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Geological SurveyCategory: Organizations, agencies, and programs Date: Established March 3, 1879 The scientific and resource management accomplish-ments of the United States Geological

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U.S Geological Survey

Category: Organizations, agencies, and programs

Date: Established March 3, 1879

The scientific and resource management

accomplish-ments of the United States Geological Survey (USGS)

are global in their applications The USGS provides

scientific services to more than one hundred countries.

In addition, USGS scientists and technicians

con-tinue to develop analytical techniques and

instrumen-tation in order to provide reliable scientific data to help

world leaders make decisions.

Background

The policy of westward expansion of the early United

States created the need for more precise maps and an

accurate assessment of the mineral wealth and natural

resources of these lands In 1803, Thomas Jefferson

authorized the purchase of the Louisiana Territory

from France and, in the process, nearly doubled the

size of the country In an attempt to assess what the

U.S had purchased, Jefferson commissioned

Meri-wether Lewis and William Clark to explore the

north-western portion of the territory as far as the Pacific

Ocean Upon their return, Lewis and Clark provided

maps and scientific reports describing all the wonders

they had seen during the expedition Further

explo-ration of the Louisiana Territory took Zebulon Pike

west into Colorado and New Mexico All of these

ex-peditions demonstrated clearly the economic

poten-tial of the region They also highlighted the need for

additional scientific knowledge of these lands and for

more detailed maps to aid future settlers

Prior to the creation of the USGS in 1879, scientific

investigations of natural resources were considered

the responsibility of individual states or private

orga-nizations In 1836, Congress authorized a scientific

expedition, the United States Exploring Expedition,

to the Pacific to evaluate the potential of its

commer-cial resources Then in 1838, Congress established the

Corps of Topographical Engineers to explore and

map the continent For the following twenty years the

corps geologists explored and studied the Western

wilderness In addition to their mapping activities, the

Corps of Topographical Engineers also participated

in the search for possible routes for the future

trans-continental railroads Commercial interest in this

po-tential wealth grew steadily as these explorers

pub-lished their reports This increased interest in mining and mineral resources prompted several states to es-tablish geological surveys to assess land usage and ex-plore for mineral deposits The California gold rush

of 1849 was the main event that caught the public’s attention and beckoned the easterner to head west and “strike it rich.” The large number of people stak-ing claims to minstak-ing sites, followed by the inevitable land disputes, demanded some kind of governmental intervention In response, the U.S government estab-lished the Department of the Interior to deal with issues pertaining to land ownership and natural re-sources

The USGS was formed as the result of a merger of separate surveys conducted under the authority of the Department of War and the Department of the In-terior These early surveys were the Geological Explo-ration of the Fortieth Parallel, the Geological and Geographical Survey of the Rocky Mountain Region, and the Geographical Survey Expedition West of the One Hundredth Meridian This USGS was directed to conduct research in mining geology The first direc-tor was Clarence King He essentially organized the USGS into a bureau that primarily dealt with the west-ern states In 1881, John Wesley Powell became the second director Under his leadership the USGS ex-tended its activities to include the eastern states, thus making it a national organization

The USGS’s activities are not limited to the conti-nental United States and its territories In 1897, par-ticipation in international ventures began by helping scientists find the best location for the proposed route through Nicaragua for a canal linking the Caribbean Sea with the Pacific Ocean (a proposal that eventually led to the Panama Canal) Following the Spanish-American War of 1898, USGS geologists traveled to the Philippines and Cuba to create topographical and geological maps and to assess the potential for finding sources of industrial raw materials The USGS’s areas

of scientific interest were expanding rapidly, well be-yond the traditional boundaries of the United States World Wars I and II placed additional demands on USGS scientists to find national and international sources of strategic natural resources to aid in the war effort Following World War II the USGS expanded its international interests to include the Trust Terri-tories of the Pacific Islands and Antarctica

The USGS also played an important part in the

“Space Race” of the 1960’s Its geologists helped train Apollo astronauts for their lunar missions and

