunar and Planetary Science XXXVI, 14-18 Mar 2005, Houston, TX, USA; See also

20050170552 - 20050170639

Contract(s)/Grant(s): NCC5-679

Report No.(s): LPI-Contrib-1234-Pt-11; Copyright; Avail: CASI;C01, CD-ROM

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Some topics covered: Implications of internal fragmentation on the structure of comets; Atmospheric excitation of marspolar motion; Dunite viscosity dependence on oxygen fugacity; Cross profile and volume analysis of bahram valles on mars;Calculations of the fluxes of 10-250 kV lunar leakage gamma rays; Alluvian fans on mars; Investigating the sources of theapollo 14 high-Al mare basalts; Relationship of coronae, regional plains and rift zones on venus; and Chemical differentiationand internal structure of europa and callisto.

Derived from text

Atmospheric Circulation; Chemical Composition; Comets; Mars Surface; Lunar Rays; Gamma Rays; Basalt

The Core of the Moon - Molten or Solid?

Khan, A.; Mosegaard, K.; Williams, J G.; Lognonne, P.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; InEnglish; See also 20050170551; Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available fromCASI on CD-ROM only as part of the entire parent document

While several studies beginning in the Apollo era and continuing up to the present have tried to detect the lunar core,either geochemically, geophysically or geologically [e.g 1, 2, 3, 4], it has so far proven somewhat elusive The unambiguousdetection of the lunar core is of prime importance as it holds the potential of distinguishing between the various theories forthe formation of the Moon The theory which currently enjoys the greatest success is the giant impact model, which has theMoon forming about 4.5 Gyr ago from the debris produced when a Mars sized proto planet collided with the proto Earth [e.g

5, 6] Simulations reveal that the material from which the Moon is made up contains very little iron and consequently a lunarcore, if it exists, should be small

Derived from text

Lunar Core; Moon; Iron

20050170555 Notre Dame Univ., IN, USA

Petrology of Nakhlite MIL 03346

Kinman, W s.; Neal, C R.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

The new Nakhlite meteorite MIL- 03346 was found in Antarctica at the Miller Range of the Transantarctic Mountainduring the 2003-2004 field season The exterior is approximately 60% covered by a black, wrinkled fusion crust We wereallocated two samples from the 712.5g sample - a 2g whole rock sample and thin section MIL03346,9 Unfortunately, thesamples were received only 8 days before the abstract deadline so only a brief report comprised of mineralogical (electronmicroprobe) data is reported here The major and trace element data, including platinum-group element abundances, will bereported at the conference

Author

Nakhlites; Meteorites; Trace Elements

20050170556 Waseda Univ., Tokyo, Japan

Global Mapping of Elemental Abundance on Lunar Surface by SELENE Gamma-Ray Spectrometer

Kobayashi, M.-N.; Berezhnoy, A A.; DUston, C.; Fujii, M.; Hasebe, N.; Hiroishi, T.; Kaneko, H.; Miyachi, T.; Mori, K.;Maurice, S., et al.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of theentire parent document

Elemental composition on the surface of a planet is very important information for solving the origin and the evolution

of the planet and also very necessary for understanding the origin and the evolution of solar system Planetary gamma-rayspectroscopy is extremely powerful approach for the elemental composition measurement Gamma-ray spectrometer (GRS)will be on board SELENE, advanced lunar polar orbiter, and employ a large-volume Ge detector of 252cc as the main detector[1] SELENE GRS is, therefore, approximately twice more sensitivity than Lunar Prospector GRS, four times more sensitivethan APOLLO GRS The high sensitivity of SELENE GRS will enable us to map element abundances of O, Mg, Fe, Al, Si,

Ti, K, Ca, Th, and U, with lower detection limit than the past missions The Japanese lunar polar orbiter SELENE is scheduledfor launch in 2007 and the GRS will observe the whole area of the moon including the polar region Orbiting the GRS at 100

km in a nominal operation for one year will provide the global mapping of the chemical composition of lunar surface materialfor more elements than Lunar Prospector did [2] Now, the flight model of SELENE GRS was built and will be qualified by

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several environment test Fig 1 shows the schematic drawing It shows an energy resolution of 3 keV @ 1.33 MeV in the GRSsystem In this study, we will exhibit expected performance of SELENE GRS in lunar orbits predicted by preliminary MonteCarlo simulation results and describe scientific topics achievable by SELENE GRS.

Derived from text

Mapping; Gamma Ray Spectrometers; Lunar Maps; Lunar Surface; Planetary Surfaces; Abundance

20050170557 Oulu Univ., Finland

Mars Express HRSC Analysis of Two Impact Craters in Terra Tyrrhena, Mars

Korteniemi, J.; Kostama, V.-P.; Aittola, M.; Ohman, T.; Tormanen, T.; Lahtela, H.; Raitala, J.; Neukum, G.; Lunar andPlanetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentThe surface of Mars is governed by division to smooth northern lowlands and intensely cratered highland terrain in thesouth The cratering record indicates the age of the surface [e.g 1,2], while individual craters original morphology hints tothe target material at the time of impact [3] Additionally, the craters provide natural sinks for later deposited materials, thusshowing glimpses of the evolution of the region they reside in In all, craters provide information on the local and arealevolution phases and processes

Derived from text

Cratering; Mars Craters; Morphology; Mars Surface; Terrain

20050170558 Academy of Sciences (USSR), Moscow, USSR

The Martian North Polar Cap Spirals are the Traces of an Ancient Ice Sheet Collapse

Kostrikov, A A.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROMonly as part of the entire parent document

The surface of north polar cap of Mars is essentially heterogeneous unlike flat terrestrial ice sheets [1] Troughs up to onekilometer deep with gently (no more 10-15 ) sloping are seen all over the ice cap The unique feature of the trough system

is its helical appearance (Fig 1) Analogs of ice spiral structures are not known The troughs have been attributed to the action

of aeolian erosion [2-3], sublimation [4] or to ‘accublation’ hypothesis (glacial flow + sublimation + accumulation) [5-7] It

is supposed that an ice mass transfer occurs by sublimation from equatorward-facing slopes and subsequent accumulation onpole-facing slopes No ideas on origin of spiral pattern have been moved forward with the exception of an attempt to explaintrough revolving by combined effects of accublation and ice movement [8]

Derived from text

Collapse; Ice; Glaciers; Polar Caps; Mars Surface

20050170560 Russian Academy of Natural Sciences, Moscow, Russia

Wind-related Erosion Depressions Within a Small Impact Craters in Chryse and Elysium Planitiae on Mars

Kuznetsov, I V.; Kuzmin, R O.; Greeley, R.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; Seealso 20050170551; Original contains color and black and white illustrations; Copyright; Avail: CASI; A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

High resolution Mars Orbiter Camera (MOC) images [1] show wide variety of the aeolian features within the impactcraters attributed to wind erosion and deposition: different types of bright and dark crater streaks, duneforms, bright transversedunes, interacrater deposits, and rim scouring forms The orientation of these aeolian features is consistent with the direction

of current strong winds [2,3], while origin of some of them could be related with paleowind regime[4] Here we present theresults of study of unknown before phenomenon of the wind-related modification of the impact craters on Mars in the form

of blowout hollows which have been found only in two places on Mars: much more in southern part of Chryse Planitia (CP)and less in south-western part of Elysium Planitia (EP)

Derived from text

Dunes; Mars Craters; Wind Erosion; Wind (Meteorology); Mars Surface

20050170561 Belgian Royal Observatory, Brussels, Belgium

Atmospheric Excitation of Mars Polar Motion

Karatekin, O.; Dehant, V.; deViron, O.; VanHoolst, T.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 1 pp.; InEnglish; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part ofthe entire parent document

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The rotation of Mars is not constant and present irregularities with time Those are mostly associated with the seasonalcycle of Mars’ atmosphere, and the condensation/sublimation of the icecaps The dynamics of Mars atmosphere shows a largeannual and semi-annual signal, in addition to the diurnal cycle Besides those periodic components, in the present study weinvestigate the other atmospheric effects that can excite the polar motion The influence of surface/atmosphere interactions onthe rotation dynamics is classically estimated using the angular momentum approach The Mars-atmosphere system isconsidered as isolated, so that any change in the atmosphere angular momentum is associated with an opposite change in theplanetary angular momentum The angular momentum of the atmosphere can be separated into two parts: a matter termrepresenting the rigid rotation of the fluid layer with the planet, and a wind term accounting for the relative motion of the fluidwith respect to the surface of the planet.

Derived from text

Rotation; Mars Atmosphere; Planetary Surfaces; Atmospheric Circulation; Excitation; Surface Reactions

20050170563 Academy of Sciences (Russia), Moscow, Russia

The Smerdyacheye Lake: New Evidence for Impact Origin and Formation Age

Kashkarov, L L.; Badijukov, D D.; Ivliev, A I.; Kalinina, G V.; Nazarov, M A.; Lunar and Planetary Science XXXVI, Part11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations; Copyright; Avail: CASI;A01,Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

The Smerdyacheye Lake of about 350 m in diameter is located in the Moscow district approximately 140 km east ofMoscow This lake has a circular shape and a well-developed rim Based on the features, it has been suggested that the lake

is a possible meteorite crater The suggestion was confirmed by a fragment of a possible impactite found in the rim In thispaper we report on a glass bead discovered recently in the vicinity of the lake In composition and texture the glass is similar

to impact-glasses and supports strongly impact origin of the lake First data on fision track age and TL characteristics of thisglass bead are reported

Author

Meteorite Craters; Age Factor; Beads; Glass; Lakes

20050170564 Idaho Univ., Moscow, ID, USA

Compressive Anti-Cracks at the Tips of Strike-Slip Faults on Europa and Implications for Fault Mechanics

Kattenhorn, Simon A.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROMonly as part of the entire parent document

Secondary fractures, or tail-cracks, at the tips of strike-slip faults are common on Europa and form in response tohigh-magnitude tensile stresses induced by fault slip However, linear elastic fracture mechanics theory (LEFM) predicts bothextensional and compressive quadrants around fault tips Theoretically, these quadrants can be associated with tensilesecondary fracturing (cracks) and compressive secondary fracturing (anti-cracks), respectively The existence of such features

in terrestrial rocks has been widely documented

Derived from text

Fracture Mechanics; Geological Faults; Europa; Cracks

20050170567 University of Western Ontario, London, Ontario, Canada

Comparison of Predicted Salt Precipitation Sequences with Mars Exploration Rover Data

King, P L.; Lescinsky, D T.; Nesbitt, H W.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; Seealso 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

We compare predicted salt sequences for Mars with Mars Exploration Rover (MER) data to place constraints on martianwaters On Mars, geomorphic and geochronologic evidence suggest that surface solutions occurred episodically, and chemicalevidence suggests limited weathering of the basaltic crust Saline solutions are produced via leaching of bulk martian surfacematerials (martian and impactor materials) containing sulfides, olivine, pyroxene, plagioclase glass The resulting bulksolution would contain Mg-Ca-Na-(K-Fe)-C-O-H-S-(N-P)- halogen species, with abundant Mg, Na, SO4 and Cl Localcompositional variations are likely On Mars, sulfate stays in solution, unlike on Earth where sulfate is reduced to sulfide eithervia biologic processes or hydrothermally at mid-ocean ridges We model the martian solution compositions as they areconcentrated (via freezing or evaporation) using salt solubility and phase equilibria, assuming: 1) thermodynamic modeling

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is appropriate; 2) 25 C and approx 10(exp 5) Pa phase diagrams are valid at martian conditions; and, 3) activity coefficientsare unity.

Derived from text

Sodium Chlorides; Precipitation (Chemistry); Mars Exploration; Mars Surface; Data Processing

20050170569 Wisconsin Univ., Madison, WI, USA

Correlation Between Aluminum-26 Ages and Bulk Si/Mg Ratios for Chondrules from LL3.0 - 3.1 Chondrites

Kita, N T.; Tomomura, S.; Tachibana, S.; Nagahara, H.; Mostefaoui, S.; Morishita, Y.; Lunar and Planetary Science XXXVI,Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations; Copyright; Avail: CASI;A01,Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Recently, the Al-26 - Mg-26 analyses were performed for many chondrules from least equilibrated chondrites by usingion microprobe The initial Al-26/Al-27 ratios of these chondrules are between 1.5 x 10(exp -5) and 3 x 10(exp -6), 1-3 millionyears (Myr) younger than CAIs with the canonical initial ratios of 5 x 10(exp -5) Similar age differences between CAIs andchondrules are also reported from absolute Pb-Pb ages Thus, the initial Al-26/Al-27 ratio of the solar system is considered

to be homogeneous for applying the Al-26 - Mg-26 chronometer

Derived from text

Aluminum Isotopes; Age Factor; Silicon; Chondrule; Chondrites; Meteoritic Composition; Magnesium Isotopes

20050170570 Muenster Univ., Germany

The Hf-W Age of the Lunar Magma Ocean

Kleine, T.; Mezger, K.; Palme, H.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parentdocument

The early chemical differentiation of the Moon was dominated by the crystallization of a magma ocean Determining thecrystallization age of the lunar magma ocean (LMO) is critical for understanding the timing of Moon formation, melting, andsubsequent differentiation and cooling Currently, the most suitable isotope system for dating the crystallization of the LMO

is the Hf-182 - W-182 decay scheme, because the Hf/W ratios varied significantly between the different LMO reservoirs, and

W isotope variations can have only been produced in the first approx 60 Myr of the solar system Thus, information on earlydifferentiation of the Moon is preserved in the 182W/184W of early-formed lunar reservoirs and is carried by lunar samplesderived from any of these sources A chronological interpretation of W isotope ratios for lunar whole-rocks and minerals,however, has been hampered by the neutron-flux induced production of W-182 from Ta-181 caused by the intense cosmicradiation reaching the surface of the Moon Analyzing the metals of lunar samples can overcome this problem because metals

do not contain significant Ta that could be converted to W-182 We present W isotope data for metals from KREEP-rich and-poor highland breccias and low-Ti and high-Ti mare basalts To investigate the effect of cosmogenic W-182 production inwhole-rock samples, the W isotopes in some whole-rocks have also been analyzed

Author

Hafnium Isotopes; Tungsten Isotopes; Age Factor; Lunar Geology; Magma; Oceans; Crystallization

20050170571 Muenster Univ., Germany

Tungsten Isotopes Provide Evidence that Core Formation in Some Asteroids Predates the Accretion of Chondrite Parent Bodies

Kleine, T.; Mezger, K.; Scherer, E.; Palme, H.; Scherer, E.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; InEnglish; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part ofthe entire parent document

Chondrites are generally assumed to be the most primitive rocks of the solar system and to represent the precursormaterial from which asteroids accreted and then differentiated Chondrites contain CAIs and chondrules, the formerrepresenting the oldest yet dated material formed in the solar system Age differences between CAIs and chondrules based onthe U-Pb and 26Al-26Mg chronometers show that chondrule formation persisted for at least approx 2.5 Myr, indicating thataccretion of chondrite parent asteroids lasted for at least approx 2.5 Myr These results contrast with estimates from planetaryaccretion models that propose that the first planetary objects formed within 1 Myr after condensation of the first solid matter.Hf-182 - W-182 ages for iron meteorites show that differentiation (i.e., core formation) of their parent bodies occurred withinapprox 5 Myr of each other For the first time, we link this differentiation event to the ages of CAIs, chondrules, and chondrite

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parent asteroids, by applying the Hf-182 - W-182 chronometer to CAIs, primitive chondrites, and iron meteorites.

Author

Tungsten Isotopes; Planetary Cores; Asteroids; Chondrites; Meteoritic Composition; Hafnium Isotopes

20050170573 Aizu Univ., Fukuyama, Japan

Shape Modeling for the Asteroid (25143) Itokawa, AMICA of Hayabusa Mission

Kobayashi, S.; Demura, H.; Asada, N.; Furuya, M.; Hashimoto, T.; Saito, J.; Lunar and Planetary Science XXXVI, Part 11;[2005]; 1 pp.; In English; See also 20050170551; Original contains color and black and white illustrations; Copyright; Avail:CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Hayabusa established Earth-swingby a success in May 12, 2004 and the spacecraft is on course to the target asteroidItokawa Hayabusa mission is a sample return program of ISAS/JAXA The spacecraft is going to arrive at Itokawa and totouch down on the surface for sampling materials in autumn of 2005 Our science team requires 3D shape model of theasteroid, which provides fundamental information for making a decision on selecting landing sites Nowadays, image-basedmodeling is the favored method of shape recognition of asteroids For example, Wild 2 was recognized its irregular shape bystereo images We found following problems make it difficult to develop the precise shape model by stereo method; (1)Hayabusa is equipped a single-eyed camera, (2) Hayabusa doesn’t know own exact position enough to ordinary stereo method.Here we report the procedures and results of this modeling with AMICA (Asteroid Multiband Imaging Camera) and attitude

of spacecraft, and distance between target asteroid and the spacecraft only

Derived from text

Three Dimensional Models; Sample Return Missions; Imaging Techniques; Cameras; Asteroid Missions; Shape Optimization

20050170574 Wien Univ., Austria

The 2004 ICDP Bosumtwi Impact Crater, Ghana, West Africa, Drilling Project: A First Report

Koeberl, Christian; Milkereit, B.; Overpeck, J T.; Scholtz, C A.; Peck, J.; King, J.; Lunar and Planetary Science XXXVI, Part11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations

Contract(s)/Grant(s): NSF-ATM-04-02010; ANSF Proj P17120-N10; Copyright; Avail: CASI;A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

The 10.5-km-diameter 1.07 Ma Bosumtwi impact crater was the subject of an interdisciplinary and international drillingeffort of the International Continental Scientific Drilling Program (ICDP) from July to October 2004 Sixteen different coreswere drilled at six locations within the lake, to a maximum depth of 540 m A total of about 2.2 km of core material wasobtained

Author

Geophysics; Ghana; Lunar Craters; Seismology; Drilling

20050170575 International Research School of Planetary Sciences, Pescara, Italy

Morphology and Morphometry of Fluidized Ejecta Blankets: New Results from the Mars Express High Resolution Stereo Camera

Komatsu, G.; Ori, G G.; DiLorenzo, S.; Rossi, A P.; Neukum, G.; Lunar and Planetary Science XXXVI, Part 11; [2005];

2 pp.; In English; See also 20050170551; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Impact craters on Mars often exhibit features that are not observed on the Moon The most unusual is the ejecta blanketmorphology Martian ejecta blankets are in general characterized by a terminal low concentric ridge (rampart) or a flat-toppedplateau (pancake), or radial grooves and scouring This type of ejecta morphology collectively called layered ejecta structures

is in general attributed to various ejecta displacement processes due to involvement of volatiles derived from the subsurface

or of atmosphere We utilized images and stereo-derived topographic data acquired by the HRSC (High Resolution StereoCamera) onboard Mars Express in order to study geology of Martian impact crater ejecta blankets We examined more than

a dozen impact craters with possible evidence for water involvement during the formation by constructing 3-dimensionalviews and deriving various parameters The high precisions of the HRSC data set ensure quantitative analyses of such impactcraters better than previously possible The investigated relatively pristine impact craters are distributed in the eastern Tharsis,but examples from other regions are also included We examined various geomorphology and geomorphic parameters ofMartian layered ejecta structures The layered ejecta structures on Mars have been classified into different types includingsingle lobe, multi lobate and double lobate Representative topographic profiles from our study clearly show a wide range ofmorphology An example of typical single-lobed layered ejecta structure is shown having a thick flat-topped plateau and a

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terminal rampart The double lobate type is characterized by clearly separate inner thick lobes and much thinner outer lobes.Derived from text

Cameras; Ejecta; Geomorphology; High Resolution; Mars Express; Stereophotography; Mars Craters

20050170577 Arizona State Univ., Tempe, AZ, USA

Palagonite-like Alteration Products on the Earth and Mars 2: Secondary Mineralogy of Crystalline Basalts Weathered Under Semi-Arid Conditions

Kraft, M D.; Michalski, J R.; Sharp, T G.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI

The Martian surface may be mineralogically altered from its pristine, igneous state Aqueous alteration on Mars wouldlead to formation of secondary minerals, which could occur in soils, weathering rinds, rock coatings, or sedimentary cements

In order to understand the alteration state of the Martian surface, it is crucial that we anticipate what secondary minerals mighthave formed on Mars It is also critical that we understand how secondary materials affect remote observations In particular,

we must understand spectral observations of secondary minerals in geologic context: How do these materials appear when theyoccur as weathering rinds, soils, cements, or coatings? Small amounts of weathering could produce significant differencesbetween fresh rock and weathered rock spectra Previously, we investigated thermal infrared spectra of silica-coated rocks andshowed that small amounts of amorphous silica coating basalt greatly influenced spectra, with silica coatings thicker than 7-10

m completely obscuring the basalt s thermal infrared spectral signature [1] In weathering rinds, fine-grained, secondarysilicates tend to coat primary minerals, and can be thought of as discontinuous, rock-penetrating coatings Consequently, weexpect thermal infrared spectral effects of weathering rinds to be similar to those seen with silica coatings, in that smallvolumes of secondary products will have large effects