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vided technical expertise for the unmanned missions

to the planets Because of the demands created by the

nuclear arms race of the Cold War, the USGS

pro-vided scientific support to the Atomic Energy

Com-mission USGS scientists participated in the

evalua-tion of the effects of underground nuclear bomb

testing and the potential environmental effects from

the “peaceful” use of atomic energy

In 1983, President Ronald Reagan extended the

U.S exclusive economic zone to a distance of 200

nau-tical miles (370 naunau-tical kilometers) from the

coun-try’s shores, placing additional demands on the USGS

Reagan’s act more than doubled the area that the

USGS had to map and evaluate for its potential

min-eral and energy resources This information was

sig-nificant to U.S oil producers concerned with the

de-clining amounts of land-based sources of petroleum

The USGS also has been particularly involved with

natural disasters and their effects upon the

popula-tion Earthquakes, volcanic eruptions, and floods all

represent potential hazards to the American public,

and the USGS attempts to limit the loss of life

associ-ated with these natural disasters

Impact on Resource Use

The USGS employs about ten thousand scientists,

technicians, and support personnel Its headquarters

are in Reston, Virginia, and it has major offices in

Denver, Colorado, and Menlo Park,

California Incorporated within the

organization are four major

scien-tific disciplines: biology, geography,

geology, and hydrology The USGS

is charged with the classification of

public lands, the study of geologic

formations, and the assessment of

mineral resources In 2007, the USGS

developed a scientific strategy to

study climate variation, ecosystems,

natural hazards, and wild-animal

dis-eases

The USGS also continues to

mon-itor the nation’s natural resources

These responsibilities are assigned to

four major divisions The

Conserva-tion Division deals with all operaConserva-tions

involving prospecting for,

develop-ing, and extracting leasable

miner-als These minerals include coal, gas,

oil, oil shale, phosphate, potash, and

sodium compounds that are found on public lands They also include resources on the continental shelf The USGS also is involved in the determination of the production potential of these resources Modern un-derstanding of the formation and location of energy and mineral resource deposits is rooted in fundamen-tal scientific breakthroughs made by USGS scientists The Topographic Division prepares and maintains the topographic maps of the United States and its pos-sessions It also prepares national atlases and pro-duces various special-purpose maps that provide an analysis of natural resources The USGS is the primary civilian mapping agency in the United States, produc-ing the multipurpose 1:24,000-scale, 7.5-minute quad-rangle topographic maps These maps have been widely used to determine property locations in land transfer documentation and by backpackers, hikers, and many others for recreational activities Innovative ventures with the private sector have also given the world access to digital images of neighborhoods and communities in one of the largest datasets ever made available online

The Water Resources Division is responsible for de-termining the location, amount, quality, and availabil-ity of all water, both surface water and groundwater Flood control, pollution studies, and groundwater management are among many of its activities USGS scientists have pioneered advances in hydrologic

Clarence King (leaning against the tent pole), the president of the USGS, is flanked by his team of geologists in Utah in 1869 (Getty Images)

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niques for gauging the discharge in rivers and streams.

The USGS has established a stream-gauging network

of more than seventy-four hundred gauges to provide

“real-time” stream-flow data that is vital to flood

con-trol management USGS scientists have also

devel-oped models to represent the flow of complex

ground-water systems The use and management of ground

and surface water are among the most pressing

prob-lems USGS scientists face in the twenty-first century

The Geological Division conducts research in four

areas: environmental, economic, experimental, and

marine studies Its activities provide detailed

informa-tion on various minerals and informainforma-tion pertaining

to land use and conservation of natural resources

In-cluded within the activities of the Geological Division

is basic research that is directed toward a better

un-derstanding of the Earth as a whole The USGS

main-tains an Earthquake Hazards Program that monitors

earthquake activity worldwide through its National

Earthquake Information Center in Golden, Colorado

The agency also maintains a series of instruments

that monitor the 169 volcanoes scattered across the

United States and its territories and has developed

methods to help predict future eruptions The USGS

operates the National Geomagnetism Program that

monitors daily changes in the Earth’s magnetic field

Reaching far into space, the USGS also maintains

its Astrogeology Research Program that produces

maps of the Moon, Venus, Mars, and many of the

other moons in Earth’s solar system The National

Wildlife Health Center also is operated by the USGS

Its mission is to provide sound science and technical

support and to disseminate information to promote

science-based decisions affecting wildlife and

ecosys-tem health As an example, USGS biologists

devel-oped a revolutionary concept of wildlife resource

management They employed a sound scientific-based

approach that lets waterfowl conservation and recre-ational hunting work in tandem as adaptive manage-ment, not as conflicting interests As represented by its overall diversity, the USGS has evolved well beyond its original mission of mapping and minerals explora-tion

Paul P Sipiera

Further Reading

Parker, Philip M United States Geological Survey: Web-ster’s Timeline History, 1863-2007 San Diego, Calif.:

Icon Group International, 2009

U.S Geological Survey Bulletin: United States Geological Survey Washington D.C.: Author, 2009.