Derived from text

Planetary Geology; Mineralogy; Crystallinity; Basalt; Temperature Effects; Silicon Dioxide

20050170579 Moscow State Univ., Russia

The Gagarin Ring Structure, Russia: A Possible Meteorite Crater

Krivosheya, K V.; Badyukov, G D.; Badjukov, D D.; Raitala, J.; Lunar and Planetary Science XXXVI, Part 11; [2005];

The Gagarin ring structure has been described as a proposed meteorite crater in 1975 The assumption was based onmorphological details of the structure and geophysical data Here we report new data which support the possible impact origin

of the structure

Derived from text

Geophysics; Meteorite Craters; Structural Properties (Geology); Mineralogy; Russian Federation

Chemical Differentiation and Internal Structure of Europa and Callisto

Kuskov, O L.; Kronrod, V A.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color illustrations

Contract(s)/Grant(s): RFBR-03-05-64413; RFBR-04-05-64867; Copyright; Avail: CASI; A01, Hardcopy; Available fromCASI on CD-ROM only as part of the entire parent document

The purpose of this study is to reproduce characteristic features of the internal structure of Europa and Callisto on the basis

of Galileo gravity measurements, geochemical constraints on composition of silicate fraction of ordinary and carbonaceouschondrites, and thermodynamic data on the equations of state of water, high-pressure ices, and meteoritic material.Derived from text

Chemical Composition; Europa; Callisto; Galileo Spacecraft; Geochemistry; Gravitation; Meteoritic Composition

20050170581 Kharkiv State Univ., Kharkiv, Ukraine

Studying the Phase Dependence of Lunar Surface Brightness Using Data of Integral Observations

Korokhin, V V.; Velikodsky, Yu, I.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

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Lane and Irvine carried out the integral photometrical observations of the Moon at Le Houga observatory (South France)

in 1964-1965 These are the most full integral observations of the Moon: the Moon was observed over phase angles 6 degreesless than or equal to alpha less than or equal to 120 degrees in nine narrow bands (350-1000 nm) and in UBV But theirsuitability for studying the phase dependence of brightness of lunar surface decreases through presence of systematical errorscaused by influence of libration variations and changing of contribution of mares and highlands in integral brightness withphase changes Therefore we have tried to correct Lane’s and Irvine’s data

Derived from text

Brightness; Lunar Surface; Photometry; Moon; Data Processing

Siderophile Geochemistry of Ureilites: Reading the Record of Early Stages of Planetesimal Core Formation

Kallemeyn, Gregory W.; Warren, Paul H.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

Ureilites, the second most abundant type of achondrite, formed as partial melt restites (olivine + pyroxene + minor, 0.2-6wt%, carbon) in the mantles of carbonaceous asteroids Degrees of melting were sufficient to virtually eliminate plagioclasefrom the entire ureilite milieu; at temperatures of approx.1210- 1300 C [1] According to some recent interpretations [e.g., 2,3]core formation commences not long after an asteroidal interior reaches the Fe-FeS eutectic (approx.990 C) This scenarioseems implausible for the interior of an asteroid, where extensive mobilization of solid components (without implausibly high

S, only minor proportions of metal will melt near the eutectic) can only be expected as a concomitant of extensive matrixmelting At any rate, at about the same time the ureilites underwent partial melting, they acquired moderate to major depletions

in siderophile elements Natural siderophile variations are notoriously untidy, but collectively the many ureilite samples canpotentially furnish important insight into the early stages of core formation

Derived from text

Ureilites; Protoplanets; Olivine; Geochemistry; Melting; Carbon

20050170585 Oklahoma Univ., Norman, OK, USA

Large Eddy Simulation of Coherent Structures and Dust Devil-like Vortices in the Martian Boundary Layer

Kanak, K M.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROMonly as part of the entire parent document

Dust devils are columnar convective vortices made visible by the presence of dust or other particulates They occur mostoften in environments characterized by low ambient wind speeds and strong unstable lapse rates There is increasing evidencethat vertical vortices in the terrestrial convective boundary layer may occur frequently without the presence of visible tracersand therefore be much more common than previously thought The ubiquity of dust devil tracks in certain regions on Marssuggest that they are a regular feature of the Martian boundary layer The implications of dust devils on vertical transports ofheat, momentum, and particulates may be significant In addition, they could pose some threat to landers and rovers, orspacecraft upon descent and landing This study presents results from an idealized Large Eddy Simulation (LES) of theMartian Boundary Layer (MBL) Comparisons are made with prior Martian dust devil modeling study results, in whichdifferent numerical models were used and with observations

Author

Coherence; Dust; Vortices; Mars Surface; Boundary Layers; Large Eddy Simulation

Analysis of Martian Pyroxene Compositions in Syrtis Major: Full MGM Application to OMEGA

Kanner, L C.; Mustard, J F.; Bibring, J-P.; Gendrin, A.; Langevin, Y.; Gondet, B.; Pelkey, S.; Lunar and Planetary ScienceXXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations; Copyright; Avail:CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Spectra from the OMEGA visible-infrared spectrometer [1] of the Syrtis Major region of Mars are analyzed for pyroxenecomposition and the relationships to local geologic units Individual spectra were analyzed using the Modified Gaussian Model(MGM) [2] Final MGM fits indicate the presence of two pyroxenes in Syrtis Major, in agreement with previous studies [3,

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4] The results indicate that the old cratered terrains are low-calcium pyroxene rich while the overlying volcanic province ishigh-calcium pyroxene rich Olivine is likely present in some regions.

Author

Pyroxenes; Mars Surface; Infrared Spectrometers; Craters

20050170587 Geological Survey, Flagstaff, AZ, USA

Aqueous Chemistry, Physical Chemistry, and Sedimentology of Rocks at the Mars Rover Landing Sites

Kargel, J S.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of theentire parent document

The Mars Exploration Rovers, Opportunity and Spirit, have provided critical ground truth observations pertinent to globaldata sets and observations that have been interpreted in terms of an aqueous past Most crucial from these new rover missionshas been their ability to travel to rock outcroppings and probe the weathered exteriors and fresher interiors of rocks withchemical and mineralogical and a variety of optical imaging systems Both rovers have returned data indicating layer-by-layeraqueous deposition or aqueous alteration under conditions that were almost certainly highly acidic and hypersaline but not ascold as current conditions The two landing sites are very different, but the rover observations dovetail nicely with synopticobservations made from orbiters The accumulated sets of observations for both sites indicate periods of hydrogeologicprocesses involving huge amounts of liquid water Both rovers have produced data consistent with possible continued aqueousprocesses, most likely involving minute traces of acidic, saline brines that are liquid and chemically active in the uppercentimeters on warm days, but frozen much of the time Terrestrial analog sites provide a rich variety of insights into the cause

of the observed chemistry, mineralogy, and physical sedimentology at each rover site A sea or big lake is implicated forMeridiani Planum, and a huge debris flow is likely at Gusev Crater Room remains for alternate or modified interpretations,but water is unavoidable

Author

Mars Surface; Mineralogy; Physical Chemistry; Sedimentary Rocks

20050170588 Museum of Natural History, London, UK

Interpreting Micrometeoroid Residues on Metallic Spacecraft Surfaces: Clues from Low Earth Orbit, the Laboratory and to Come from Stardust?

Kearsley, A T.; Burchell, M J.; Graham, G A.; Cole, M J.; Wallis, D.; Lunar and Planetary Science XXXVI, Part 11; [2005];

Surfaces of spacecraft returned from low Earth orbit (LEO) preserve a record of high velocity collisions with small (lessthan 1mm) particles Surveys of features on metal, glass and other materials have identified remains of micrometeoroids.Analytical electron microscopy using energy dispersive X-ray spectrometry (EDS) has proven very successful in distinction

of impacts by artificial and natural particles, and holds promise for interpretation of micrometeoroid residues in terms ofparticle origin

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Micrometeoroids; Residues; Metallic Glasses; Surface Layers; Spacecraft Shielding

20050170589 NASA Johnson Space Center, Houston, TX, USA

In-Situ Heating Decrease Kinetics of Aliphatic Hydrocarbons in Tagish Lake Meteorite by Micro-FTIR

Kebukawa, Y.; Nakashima, S.; Zolensky, M E.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; Seealso 20050170551; Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

Carbonaceous chondrites are known to contain up to 3wt.% C, the major part of which corresponds to a macromolecularorganic fraction Chondritic organic matter is based on small aromatic units, cross-linked by short aliphatic chains rather thanlarge clusters of polyaromatic structures Two main characteristic features of those organics measured by FTIR are: (1) anequivalent intensity of the asymmetric stretching mode absorptions for CH3 (2960/cm) and CH2 (2920/cm) and (2) a lack ofaromatic CH-stretching mode (3040/cm) Tagish Lake is a new type of water- and carbon-rich type 2 carbonaceous chondrite.Its total carbon content is approx 5 wt%, of which the organic carbon content reaches approx 1.3 wt% Tagish Lake may havenever experienced temperatures higher than 120 C after formation of organics based on the disappearance of infrared (IR)organic peaks in step heating experiments Here we report in-situ kinetic heating experiments of organics in Tagish Lake by

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micro-FTIR to characterize the nature of aliphatic hydrocarbons and their thermal stabilities.

Author

In Situ Measurement; Kinetic Heating; Aliphatic Hydrocarbons; Lakes; Meteorites

20050170590 Minnesota Univ., Minneapolis, MN, USA

Dunite Viscosity Dependence on Oxygen Fugacity

Keefner, J W.; Mackwell, S J.; Kohlstedt, D L.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English;See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

A detailed understanding of the behavior of dunite flow is crucial because small errors in a laboratory-derived constitutiveequation become large errors when extrapolated to mantle conditions The oxidation state of the upper mantle of the Earth,Mars, and Venus may play a role in the development of endogenic processes that lead to observable surface features Oxygenfugacity is known to have an effect on the viscosity of olivine single crystals under constant stress However, the behavior ofpolycrystalline olivine samples deformed under different oxidation states is less well understood Deformation experimentswere performed on Aheim dunite over ranges of temperature, stress, and solid state buffer to investigate the dependence ofviscosity on oxygen fugacity In many studies of kinetic properties on olivine single crystals and polycrystalline aggregates,oxygen fugacity was buffered at the iron-wustite (IW) buffer by the sample jacket In the present study, we explicitly comparethe strength of samples deformed at the nickel-nickel oxide (NNO) and the iron-wustite solid state buffers in order to quantifythe dependence of creep rate on oxygen fugacity

Author

Dunite; Viscosity; Oxygen; Planetary Mantles

20050170592 NASA Goddard Space Flight Center, Greenbelt, MD, USA

Pickup Ion Mass Spectrometry for Surface Bounded Exospheres and Composition Mapping of Lunar and Planetary Surfaces

Keller, J W.; Zurbuchen, T H.; Baragiola, R A.; Cassidy, T A.; Chornay, D J.; Collier, M R.; Hartle, R E.; Johnson, R E.;Killen, R M.; Koehn, P., et al.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy; Availablefrom CASI on CD-ROM only as part of the entire parent document

Many of the small to medium sized objects in the solar system can be characterized as having surface boundedexospheres, or atmospheres so tenuous that scale lengths for inter-particle collisions are much larger than the dimensions ofthe objects The atmospheres of these objects are the product of their surfaces, both the surface composition and theinteractions that occur on them and also their interiors when gases escape from there Thus by studying surface boundedexospheres it is possible to develop insight into the composition and processes that are taking place on the surface and interiors

of these objects The Moon and Mercury are two examples of planetary bodies with surface bounded exospheres that havebeen studied through spectroscopic observations of sodium, potassium, and, on the moon, mass spectrometric measurements

of lunar gases such as argon and helium

Derived from text

Planetary Surfaces; Lunar Surface; Mass Spectroscopy; Ions; Exosphere; Mapping; Surface Layers; Gas Analysis

20050170594 University of Southern Georgia, Statesboro, GA, USA

Analysis of the Statesboro, Georgia Shock-darkened L5 Chondrite

Kelley, Michael S.; Asher, Pranoti M.; Welten, Kees C.; Jull, A J TImothy; Schultz, Ludolf; Roden, Michael; Mertzman,Stanley A.; Albin, Ed F.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

In August 2003, Statesboro, Georgia farmer Harold Cannon brought an unusual rock to the Department of Geology andGeography at Georgia Southern University There are few naturally occurring rocks on the coastal plain of Georgia, so bydefinition, any rock found there is ‘unusual’ However, this particular specimen turned out to be not only unusual, butotherworldly In mid-June, 2000 Cannon was harvesting a crop of butter beans when his mechanical bean picker pulled therock up from his field In the process, yellow paint from the device was deposited on the specimen Cannon removed the rockand tossed it between a pair of produce freezers under a shed in his back yard For more than 3 years the rock sat exposed

to the elements When Cannon was cleaning the area around the shed in summer 2003, he finally decided to find out exactly

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what the rock was He said he suspected it might be a meteorite because it was heavier than expected for its size, and afterbreaking off a small fragment, he noticed it was very dark inside.

Derived from text

Chondrites; Meteorites

20050170595 Museum fuer Naturkunde, Berlin, Germany

Thin-Skin Delamination of Target Rocks Around the Ries Crater: The Effect of Spallation and Ejecta Drag

Kenkmann, T.; Ivanov, B A.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

The Ries crater is the best suited large impact crater on Earth to study processes of excavation and near-surfacedeformation of target rocks as the amount of erosion is minor We have analysed the deformation of parautochthonous andautochthonous target rocks inside and outside the tectonic crater rim at a distance ranging from 10 to 20 km with respect tothe crater center We have observed several sub-horizontal shear planes (detachments) in stratified target rocks and measuredtheir displacement vector It is suggested that spallation and dragging of the ejecta curtain caused the formation of detachments

in the surrounding of the transient crater cavity A numerical model is compared with the structural data and gives further hints

to the time sequence, applied stresses, and magnitude of shear movements

Derived from text

Craters; Deformation; Displacement; Tectonics; Delaminating

Dual Balloon Concept for Lifting Payloads from the Surface of Venus

Kerzhanovich, Viktor V.; Yavrouian, A H.; Hall, J L.; Cutts, J A.; Lunar and Planetary Science XXXVI, Part 11; [2005];

Introduction: Two high-rated Venus mission concepts proposed in the National Science Foundation Decadal Surveyrequire a balloon to lift payloads from Venusian surface to high altitudes: Venus Surface Sample Return (VESSR) and VenusIn-Situ Explorer (VISE) In case of VESSR the payload is a canister with the surface sample plus a Venus ascent vehicle(VAV), which is a rocket that takes the sample into orbit for rendezvous with an Earth return vehicle VISE is envisioned as

a more limited precursor mission where the surface sample is only taken to high altitudes so that non time-critical analysescan be performed From the balloon point of view, the only difference between these two missions is that the VESSR payload

to be lifted is very much larger than VISE because of the inclusion of the VAV A key problem is that at the time the decadalsurvey was published, no high temperature balloon technology existed to implement either mission Prior technologydevelopment efforts had concentrated on a single balloon that could operate across the entire 0-60 km altitude range, toleratingboth the sulfuric acid aerosols and the extreme temperatures of -10 to +460 C However, this problem was unsolved because

no combination of sufficiently lightweight balloon material and manufacturing (seaming) technology was ever found totolerate the high temperatures at the surface

Author

Balloons; Venus Surface; Orbital Rendezvous; Sample Return Missions; Payloads

Some Simple Models for Rootless Cone Formation on Mars

Keszthelyi, L.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of theentire parent document

Volcanism provides a unique tool to sound for water in Mars geologic past The interaction between molten lava andsurface and ground water produces a range of morphologic features on Earth Many of these features are interpreted to exist

on Mars Rootless cones (a.k.a pseudocraters) have been reported in a number of locations on Mars and interpreted to be theresult of explosive interaction between the liquid lava and groundwater/ice The enigmatic ring structures seen in AthabascaValles may have formed by relatively gentle lava-groundwater interaction Mesas-like features in several areas of Mars areinterpreted as constructional features formed by lava erupted under ice and/or water However, rootless cones remain thefeature most often and definitively cited as evidence of lava-water interaction on Mars Despite the repeated use of theserootless cones to infer the presence of water in the shallow subsurface, only limited quantitative information has been extracted

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from them The minimum depth to subsurface water or ice has been calculated based on the simple assumption that the lavamust conductively heat the substrate, melt ice, and boil water Greeley and Fagents also calculate the amount of gas needed

to propel clasts to build a rootless cone on Earth and Mars They concluded that only small amounts of water are necessaryfor rootless cones to form on Mars Simple Steam Accumulation Model: In rootless

Author

Ground Water; Lava; Mars Craters; Planetary Geology; Ring Structures

Reconciling Lava Temperatures and Interior Models for Io

Keszthelyi, L.; Milazzo, M.; Jaeger, W L.; Wilson, L.; Mitchell, K L.; Lunar and Planetary Science XXXVI, Part 11; [2005];

The very high temperatures that have been reported for lavas on Io have proven to be difficult to explain In particular,the estimates of lava temperatures of approx 1600 C require that the interior of Io be: (a) largely undifferentiated and (b)almost completely molten However, models of tidal dissipation within Io show that a largely molten interior would notproduce sufficient heat to maintain the observed level of volcanism The latest modeling suggests that Io s mantle should notcontain more than 20% melt If Io s bulk composition is similar to a CM chondrite, then 20% melt implies a lava temperature

of 1200 C This 400 C discrepancy is the focus of this study

Derived from text

Lava; High Temperature; Io

Gravity Models of the Hemispheric Dichotomy in Eastern Mars: Lithospheric Thickness and Subsurface Structure

Kiefer, Walter S.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of theentire parent document

The hemispheric dichotomy of Mars is one of the most prominent topographic structures on the planet, with a typicaloffset of 4 km between the southern highlands and the northern lowlands Various mechanisms have been proposed for formingthe dichotomy, including both internal processes related to mantle convection and external processes related to one or morelarge impacts Gravity and topography observations provide clues that can help to constrain the mechanisms which producedthe dichotomy For example, these observations can constrain the lithospheric thickness and hence the heat flux at the time

of lithospheric loading They can also reveal the presence of possible buried structures In this work, I focus on the dichotomyboundary in eastern Mars between 50o and 155o East longitude In this region, the dichotomy boundary has a roughly linearplanform, striking NW-SE, except where the boundary is affected by the Isidis impact basin The topographic offset across thedichotomy in this part of Mars is relatively scarp-like, with 3 to 4 km of vertical relief occurring across a narrow transitionzone between the southern highlands and the northern lowlands The results reported here are based on the highest resolutiongravity model currently available from the Planetary Data System, JGM95I-01, and include spherical harmonic degrees 2-60(half-wavelength resolution 180 km)

Author

Gravitation; Dichotomies; Mathematical Models; Mars Surface; Lithosphere; Structural Basins; Thickness

20050170602 New Mexico Univ., Albuquerque, NM, USA

Calculations of the Fluxes of 10-250 keV Lunar Leakage Gamma Rays

Kim, K J.; Reedy, R c.; Gasnault, O.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

The gamma rays measured above the surface of planetary objects can be used to study that surface s composition.Previous and current measurements have mainly used gamma rays with energies greater than 500 keV, although most missionsmeasured down to approx 100 keV Gamma rays above approx 100 keV are very penetrating and thus hard to collimate, soprevious missions to the Moon and Mars have measured gamma rays arriving from the entire visible surface The spatialresolution was not better than about the distance above the planet s surface The continua observed on previous missions down

to ~100 keV increases significantly with decreasing energy These continua make it hard to measure the fluxes of gamma-raylines with energies below approx 500 keV, and all elemental analyses have used higher-energy gamma rays, usually using only

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lines The continuum can be used to study components of the lunar composition The lunar continuum is a good measure ofthe abundance of the natural radioactive elements K, U, and Th, using the continuum between 0.55 and 2.75 MeV and between

450 and 480 keV Fourier transforms of continua have been proposed to determine composition

Derived from text

Computation; Flux (Rate); Gamma Rays; Lunar Rays; Flux

20050170603 Purdue Univ., West Lafayette, IN, USA

The Crustal Dichotomy and Edge Driven Convection: A Mechanism for Tharsis Rise Volcanism?