Worster, Donald A River Running West: The Life of John Wesley Powell New York: Oxford University Press,

2002

Web Sites U.S Geological Survey Geography

http://geography.usgs.gov/

U.S Geological Survey Minerals Information http://minerals.usgs.gov/minerals/

U.S Geological Survey Water Resources of the United States http://water.usgs.gov/

See also: Bureau of Land Management, U.S.; Coast and Geodetic Survey, U.S.; Department of the Inte-rior, U.S.; Erosion and erosion control; Floods and flood control; Groundwater; Mining wastes and mine reclamation; Oil and natural gas chemistry; Soil man-agement; Strip mining; United States

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Vanadium

Category: Mineral and other nonliving resources

Where Found

Vanadium minerals are found in the United States in

Arkansas, Colorado, Idaho, and Utah Major

interna-tional sources are China, Russia, and South Africa

Va-nadium is usually associated with igneous rocks and

often with other metals, such as lead, iron, chromium,

and uranium

Primary Uses

Vanadium combined with iron, called

ferrovana-dium, is used in making special steels valued for their

toughness, resistance to wear, and stability at high

temperatures Approximately 92 percent of U.S

con-sumption of vanadium is for alloying iron and steel, with the balance used in catalysts for chemical pro-duction

Technical Definition Vanadium (atomic number 23, chemical symbol V) is

a shiny metallic element with a density of 6 kilograms per liter (less than iron) that melts at 2,188 kelvin (higher than iron) It is malleable when pure but be-comes brittle in the presence of impurities, particu-larly carbon It is stable in air at room temperature but oxidizes above 920 kelvin There are isotopes of mass numbers 50 and 51 (V50and V51) of which the former

is weakly radioactive

Description, Distribution, and Forms Vanadium occurs in the Earth’s crust at an average concentration of 136 parts per million; it is the nine-teenth most abundant element Vanadium minerals include patronite (VS4), vanadinite (Pb5[VO4]3Cl), carnotite (K[UO2][VO4]), and more than sixty oth-ers Vanadates are sometimes found in phosphate rock or titaniferous magnetite Small amounts of va-nadium occur in petroleum, oil sands, oil shale, coal, and meteorites Certain sea creatures, such as sea squirts (ascidians), accumulate vanadium from seawa-ter, attaining concentrations ten million times higher

in their blood than are in the water Low levels of vana-dium are found in most plant and animal tissues, where its function is not always clear The average hu-man body contains about 1 milligram of vanadium

History Vanadium was first noticed by Andrés Manuel del Rio (1787-1849) in 1801 in Mexico Del Rio found evi-dence of an element he called erythronium in a lead ore (probably what would today be recognized as vanadinite) He later retracted his discovery based on consulting with chemists in France In 1830, Nils Ga-briel Sefström (1787-1895), a student of Jöns Jacob Berzelius (1779-1848), working in Sweden, isolated material from iron-making slag that he realized was the same as the erythronium reported by Del Rio He named the element vanadium after the Nordic

god-Steel & iron alloys 92%

Superalloys &

other alloys

6%

Other 2%

Source:

Historical Statistics for Mineral and Material Commodities in the United States

U.S Geological Survey, 2005, vanadium statistics, in

T D Kelly and G R Matos, comps.,

, U.S Geological Survey Data Series 140 Available

online at http://pubs.usgs.gov/ds/2005/140/.