King, S D.; Redmond, H L.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

A vertical wall of constant temperature is a convectively unstable geometry and drives convective motion in the fluid nearthe wall This is the essence of the edge-driven convection hypothesis On Earth small-scale convection could be triggeredfrom the vertical step in the thermo-chemical boundary at cratonic keels and continent-ocean boundaries Seismic evidencesupporting EDC has been observed under the African cratons

Derived from text

Crusts; Dichotomies; Wall Temperature; Volcanology; Mars Surface

20050170604 Washington Univ., Saint Louis, MO, USA

Mountain Building on Io: An Unsteady Relationship Between Volcanism and Tectonism

Kirchoff, M R.; McKinnon, W B.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

Introduction: Most mountains on Io are formed through tectonic mechanisms, since few observed seem to be volcanic.Volcanism may still play an important role in mountain formation, however, e.g., as indicated by the now famous degree-2anticorrelation between mountain and volcano distributions Three major hypotheses for mountain formation that have beenproposed are a) convection-modified subsidence, which states that burial of older volcanic layers by new ones (subsidence)creates large, global compressional stresses, which are modified by degree-2 mantle convection resulting in two broad regionseach of compression and relative tension; b) plume-focused subsidence, where subsidence stresses are focused by upwellingmantle plumes impinging on the base of the crust to produce isolated mountains; and c) thermally-modified subsidence, whichproposes that mountains are formed by a combination of thermal and subsidence stresses, the former created in the crust due

to localized or regional reductions in eruption rates, which cause strong increased conductive heating

Derived from text

Io; Mountains; Volcanoes; Tectonics; Thermal Stresses

RADAR Reveals Titan Topography

Kirk, R L.; Callahan, P.; Seu, R.; Lorenz, R D.; Paganelli, F.; Lopes, R.; Elachi, C.; Lunar and Planetary Science XXXVI,Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains black and white illustrations; Copyright; Avail:CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

The Cassini Titan RADAR Mapper is a K(sub u)-band (13.78 GHz, lambda = 2.17 cm) linear polarized RADARinstrument capable of operating in synthetic aperture (SAR), scatterometer, altimeter and radiometer modes During the firsttargeted flyby of Titan on 26 October, 2004 (referred to as Ta) observations were made in all modes Evidence for topographicrelief based on the Ta altimetry and SAR data are presented here Additional SAR and altimetry observations are planned forthe T3 encounter on 15 February, 2005, but have not been carried out at this writing Results from the T3 encounter relevant

to topography will be included in our presentation Data obtained in the Ta encounter include a SAR image swath

Derived from text

Titan; Topography; Synthetic Apertures; Cassini Mission

MarsLab at the Nevada Test Site: Rover Search for Subsurface Hydrothermal Activity Exposed by Small Craters

Kirkland, L E.; Herr, K C.; Adams, P M.; Prothro, L B.; Allen, B M.; Lunar and Planetary Science XXXVI, Part 11; [2005];

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Hydrothermal alteration products that correlate with ejecta from small craters (less than approx 100 m deep) could flagnear-surface hydrothermal activity An accompanying abstract discusses potential airborne (Mars satellite analog) routes todiscover such sites, based on testing from explosion craters at the Nevada Test Site (NTS) Here we report correlatedground-based studies that use rover-analog, thermal infrared imaging spectroscopy A primary goal of the airborne study is todetermine routes to discovery of hydrothermal activity on Mars The goals of the ground-based study are: (1) determine whichmaterials and textures cause the observed airborne signatures, and which materials are imperceptible; (2) compare the airborneresults to detailed geologic maps; and (3) develop lessons-learned for Mars.

Author

Thermal Mapping; Craters; Infrared Imagery; Mars Surface

The Search for Underground Hydrothermal Activity Using Small Craters: An Example from the Nevada Test Site

Kirkland, L E.; Herr, K C.; Adams, P M.; Prothro, L B.; Allen, B M.; Lunar and Planetary Science XXXVI, Part 11; [2005];

Summary: Craters can create windows into subsurface geology Hydrothermal alteration products that correlate withejecta from small craters (less than 100 m deep) can flag possible near-surface hydrothermal activity A region with suchactivity is a highly prized target for Mars exploration Here we describe an airborne (satellite analog) study that identifiedmineral indicators of hydrothermal activity exposed by manmade explosion craters in a basalt flow Abstract presents therelated ground-based study This field development work draws mainly on operational expertise from outside NASA One goal

is to develop an operational foundation for routes to discovery for Mars

Author

Mars Exploration; Hydrothermal Systems; Craters; Basalt

Antipodal Magnetic Anomalies on the Moon, Contributions from Impact Induced Currents Due to Positive Holes and Flexoelectric Phenomina and Dynamo

Kletetschka, G.; Freund, F.; Wasilewski, P J.; Mikula, V.; Kohout, Tomas; Lunar and Planetary Science XXXVI, Part 11;[2005]; 1 pp.; In English; See also 20050170551; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

Large impacts on the Moon generate large pressure pulses that penetrate the whole body Several of these large impactsmay have generated antipodal structure with anomalous magnetic intensity.These regions can be more than a thousand kmacross, with fields of the order of tens to hundreds of nT This is the case of Orientale, Imbrium, Serenitatis, Crisium, andNectaris impact basins The production of large-scale magnetic fields and associated crustal magnetization due to lunarbasin-forming impacts was hypothesized to have an origin in fields external to the impact plasma cloud that are produced bythe magnetohydrodynamic interaction of the cloud with ambient magnetic fields and plasmas During the period ofcompressed antipodal field amplification, seismic compressional waves from the impact converge at the antipode resulting intransient shock pressures that reach 2 GPa (20 kbar) This can produce conditions for shock magnetic acquisition of the crustantipodal to impact basins

Derived from text

Magnetic Anomalies; Moon; Structural Basins; Transient Pressures; Magnetization

20050170611 NASA Johnson Space Center, Houston, TX, USA

MIMOS II on MER One Year of Mossbauer Spectroscopy on the Surface of Mars: From Jarosite at Meridiani Planum

to Goethite at Gusev Crater

Klingelhoefer, G.; Rodionov, D S.; Morris, R V.; Schroeder, C.; deSouza, P A.; Ming, D W.; Yen, A S.; Bernhardt, B.; Renz,F.; Fleischer, I., et al.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations

Contract(s)/Grant(s): DLR-50QM99022; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only aspart of the entire parent document

The miniaturized Mossbauer (MB) spectrometer MIMOS II [1] is part of the Athena payload of NASA s twin MarsExploration Rovers ‘Spirit’ (MER-A) and ‘Opportunity’ (MER-B) It determines the Fe-bearing mineralogy of Martian soilsand rocks at the Rovers respective landing sites, Gusev crater and Meridiani Planum Both spectrometers performed

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successfully during first year of operation Total integration time is about 49 days for MERA (79 samples) and 34 days forMER-B (85 samples) For curiosity it might be interesting to mention that the total odometry of the oscillating part of the MBdrive exceeds 35 km for both rovers.

Derived from text

Miniaturization; Payloads; Roving Vehicles; Mars Exploration; Landing Sites; Craters

Rock Around the World: Extending a Global Reach to Involve Students in Science Using Infrared Research at Mars

Klug, S L.; Christensen, P R.; Rogers, L.; Gorelick, N.; Rogers, D.; Jones, B.; Brindley, T.; Rogers, T.; Ki, J.; Staley, L., etal.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

The Rock Around the World Program (RATW) began with a blending of desired outcomes from two disciplines - scienceand education First, as an extension of the ASU Mars Education Program, there was a desire to inspire students to becomemore interested in science The premise was that kids of all ages like space and, in turn, kids like Mars Using the lure of Mars

to get them interested in science seemed like a good plan Secondly, there was a desire from the ASU Mars science team tocollect more rock samples from around the world to expand the earth-based rock library at Arizona State University Thislibrary currently supports research that is being conducted by the Thermal Emission Spectrometer (TES), the ThermalEmission Imaging System (THEMIS) - both in orbit around Mars, and the two Mini-Thermal Emission Spectrometer(Mini-TES) instruments onboard the Mars Exploration Rovers on the surface of Mars All of these instruments are currentlybeing used to study rocks on Mars The Rock Around the World Program evolved from these beginning ideas and has become

an inspiration to all involved

Derived from text

Infrared Radiation; Mars Exploration; Mars Surface; Education

20050170613 European Space Agency European Space Research and Technology Center, ESTEC, Noordwijk, Netherlands

The ESA Exploration Programme: Exomars and Beyond

Kminek, G.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 1 pp.; In English; See also 20050170551; Copyright;Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

The countries participating in the European Exploration Programme Aurora have recently confirmed and increased theircontribution The ESA Council has later approved the Agency s budgets for 2005, including the budget for Aurora Thesedevelopments enable major industrial activities to continue in line with original plans These include work on the ExoMarsmission and the Mars Sample Return mission, in-orbit assembly, rendezvous and docking, habitation and life support systemsplus a broad range of technology development work The Aurora Exploration Programme has been integrated into the HumanSpaceflight and Microgravity Directorate , which now forms the Human Spaceflight, Microgravity, and ExplorationDirectorate of ESA

Derived from text

European Space Agency; Mars Sample Return Missions; Life Support Systems; Space Flight; Orbital Rendezvous; Microgravity

20050170614 Tokyo Inst of Tech., Tokyo, Japan

Presolar Silicate Grains from Primitive Carbonaceous Chondrites Y-81025, ALHA 77307, Adelaide and Acfer 094

Kobayashi, S.; Tonotani, A.; Sakamoto, N.; Nagashima, K.; Yurimoto, H.; Krot, A N.; Lunar and Planetary Science XXXVI,Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains black and white illustrations; Copyright; Avail:CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

Recently presolar silicates were found in a few meteorites, Acfer 094 (ungrouped type 3), NWA 530 (CR2), Bishunpur(LL3.1) and Semarkona (LL3.0) Acfer 094 which is thought to be the most pristine chondrite represents the highestabundance of approximately 40, 30 and 110 ppm Some researchers suggest that there are some effects of alteration andmetamorphism in matrix even in the petrologic subtype 3.0 chondrites Therefore, it is unclear for the effect of alteration andmetamorphism against the submicron order of presolar silicates even in type-3 chondrites In this study we report the presolarsilicates from the least altered and metamorphosed carbonaceous chondrites, Y-81025 (CO3.0), ALHA 77307 (CO3.0),Adelaide (ungrouped, linked to CV-CO) and Acfer 094 (ungrouped, linked to CO-CM), which there are some agreement thatthe above chondrites are one of the most pristine chondrites

Derived from text

Carbonaceous Chondrites; Silicates; Metamorphism (Geology); Granular Materials

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20050170615 Japan Aerospace Exploration Agency, Ibaraki, Japan

Mare Volcanism on the Moon Inferred from Clementine UVVIS Data

Kodama, S.; Yamaguchi, Y.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

The compositional distribution and the stratigraphy of the mare basalts are important to our understanding of thecomposition of the lunar interior and its thermal evolution Previous works using the Earth-based telescopes or remote sensingdata revealed a large variation in the composition of mare basalts, and suggested that the basin-scale mare volcanism evolvedindependently of neighboring regions It is therefore necessary to know the chemical properties of mare basalts, together withtheir detailed distribution and stratigraphy in each region, and to understand how the mare volcanism evolved compositionallyand spatially in a basin For these purpose, we have mapped the mare basalts on the nearside of the Moon using the ClementineUVVIS multi-spectral images, and construct their stratigraphy This paper presents the result of Oceanus Procellarum andMare Imbrium, and discusses the temporal and spatial variations of the mare volcanism of this area and the eastern nearsideregion

Author (revised)

Clementine Spacecraft; Lunar Maria; Moon; Volcanology; Ultraviolet Radiation; Light (Visible Radiation)

Public Outreach and Archiving of Data from the High Resolution Stereo Camera Onboard Mars Express: 2004 The First Year

Koehler, U.; Neukum, G.; Gasselt, S v.; Jaumann, R.; Roatsch, Th.; Hoffmann, H.; Zender, J.; Acton, C.; Drigani, F.; Lunarand Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentDuring the first year of operation, corresponding to the calendar year 2004, the HRSC imaging experiment onboard ESA’sMars Express mission recorded 23 Gigabyte of 8-bit compressed raw data After processing, the amount of data increased tomore than 344 Gigabyte of decompressed and radiometrically calibrated scientifically useable image products Every sixmonths these HRSC Level 2 data are fed into ESA’s Planetary Science Archive (PSA) that sends all data also to the PlanetaryData System (PDS) to ensure easy availability to the interested user On their respective web portals, the European SpaceAgency published in cooperation with the Principal Investigator-Group at Freie Universitat Berlin and the German SpaceAgency (DLR) almost 40 sets of high-level image scenes and movies for PR needs that have been electronically visited manyhundred thousand times

Derived from text

Cameras; High Resolution; Mars Express; Stereophotography; Data Processing

Determination of Meteorite Porosity Using Liquid Nitrogen

Kohout, T.; Kletetschka, G.; Pesonen, L J.; Wasilewski, P J.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 1 pp.;

In English; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

We introduce a new harmless method for porosity measurement suitable for meteorite samples The method is amodification of the traditional Archimedean method based on immersion of the samples in a liquid medium like water ororganic liquids In our case we used liquid nitrogen for its chemically inert characteristics

Derived from text

Liquid Nitrogen; Meteorites; Porosity

20050170618 Tokyo Univ., Japan

Crystallization Experiment of Los Angeles Basaltic Shergottite: Implication for the Crystallization of Los Angeles and Dhofar 378

Koizumi, E.; Mikouchi, T.; Chokai, J.; Miyamoto, M.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; InEnglish; See also 20050170551; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

Los Angeles (LA) is a coarse grained basaltic shergottite composed of pyroxene and maskelynite Pyroxenes in thismeteorite are pigeonite and augite, and both pyroxenes are extensively zoned from relatively Mg-rich cores to Ferich rims

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The Ca zoning pattern is complex and pigeonite and augite are irregularly distributed unlike other basaltic shergottites.Previous study interpreted this irregular zoning as the result of exsolution at low temperature Because LA has high plagioclaseabundance similar to QUE94201, there is a possibility that the LA bulk composition represents a parent melt composition.However, these two shergottites show distinct pyroxene zoning patterns although their compositions are generally similar Inthis study, we performed a crystallization experiment using the LA bulk composition to investigate the crystallization history

of LA We also compared LA mineralogy with that of Dhofar 378 (DHO) which shows a lot of mineralogical characteristicssimilar to LA, and applied the experimental result to explain the differences between LA and DHO

Derived from text

Basalt; Crystallization; Mineralogy; Shergottites; California

Chasmata of Planum Australe, Mars: Are Their Formation and Location Structurally Controlled?

Kolb, E J.; Tanaka, K L.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

The chasmata within Mars south pole ice cap of Planum Australe are indicators of large-scale erosional episodes that haveresulted in the removal of greater than kilometer-thick stacks of south polar layered deposits (SPLD) Geologic mapping of

a large trough system located between two of the chasmata indicates that the trough’s location and erosional morphologiesare in large part, structurally controlled by SPLD bedding attitudes The scarps of Promethei and Ultimum Chasma also revealdipping SPLD beds Therefore, to what degree is the location of these chasmata and their formation history controlled bySPLD bedding and (or) substrate topography? We have undertaken a detailed geologic mapping study of the chasmata usingMars Global Surveyor (MGS) and Mars Odyssey (MO) datasets to determine their bedding features, formation mechanisms,and emplacement timing Syntheses of these observations allow discrimination and characterization of potential structuralcontrols over chasma formation This study is part of our 1:1.5M-scale geologic mapping project of Mars north and south polarice deposits A general review of the mapping results is included

Derived from text

Mars Surface; Planetary Geology; Topography; Plains

Compositions of Three Lunar Meteorites: Meteorite Hills 01210, Northeast Africa 001, and Northwest Africa 3136

Korotev, R L.; Irving, A J.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Original contains color illustrations

Contract(s)/Grant(s): NNG04GG10G; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only aspart of the entire parent document

We report on compositions obtained by instrumental neutron activation analysis on three new lunar meteorites, MET

01210 (Meteorite Hills, Antarctica; 23 g), NEA 001 (Northeast Africa, Sudan; 262 g), and NWA 3136 (Northwest Africa,Algeria or Morocco; 95 g) As in previous similar studies, we divided our samples into many (8-9) small (approximately 30mg) subsamples prior to analysis

Derived from text

Africa; Lunar Surface; Meteoritic Composition

20050170622 Oulu Univ., Finland

Anomalous Depressions on the Circum-Hellas Crater Floors as Seen in the First Year MEX HRSC Images

Korteniemi, J.; Lahtela, H.; Raitala, J.; Neukum, G.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English;See also 20050170551; Original contains color and black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

The surface of Mars is divided into smooth northern lowlands and cratered southern highlands The cratering recordindicates the age of the surface, while the original morphology of individual craters hints to the target material Furthermore,craters provide a natural basin for later deposits, thus showing glimpses of the regional evolution The 2000 km Hellas impactbasin dominates about half of the southern hemisphere of Mars The region has numerous volcanic, tectonic, glacial, fluvialand aeolian features, as well as a multitude of large and small impact craters Fresh large (greater than 5 km) Martian cratershave typically raised rims, a central peak and/or a peak ring and a generally flat floor with slumping on the inner walls Theadditional central or summit pits are common features on Martian craters, and generally related to high volatile content of the

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target material These features are subsequently modified and smoothened by later geological processes characteristical for thearea, e.g erosion, sedimentation and impact cratering One type of post-impact modification is the creation of depressions onthe crater floor Such features include pits, large scale fractures and, in some cases, more complex depressions such ashoneycomb-like ridges with intervening pits Continuing our study of these anomalous crater floors, we map the structures inthe Hellas region using the High Resolution Stereo Color (HRSC) images obtained in 2004 HRSC provides multiple channelsand improved accuracy (10-60m/pix) compared to the previous data sets with related areal coverage.

Derived from text

High Resolution; Mars Craters; Mars Surface; Stereophotography; Anomalies; Structural Basins; Mars Volcanoes

20050170623 Planetary Science Inst., Tucson, AZ, USA

The Fate of Neptune’s Primordial Trojan Companions Lost During Planetary Migration

Kortenkamp, Steve; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document

An earlier paper (Kortenkamp et al 2004) investigated the survivability of Trojan type companions of Neptune duringprimordial radial migration of the giant planets Jupiter, Saturn, Uranus, and Neptune A standard planet migration model wasused in which the migration speed decreases exponentially with a characteristic time scale A series of numerical simulationswere performed, each involving the migrating giant planets plus 1000 test particle Neptune Trojans with initial distributions

of orbital eccentricity, inclination, and libration amplitude similar to those of the known jovian Trojans asteroids Thesimulations were analyzed to measure the survivability of Neptune’s Trojans as a function of migration rate The results ofthis analysis are summarized in this paper

Derived from text

Asteroids; Gas Giant Planets; Planetary Geology; Neptune (Planet)

20050170628 Hokkaido Univ., Sapporo, Japan

Chaotic Occurrence of Some Deep Moonquakes

Koyama, Junji; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Originalcontains color illustrations; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of theentire parent document

Seismic observation on the Moon during the Apollo project from 1969 to 1977 discovered tidally induced moonquakesoccurring at depths about halfway to the center of the Moon [1] Deep moonquakes were characterized by identical waveforms

at a given station observed at near monthly intervals[2] The identification of these deep moonquakes and also other eventswas made by the visual inspection of long-period seismograms, resulting in 12,558 catalogued events [3] A new computeranalysis of the Apollo lunar seismic data set using a combination of waveform cross-correlation and single-link cluster analysis[4] revealed that about 60% of the identified and catalogued events are deep moonquakes, and increased the number ofidentified deep moonquakes by more than a factor of five We have applied a simple nonlinear method of Poincare map to timedistribution of events listed in the new catalogue and it reveals previously undetected features of hidden periodic components

on the deep moonquake activity

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Moonquakes; Seismology; Cluster Analysis; Temporal Distribution; Visual Observation

20050170629 Notre Dame Univ., IN, USA

Distinguishing High-Al Mare Basalt Units Using High Resolution Clementine Data

Kramer, Georgiana Y.; Jolliff, Bradley L.; Neal, Clive R.; Kirkland, Laurel; Fessler, Brian; Lunar and Planetary ScienceXXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color and black and white illustrations;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentThe Apollo 14 high-Al basalts have a complex petrologic history (see [1]) and unique source, which may be specific toall high-Al basalts They are low in Ti, and distinct from other low-Ti mare basalts by their higher alumina content (12 - 15wt% Al2O3 compared to 7 - 12 wt% Al2O3) Other key oxide concentrations include MgO=7-12 wt%, FeO=13-17 wt%,TiO2=1.5-3 wt%, and incompatible elements 10 to 100 times chondrite, (e.g., Th concentrations are 0.1-3 ppm) Some of thehigh-Al basalts are old (\g4 Ga), and the sample data suggests there are at least three and possibly five distinct sources andepisodes of volcanism represented at the Apollo 14 site alone [1] Exposures of these basalts near the Apollo 14 are likelymasked by ejecta from the Imbrium impact, which is responsible for the formation of the Apollo 14 breccias and post-dateseruption of the basalts This suggests that they could be a significant component of ancient basalts that are now buried beneath

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impact deposits (cryptomare) The existence of younger aluminous basalts at the Apollo 12 and Luna 16 sites suggest thataluminous basaltic volcanism spanned over a billion years [2,3].