U.S End Uses of Vanadium

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dess Vanadis Neither Sefström nor Del Rio succeeded

in isolating the pure metal Berzelius was the first to

describe the element’s properties in detail

Approxi-mately 70 percent pure metallic vanadium was

pre-pared by Henry E Roscoe (1833-1915) in 1867, but

purity approaching 100 percent was not achieved

un-til the twentieth century

Obtaining Vanadium

Preliminary treatment of ores involves crushing,

pul-verizing, and sifting, followed by flotation procedures

to eliminate unwanted silicates The ore concentrates

are then roasted in air with sodium carbonate to

yield sodium metavanadate The latter is converted to

vanadium pentoxide (V2O5) by acidification, using

sulfuric acid followed by strong heating Vanadium

pentoxide is the starting material for preparation of

other vanadium compounds, or of the metal itself

Heating the pentoxide to high temperature (1,223

kelvin) with calcium in the absence of air yields

metal-lic vanadium The metal may also be obtained by

reaction of trichloride with magnesium or (in small

amounts with high purity) by thermal decomposition

of the triiodide Ferrovanadium for steelmaking contains about 50 per-cent vanadium and is made by heat-ing the pentoxide with ferrosilicon and lime in an electric furnace The lime combines with the silicon to form slag

The United States imports 76 per-cent of its ferrovanadium from the Czech Republic Most of the U.S production of vanadium is from slag, petroleum combustion residues, fly ash, or recycled catalysts Carnotite, when processed for its uranium con-tent, yields vanadium as a by-product, but mining of other vanadium min-erals is uneconomical in the United States

Uses of Vanadium Vanadium is used in alloys for air-craft and for nuclear applications Vanadium compounds are also used

in ceramics and as catalysts in the production of maleic anhydride and sulfuric acid

Pure elemental vanadium is too expensive for any but the most critical applications One is the use of vanadium foil on steel to which tita-nium is to be bonded Pure vanadium is also used to make a superconducting alloy with gallium (V3Ga) for use in electromagnets This substance becomes super-conducting below 15 kelvin

Larger amounts of vanadium are used in special steels In these cases, the starting material is ferrova-nadium, which may contain up to 80 percent vana-dium (lower grades are available) Tool steels contain-ing vanadium, iron, and chromium are used for socket wrenches, pliers, and knife blades Vanadium content

of tool steels can be as high as 4 percent Smaller amounts of vanadium (a few tenths of a percent) are added to many steels to combine with carbon and ni-trogen and improve grain size Some of the beneficial effects of vanadium in steel result from vanadium car-bides, which may form spontaneously from the carbon

in steel or may be added as such Vanadium carbides are produced by heating sodium metavanadate with carbon in a vacuum furnace

Vanadium steel finds application in automobile parts such as axles, transmission parts, and springs,

A prospector stands adjacent to a vanadium shaft in Grand County, Utah, in this 1911

photograph (USGS)

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where it is valued for its light weight, toughness, and

resistance to wear The famous Model-T Ford of the

early twentieth century was advertised to contain

va-nadium steel parts In the military, vava-nadium steel is

used for armor and for soldiers’ helmets

In vanadium alloys, corrosion resistance combined

with strength is important for the pipes and tubes

used in boilers and chemical plants In nuclear

reac-tors, not only corrosion resistance but also the low

cross section of vanadium for the capture of thermal

neutrons is favorable An example is an alloy of 80

per-cent vanadium, 15 perper-cent chromium, and 5 perper-cent

titanium, which is suitable for fast breeder reactors

us-ing liquid sodium potassium alloy as coolant

Vanadium is also used in nonferrous materials,

par-ticularly aluminum and titanium alloys An alloy of 90

percent titanium, 4 percent aluminum, and 6 percent

vanadium is as strong as but lighter than steel and

suit-able for use in aircraft

Vanadium compounds are used in catalytic

appli-cations Probably the most important of these is in the

contact process for sulfuric acid manufacture, where

vanadium pentoxide is used to catalyze the reaction

of oxygen with sulfur dioxide Oxidation reactions

catalyzed by vanadium pentoxide include the

oxida-tion of naphthalene to phthalic anhydride and of

bu-tene to maleic anhydride Vanadium compounds such

as vanadium trichloride and vanadium oxytrichloride

are components, along with organoaluminum

com-pounds, of catalyst systems for manufacturing

vari-ous polyolefins, including ethylene propylene diene

type M (EDPM) synthetic rubber This product has

superior properties for automotive gaskets and hoses

and membranes under the shingles of the roof of a

building

Other applications of vanadium compounds

in-clude the use of vanadium salts to catalyze the

oxida-tion of aniline in manufacture of the dyestuff aniline

black and the use of vanadium pentoxide as a mordant

in dyeing Small amounts of vanadium pentoxide are

used in ceramic glazes and as an additive in glass to

re-duce transmission of ultraviolet light There is

inter-est in silver vanadium oxide as a cathode material in

lithium batteries with high energy densities

Vanadium may be an essential trace mineral in

nu-trition and is an ingredient of vitamin and mineral

supplements There is some evidence that vanadium

compounds are helpful in potentiating the effect of

insulin in the treatment of diabetes, but no specific

treatment has received government approval

Vana-dium compounds have also been shown to kill cancer cells, but again, no approved treatment is available There are health issues relating to vanadium In-dustrial exposure to vanadium-containing dust is a health hazard that may be encountered in milling or machining of vanadium alloys or in handling vana-dium chemicals such as vanavana-dium pentoxide Fly ash from combustion of coal and soot from combustion of heavy oil are sources of vanadium in the environment Eye and lung irritation and other problems can result from exposure

John R Phillips

Further Reading

Emsley, John Nature’s Building Blocks: An A-Z Guide to the Elements New York: Oxford University Press,

2001

Kaminski, Walter “Polyolefins.” In Handbook of Polymer Synthesis, edited by H R Kricheldorf et al 2d ed.

New York: Marcel Dekker, 2005

Lide, David R., ed CRC Handbook of Chemistry and Phys-ics 87th ed Boca Raton, Fla.: CRC Press, 2006 Polyak, Désirée E “Vanadium.” In Minerals Yearbook: Metals and Minerals 2007 Washington, D.C.: U.S.

Government Printing Office, 2009

Tracey, Alan S., Dail Ruth Willsky, and E Takeuchi Va-nadium: Chemistry, Biochemistry, Pharmacology and Practical Applications Boca Raton, Fla.: CRC Press,

2007

Wiberg, Egon, Nils Wiberg, and A F Holleman Inor-ganic Chemistry New York: Academic Press, 2001.

Woollery, M “Vanadium and Vanadium Alloys.” In

Kirk-Othmer Encyclopedia of Chemical Technology 5th

ed New York: John Wiley and Sons, 2007

Web Sites Natural Resources Canada Canadian Minerals Yearbook, 2001: Vanadium http://www.nrcan.gc.ca/smm-mms/busi-indu/cmy-amc/content/2001/65.pdf

U.S Geological Survey Mineral Information: Vanadium Statistics and Information

http://minerals.usgs.gov/minerals/pubs/

commodity/vanadium/

See also: Chromium; Gallium; Iron; Magnesium; Minerals, structure and physical properties of

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Categories: Countries; government and resources

Until the mid-1930’s, Venezuela’s principal export

was coffee, but the discovery and exploitation of oil—

which began in the early 1900’s but peaked later in

the century—changed the economic orientation of the

country Oil remains the principal product and

ex-port, and the nation consistently ranks among the top

ten exporters of oil in the global economy The country

is Latin America’s most important oil producer, but

economists warn that Venezuela is too dependent on

this sole commodity; as the price of oil goes up or down,

so does the nation’s economy.

The Country

Venezuela is a tropical country that sits along the

northern coast of South America The Caribbean

Sea and Atlantic Ocean demarcate its shoreline The

northern third of Venezuela consists of narrow coastal

lowlands, a branch of the Andes Mountains, and a

teardrop-shaped Lake Maracaibo Its midsection is

the expansive east-west grass-covered plains of the Orinoco River and its western tributaries The south-ern part of the country consists mostly of the ancient rocks of the Guiana Highlands Colombia, Brazil, and Guyana are to the west, south, and east, respectively Venezuela’s total area is roughly twice the size of Cali-fornia Venezuela is a mid-sized country for South America It is about one-tenth the size of Brazil (South American’s largest country) but ten times larger than French Guiana (the continent’s smallest country)

In 2008, Venezuela had the world’s thirty-third largest economy, but it is one of the world’s leading producers of crude oil The principal oil deposits are under the offshore Caribbean-Atlantic shelf, the Maracaibo basin, and the Orinoco plains This re-source accounts for about 90 percent of the total value

of the nation’s exports, and it gives the country a trade surplus annually The nation also exports iron, steel, and aluminum because of a juxtaposition of water power, iron ore, and bauxite in the Guiana Highlands Petroleum

Venezuela was the seventh-largest net oil exporter in

2007 The government nationalized its oil industry

An oil refinery in Morón, Venezuela The petroleum industry accounts for about 80 percent of the country’s exports (AFP/Getty Images)