Derived from text

Aluminum Oxides; Basalt; Chondrites; Deposits

Overview of Results from the Cassini Magnetospheric Imaging Instrument (MIMI) During the First Year of Operations

Krimigis, S M.; Mitchell, D G.; Hamilton, D C.; Krupp, N.; Livi, S.; Roelof, E C.; Dandouras, J.; Mauk, B H.; Brandt, J.P.; Paranicas, C., et al.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 1 pp.; In English; See also 20050170551;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentThe MIMI investigation comprises three sensors covering the indicated energy ranges: the Ion and Neutral Camera(INCA) 7 keV/nuc \hE\h200 keV/nuc (ions/neutrals): Charge-Energy-Mass-Spectrometer (CHEMS) 3\hE\h230 keV/e(ions),, and Low Energy Magnetospheric Measurement System (LEMMS) 0.02 \hE\h18 Mev (ions)/0.015 \hE\h1 Mev(electrons) Also, LEMMS measures high-energy electrons (E\g3 Mev) and protons (1.6 \h E \h 160 Mev) from the back end

of the dual field-of-view telescope The Saturn observation sequences began in January, 2004 and culminated in Saturn OrbitInsertion on July 1, 2004 The MIMI sensors observed substantial activity in interplanetary space for several months prior toSOI, including several interplanetary shocks associated with corotating interaction regions, numerous increases most likelyoriginating from particle streams in the vicinity of the Saturnian bow shock and energetic neutral atoms (ENA) emanatingfrom Saturn s magnetosphere Results following SOI revealed: a dynamical magnetosphere with a day-night asymmetry and

an 11-hour periodicity; several water-product ions (O+, OH+, H2O+), but little N+; inferred quantities of neutral gas sufficient

to cause major losses in the trapped ions and electrons in the middle and inner magnetosphere; a Titan exosphere that is acopious source of ENA; INCA imaging through ENA has also revealed a previously unknown radiation belt residing inward

of the D-ring that is most likely the result of double charge-exchange between the main radiation belt and the upper layers

of Saturn s exosphere Finally, there is ample evidence for the presence of substorm-like injections of plasma that subsequentlycorotates for a number of days before dissipating on the night-side magnetotail The observations will be presented anddiscussed in the context of current theoretical models

Derived from text

Imaging Techniques; Field of View; Mass Spectrometers; Charge Transfer; Magnetic Storms; Shock Waves; Neutral Gases

Global Winds and Aerosol Updrafts Created by the Chicxulub Impact Event

Kring, David A.; Showman, Adam P.; Durda, Daniel D.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; InEnglish; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part ofthe entire parent document

The iridium-rich layer at the Cretaceous-Tertiary boundary indicates high-energy ejecta from the Chicxulub crater rainedthrough the atmosphere after the impact The energy deposited by the debris warmed the atmosphere over continent-sizedareas near the impact site and antipode The thermal contrast with the surrounding atmosphere generated winds aloft withspeeds of approx.80 m/sec to near-supersonic values of 255 m/sec These winds, in turn, drove surface winds that could havereached hurricane strength over broad regions Within those regions, the tropopause was temporarily destroyed and aerosols(sea salt, soil dust, soot from fires) were swept from the troposphere into the stratosphere

Derived from text

Aerosols; Winds Aloft; Cretaceous-Tertiary Boundary; Atmospheric Circulation; Ground Wind; Craters

20050170634 Hawaii Univ., Honolulu, HI, USA

Relative Chronology of CAI and Chondrule Formation: Evidence from Chondrule-bearing Igneous CAIs

Krot, a N.; Yurimoto, H.; Hutcheon, I D.; MacPherson, G J.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.;

In English; See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part

Chondrules and CAIs are the major high temperature chondritic components formed during transient heating events in thesolar nebula approx.4.57 billion years ago [1,2] One of the major questions in meteoritics concerning the origin of CAIs andchondrules is their relative chronology Most CAIs show large Mg-26 excesses (Mg*-26) corresponding to an initialAl-26/Al-27 ratio [(Al-26/Al-27)0] of approx.5 10(exp -5) [3,4], whereas most chondrules have smaller Mg*-26

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corresponding to (Al-26/Al-27)0 of less than or equal to 1.2 10(exp -5) [5-7] Based on these observations and the assumptionthat Al-26 was uniformly distributed in the solar nebula, it is generally inferred that CAIs formed at least 1-1.5 Myr beforechondrules This conclusion has recently been questioned based on new Pb [2] and Mg isotope measurements [4] ThePb-207-Pb-206 ages of the Allende chondrules (4566.7+/-1.0 Ma) cannot be distinguished from those of the CV CAIs(4567.2+/-0.6 Ma) [1,2] Bizzarro et al [4] reported a range of (Al-26/Al-27)0 from (5.66+/-0.80) to (1.36+/-0.52) 10(exp -5)

in the bulk Allende chondrules and concluded that chondrule formation began contemporaneously with the formation of CAIs,and continued for at least 1.4 Myr We note, however, that the (Al-26/Al-27)0 ratios inferred from bulk Mg isotopemeasurements of chondrules may date the time for the formation of chondrule precursor materials, not the time of chondrulemelting; the latter requires Mg isotope measurements of mineral separates or individual mineral grains, which have not beendone yet In addition, spatial heterogeneity of 26Al in the solar nebula cannot be ruled out

Derived from text

Aluminum Isotopes; Chondrites; Chondrule; Meteoritic Composition; Meteorites; Magnesium Isotopes; Solar Nebula

Extracting Olivine (Fo-Fa) Compositions from Raman Spectral Peak Positions

Kuebler, K.; Jolliff, B J.; Wang, Alian; Haskin, L A.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English;See also 20050170551

Contract(s)/Grant(s): NAG5-12114; NAG5-10703; NAG5-12684; Copyright; Avail: CASI;A01, Hardcopy; Available fromCASI on CD-ROM only as part of the entire parent document

Olivine and pyroxene are two major basaltic minerals that have been identified at Gusev Crater and Meridiani Planum

by the Mars Exploration Rovers Full petrologic characterization of a sample (rock or soil), however, requires determining therange of mineral compositions, extent of zoning, range of grain sizes, mineral associations, presence of xenocrysts, etc.Information of this sort will aid the interpretation of sample crystallization and differentiation histories and help discriminatebetween lithologies In Raman spectroscopic experiments, minerals are identified by their spectral patterns and mineralcompositions can be inferred from the peak positions Instruments currently in use or slated for impending surface explorationmissions provide only average elemental compositions for relatively large rock or soil targets or bulk mineral analysis Notechniques currently in use or scheduled for flight can characterize both structure and composition of individual mineral grains,in-situ, like the Mars Microbeam Raman Spectrometer (MMRS) The MMRS is designed to take 100 spectra along a 1 cmlinear traverse on the surface of a sample, with contributions from one or a few mineral phases per spectrum We presented

a method to extract structural and compositional information from the Raman spectra of quadrilateral pyroxenes The pyroxenecalibration was applied to a Raman spectroscopic study of Martian meteorite EETA79001 along with a preliminary olivinecalibration, where we demonstrated the capability to discriminate related lithologies using Raman point counts This paperpresents an improved olivine calibration that will further aid sample characterization and the study of alteration processes.Derived from text

Mineralogy; Olivine; Pyroxenes; Mars Surface; Chemical Composition

Detailed Results on Analyses of Deposits of the Eltanin Impact, Recovered in Sediment Cores from Polarstern Expedition ANT-XVIII/5a

Kyte, Frank T.; Gersonde, Rainer; Kuhn, Gerhard; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English;See also 20050170551; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entireparent document

Deposits of the late Pliocene (2.5 Ma) Eltanin impact are unique in the known geological record This is the only knownexample of a km-sized asteroid that impacted a deep-ocean (5 km) basin, and the central portion of the impact region is themost meterorite-rich locality known on Earth Evidence for this deposit was first discovered as an Ir anomaly in sedimentsfrom three cores collected in 1965 [1,2] by the USNS Eltanin These cores were also found to contain mm-sized shock-meltedasteroidal materials and several percent unmelted meteorite fragments [3] Based on mineral chemistry of unmelted meteoritefragments, and siderophole element concentrations in the impact melt, the parent asteroid is considered to be a low-metal(approx.4%) mesosiderite [4,5]

Derived from text

Deposits; Sediments; Impact Melts; Iron Meteorites; Meteoritic Composition; Asteroids

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20050170638 Wien Univ., Austria

Silicate Inclusions in the Kodaikanal IIE Iron Meteorite

Kurat, G.; Varela, M E.; Zinner, E.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also20050170551; Original contains color and black and white illustrations

Contract(s)/Grant(s): NNG04GG49G.; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only aspart of the entire parent document

Silicate inclusions in iron meteorites display an astonishing chemical and mineralogical variety, ranging from chondritic

to highly fractionated, silica- and alkali-rich assemblages In spite of this, their origin is commonly considered to be a simpleone: mixing of silicates, fractionated or unfractionated, with metal The latter had to be liquid in order to accommodate theformer in a pore-free way which all models accomplish by assuming shock melting II-E iron meteorites are particularlyinteresting because they contain an exotic zoo of silicate inclusions, including some chemically strongly fractionated ones.They also pose a formidable conundrum: young silicates are enclosed by very old metal This and many other incompatibilitiesbetween models and reality forced the formulation of an alternative genetic model for irons Here we present preliminaryfindings in our study of Kodaikanal silicate inclusions

Derived from text

Inclusions; Iron Meteorites; Mineralogy; Silicates

20050170639 Academy of Sciences (Russia), Moscow, Russia

Seasonal Redistribution of Water in the Surficial Martian Regolith: Results of the HEND Data Analysis

Kuzmin, R O.; Zabalueva, E V.; Mitrofanov, I G.; Litvak, M I.; Parshukov, A V.; Grinkov, V Yu.; Saunders, R S.; Boynton,W.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains colorillustrations