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Global Resources Venezuela • 1293

Venezuela: Resources at a Glance

Official name: Bolivarian Republic of Venezuela Government: Federal republic

Capital city: Caracas Area: 352,170 mi2; 912,050 km2

Population (2009 est.): 26,814,843 Language: Spanish

Monetary unit: bolivar (VEF)

Economic summary:

GDP composition by sector (2008 est.): agriculture, 3.8%; industry, 37.6%; services, 58.6%

Natural resources: petroleum, natural gas, iron ore, gold, bauxite, other minerals, hydropower, diamonds

Land use (2005): arable land, 2.85%; permanent crops, 0.88%; other, 96.27%

Industries: petroleum, construction materials, food processing, textiles, iron ore mining, steel, aluminum, motor

vehicle assembly

Agricultural products: corn, sorghum, sugarcane, rice, bananas, vegetables, coffee, beef, pork, milk, eggs, fish

Exports (2008 est.): $93.54 billion

Commodities exported: petroleum, bauxite and aluminum, steel, chemicals, agricultural products, basic manufactures Imports (2008 est.): $48.1 billion

Commodities imported: raw materials, machinery and equipment, transport equipment, construction materials

Labor force (2008 est.): 12.59 million

Labor force by occupation (1997 est.): agriculture, 13%; industry, 23%; services, 64%

Energy resources:

Electricity production (2007 est.): 110.7 billion kWh

Electricity consumption (2006 est.): 83.84 billion kWh

Electricity exports (2006 est.): 542 million kWh

Electricity imports (2007 est.): 0 kWh

Natural gas production (2007 est.): 26.5 billion m3

Natural gas consumption (2007 est.): 26.5 billion m3

Natural gas exports (2007 est.): 0 m3

Natural gas imports (2007 est.): 0 m3

Natural gas proved reserves ( Jan 2008 est.): 4.708 trillion m3

Oil production (2007 est.): 2.667 million bbl/day Oil imports (2006 est.): 0 bbl/day

Oil proved reserves ( Jan 2008 est.): 78.27 billion bbl

Source: Data from The World Factbook 2009 Washington, D.C.: Central Intelligence Agency, 2009.

Notes: Data are the most recent tracked by the CIA Values are given in U.S dollars Abbreviations: bbl/day = barrels per day;

GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles.

Caracas

Venezuela

Brazil

Trinidad

y Tobago

C a r i b b e a n S e a

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in 1975-1976, creating Petróleos de Venezuela S.A.

(PDVSA), the country’s state-run oil and natural gas

company PDVSA accounts for about 50 percent of

the government’s revenue and about 80 percent of

nation’s export earnings The company has lucrative

contracts with foreign companies that drill for the

country’s oil and natural gas PDVSA refines about

one-third of the crude oil and all the natural gas that

these ventures produce The remaining crude oil is

shipped to other countries (mainly to the United

States) for refining CITGO, a familiar company name

in the United States, is a wholly owned subsidiary of

PDVSA that has about fourteen thousand branded

retail outlets (both directly owned and affiliates) in

the United States

Oil production in Venezuela comes from four

ma-jor sedimentary basins: Maracaibo, Falcón, Apure,

and Oriental The latter three basins make up the

so-called “Orinoco Belt,” which runs east-west across the

middle of the country in the Orinoco plains region

The Maracaibo basin supplies slightly less than

one-half of Venezuela’s oil production The increasing

depth of remaining oil in this basin requires heavy

in-vestment to maintain current capacity For example,

in order to lessen an ongoing decline in withdrawal

rates, oil drillers reinject natural gas into the oil

reser-voirs in order to increase pressure in the deeper wells

The Orinoco Belt has crude oil that is extra heavy

and requires unconventional extraction and refining

methods Refineries along the U.S Gulf coast are

spe-cifically designed to handle the heavy crude varieties;