Contract(s)/Grant(s): RFBR Proj N 03-02-16644; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

The global mapping of the neutrons emission from the Mars, conducted recently by HEND instrument (Mars Odyssey),has shown that the surface layer (1-2 m) on the high latitudes of the planet (up to 50 ) is very reached by water ice withabundance more 50% by mass [1,2,3 ] It was also shown that water ice distribution in surficial layer of the northern and thesouthern sub-polar regions is notably different [4] Until today the existing HEND data already covers the period more thenone the Martian year This let to study the seasonal effects of volatiles redistribution associated with processes of sublimationand condensation of the seasonal polar caps and water exchange between the surface regolith and atmosphere The goal of ourwork was to analyze the dynamic of the globally mapped neutrons flux as key to understanding of the seasonal redistribution

of the water ice in the surface layer For this we analyzed the globally mapped flux of the neutrons with different energy andcorresponding effective layer of their emission

Derived from text

Mapping; Emission; Surface Layers; Neutrons; Mars (Planet); Regolith

Lunar and Planetary Science XXXVI, Part 12

[2005]; ISSN 1540-7845; In English; Lunar and Planetary Science XXXVI, 14-17 Mar 2005, Houston, TX, USA; See also

20050170943 - 20050171009

Contract(s)/Grant(s): NCC5-679

Report No.(s): LPI-Contrib-1234-Pt-12; Copyright; Avail: CASI;C01, CD-ROM

Topics discussed include: The Ancient Lakes in Hellas Basin Region as Seen Through the First Year of Mars ExpressHRSC-Camera; DISR Observations of Craters at Titan at the Huygens Landing Site: Insights Anticipated; The Sun s Dust Disk

- Discovery Potential of the New Horizons Mission During Interplanetary Cruise; Evidence for Aqueously PrecipitatedSulfates in Northeast Meridiani Using THEMIS and TES Data; Integrated Spectroscopic Studies of Anhydrous SulfateMinerals; Venusian Channel Formation as a Subsurface Process; Reexamination of Quartz Grains from the Permian-TriassicBoundary Section at Graphite Peak, Antarctica; Observations of Calcium Sulfate Deposits at High Latitudes by OMEGA/Mex

at Km/Pixel Resolutions; Observations of the North Permanent Cap of Mars in Mid-Summer by OMEGA/MEX at km perPixel Resolutions; Classification and Distribution of Patterned Ground in the Southern Hemisphere of Mars Genesis:Removing Contamination from Sample Collectors; Thermal Characterization of Fe3O4 Nanoparticles Formed from PoorlyCrystalline Siderite; Hydrogen Abundances in Metal Grains from the Hammadah Al Hamra (HaH) 237 Metal-rich Chondrite:

A Test of the Nebular-Formation Theory; REE and Some Other Trace Elements Distributions of Mineral Separates in Atlanta(EL6); The Composition and Origin of the Dewar Geochemical Anomaly; Asteroid Modal Mineralogy Using Hapke Mixing

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Models: Testing the Utility of Spectral Lookup Tables; and The Huygens Mission at Titan: Results Highlights (sup182)Hf-(sup 182)W Chronometry and an Early Differentiation in the Parent Body of Ureilites Ground Penetrating Radar inSedimentary Rocks Mars, Always Cold, Sometimes Wet: New Constraints on Mars Denudation Rates and Climate Evolutionfrom Analog Studies at Haughton Crater, Devon Island, High Arctic Europa s Porous Ice Rheology and Implications forIce-penetrating Radar Scattering Loss Surface Generated Cracks on Europa

Derived from text

Abundance; Asteroids; Classifications; Cryogenic Equipment; Craters; Mars Surface; Metal-Gas Systems; Mineralogy; Sedimentary Rocks; Trace Elements; Ureilites; Venus (Planet)

DISR Observations of Craters at Titan at the Huygens Landing Site: Insights Anticipated

Lanagan, P D.; Smith, P H.; Tomasko, M.; Doose, L R.; Rizk, B.; Lunar and Planetary Science XXXVI, Part 12; [2005];

2 pp.; In English; See also 20050170942; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only

as part of the entire parent document

Observations of impact craters have been used to provide constraints on geologic and atmospheric processes active onsolar system surfaces Images to be obtained by the Huygens s probe Descent Imager/Spectral Radiometer (DISR) [1] mayprovide the first close-up look at Titan s impact craters This work lays out a road map for such analysis

Derived from text

Craters; Huygens Probe; Titan; Descent; Spectra

20050170944 Hawaii Univ., Honolulu, HI, USA

The Composition and Origin of the Dewar Geochemical Anomaly

Lawrence, S J.; Hawke, B R.; Lawrence, D J.; Gillis, J J.; Lucey, P G.; Smith, G A.; Taylor, G J.; Lunar and PlanetaryScience XXXVI, Part 12; [2005]; 2 pp.; In English; See also 20050170942; Original contains black and white illustrations;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentDewar is an Imbrian-aged crater located on the lunar farside (2.7 deg S, 165.5 deg E) Recently, D Lawrence et al.reported a thorium enhancement centered northeast of the crater and used FeO mapping algorithms to determine that theposition of the thorium enhancement correlates with an area of relatively high FeO values Here, we report the results of aremote sensing investigation of the Dewar crater area, and place new constraints upon the probable modes of origin for theDewar geochemical anomaly Additional information is included in the original extended abstract

Author (revised)

Lunar Craters; Lunar Far Side; Lunar Composition; Anomalies

20050170945 Institut de Physique du Globe, Paris, France

The Asymmetric Cratering History of the Moon

LeFeuvre, M.; Wieczorek, M A.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 2 pp.; In English; See also20050170942; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI onCD-ROM only as part of the entire parent document

The geologic history of the Moon plays a key role in planetary science as it is the only body for which geologic units havebeen sampled and dated By calibrating the observed size-frequency distribution of impact craters at the Apollo sites to theirradiometric ages, it is possible to determine the ages of other geologic units on the Moon and other planetary bodies TheMoon, however, is not so neutral a reference body as one would hope Because it is locked in a synchronous rotation aboutthe Earth, we have found that it experiences a significant asymmetry in its cratering rate, and that this asymmetry may inducedramatic errors when dating surfaces far from the Apollo landing sites

Author

Asymmetry; Cratering; Paleontology; Chronology; Calibrating; Moon

Evidence for Remnants of Late Hesperian Ice-rich Deposits in the Mangala Valles Outflow Channel

Levy, Joseph S.; Head, James W.; Marchant, David R.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 2 pp.; InEnglish; See also 20050170942; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

New high-resolution images from MGS and Odyssey reveal an unusual unit on the floor of the Mangala Valles outflow

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channel In contrast to abundant terrain showing scour and hydrodynamic shaping typical of the floors and margins of MangalaValles and other outflow channels, this unit is smooth-surfaced, has arcuate and cuspate margins, and has a host of unusualsurface features including round pits We assess several possible origins for this unit and the associated features, and concludethat the most plausible explanation is an ice-rich remnant created by a combination of ponding and ice-cover deflation duringthe waning stages of the outflow channel flood emplacement.

Derived from text

Mars Surface; Mineral Deposits; Ice Formation; Channel Flow

FeO-rich Xenoliths in the Staroye Pesyanoe Aubrite

Lorenz, C A.; Ivanova, M A.; Kurat, G.; Brandstaetter, F.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 2 pp.; InEnglish; See also 20050170942; Original contains black and white illustrations; Copyright; Avail: CASI;A01, Hardcopy;Available from CASI on CD-ROM only as part of the entire parent document

The Staroye Pesyanoe aubrite (SP) is a polymict gas-rich breccia, consists predominantly of enstatite but contains alsoabundant forsterite, albitic feldspar, glasses and glass spherules We analysed five polished sections (2.8 square centimeterstotal sample area) with optical microscopy, ASEM, and EMP, and found nine non-aubritic, FeO-rich minerals and lithic clasts,possibly related to ordinary chondrites (OC) and carbonaceous chondrites (CC) The xenoliths demonstrate accretion ofchondrite-like particles onto the surface of the aubrite parent body (APB) However, the flux of interplanetary dust seems tohave been different from that on the HED parent body and Earth by composition and intensity It could indicate that the APBsampled the dust at a different time or moved through a different region of the Solar System than did the HED parent bodyand the Earth

Derived from text

Meteoritic Composition; Iron Oxides; Mineralogy; Igneous Rocks; Achondrites

Origin of the Lunar Highland Crust

Lowman, P D., Jr.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 1 pp.; In English; See also 20050170942;Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent documentUnderstanding the origin of the oldest lunar crust was a main scientific objective of the last three Apollo missions, 15,

16, and 17, all of which landed in or near highland exposures Starting with Apollo 15, the astronauts took hundreds of 70

mm surface photographs These pictures have been re-studied, and reveal pervasive layering in the lunar highland crust visited

by the Apollo 15, 16, and 17 missions Additional information is included in the original extended abstract

Author (revised)

Lunar Crust; Highlands; Photogeology; Lunar Photography

Formation of Methane on Mars by Fluid-Rock Interaction in the Crust

Lyons, J R.; Manning, C E.; Nimmo, F.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 2 pp.; In English; See also20050170942; Copyright; Avail: CASI;A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parentdocument

Recent spectroscopic detections of CH4 in the atmosphere of Mars are the first definitive observations of an organiccompound on that planet The relatively short photochemical lifetime of CH4 (approx.300 years) argues for a geologicallyyoung source We demonstrate here that low-temperature alteration of basaltic crust by carbon-bearing hydrothermal fluid canproduce the required CH4 flux of 1 x 10(exp 7) moles/year, assuming conservative values for crustal permeability and oxygenfugacity as implied by martian basaltic meteorites The crustal thermal disturbance due to a single dike approx 10 x 1 x 10

km during the past 10(exp 4) years is capable of driving the alteration, if all carbon is supplied by magmatic degassing from

a dike with only 50 ppm C Atmospheric methane strongly suggests ongoing magmatism and hydrothermal alteration on Mars.Derived from text

Methane; Mars Atmosphere; Igneous Rocks; Crusts; Basalt; Planetary Geology; Photochemical Reactions

Tiêu đề	Elastic Thickness Estimates for Coronae Associated with Chasmata on Venus
Tác giả	Hoogenboom, T., Martin, P., Housean, G. A.
Trường học	California Institute of Technology
Chuyên ngành	Planetary Geology
Thể loại	Research report
Năm xuất bản	2005
Thành phố	Pasadena

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