consequently, that region is the largest recipient of

the Orinoco crude exports Besides the United States,

other important destinations of Venezuelan

petro-leum include South America, Europe, and the

Carib-bean (especially Cuba) Much of the crude oil that is

exported to the Caribbean is refined there and

re-exported as petroleum products to other locations

Industry experts calculate production was 2.7

mil-lion barrels of oil per day in 2007, but the production

could be higher, because unexploited recoverable

re-serves in the Orinoco Belt range from 100 to 270

bil-lion barrels Venezuela’s oil production has fallen, but

PDVSA has planned to develop the Orinoco Belt

re-serves aggressively The most notable companies

drill-ing in this region—such as Conoco-Philips, Chevron

Texaco, and Exxon-Mobil—were American until 2008

and 2009, when PDVSA signed contracts with oil

com-panies from India, Japan, Russia, Iran, and China to

exploit the heavy Orinoco crude

Natural Gas Venezuela does not export natural gas to the global economy, a fact that is likely to change in the future The nation had 4.7 trillion cubic meters of proven natural gas reserves in 2008; in the Western Hemi-sphere, only Canada had more reserves About 90 per-cent of Venezuela’s natural gas production occurs in association with oil reserves As a result, the petro-leum industry consumes more than 70 percent of Venezuela’s natural gas production, with the largest share of that consumption in the form of reinjection

to aid crude oil extraction PDVSA produces the larg-est amount of natural gas in the country, because there is limited participation of privately owned Vene-zuelan companies in the sector However, since the late 1990’s, the government has permitted foreign private companies to explore for new reserves in the Orinoco River delta region and off the northeast coast The exploratory work has proved that the natu-ral gas reserves in both areas are commercially viable The offshore reserves straddle the maritime bound-ary between Venezuela and Trinidad and Tobago The two countries reached an accord spliting the mar-itime reserves in 2007; 75 percent of the production will go to Venezuela

As of 2009, Venezuela planned to build liquefied natural gas (LNG) plants that convert natural gas, which is predominantly methane (CH4), to liquid form for ease of storage and exporting In 2008, Venezuela signed agreements to create three joint venture com-panies to build the plants along the northern coast of the country PDVSA planned to use the plants to liq-uefy the gas piped from offshore gas-drilling plat-forms In 2009, PDVSA announced the signing of

a multibillion-dollar joint venture with Portuguese, Argentine, U.S., and Japanese firms to develop the massive offshore natural gas fields According to the agreement, PDVSA will have a majority stake in the venture and will construct and operate two liquefac-tion plants at the Gran Mariscal de Ayacucho indus-trial complex The company will also construct pipe-lines to transport the fuel from the gas fields to the LNG facilities The state-run PDVSA is expected to begin exporting this resource to South America, Eu-rope, the Caribbean, and Asia by 2013 or 2014 Water Power

Hydroelectricity is electrical power that dammed stream water generates when it is released through turbines It is a renewable form of energy and

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fore relatively cheap to produce compared to energy

derived from fossil fuels Venezuela ranks ninth in

per-capita production of hydroelectricity among the

149 nations that produce it Hydroelectric energy

sup-plies 25 percent of the country’s energy needs

(com-pared to 5.6 percent in the United States) The

na-tion’s hydroelectricity comes from dams built on the

rivers of the Guiana Highlands, especially the Caroní

River, which has four dams The government planned

to build two more dams on that river The Guri Dam,

which is just above the mouth of the Caroní, began

op-erations in 1978 and has the third largest generating

capacity among hydroelectric dams in the world The

Three Gorges Dam in China and the Itapúa Dam on

the border of Brazil and Paraguay are first and second

in generating capacity, respectively

Water power is important to Venezuela’s

participa-tion in the global economy in three ways First, the

us-age of water power rather than oil to produce energy

allows the country to sell more of its oil to other

na-tions Second, Venezuela generates more

hydroelec-tricity than it consumes, so it earns extra income by

exporting surplus hydroelectricity to neighboring

Co-lombia and Brazil Third, and most important from

an economic standpoint, Venezuela is able to use

low-cost hydroelectricity to produce and export large

amounts of iron, steel, and aluminum to the global

market In value terms, iron and steel exports rank

second and aluminum ranks third in Venezuela’s

overseas economy

Iron Ore

Venezuela’s iron-ore deposits are in the Guiana

High-lands, which rise behind the city of Ciudad Guayana,

the industrial heart of the country The fast-flowing

Caroní River descends from the mountains to

gener-ate the electricity that powers the iron and steel mills

of the city The city, which is near the juncture of

the Caroní and Orinoco rivers, is one of Venezuela’s

fastest-growing urban centers Demographers expect

that Ciudad Guayana will reach two million people by

2030 The city’s growing economy and Venezuela’s

steel production would not be possible without the

juxtaposition of iron ore and the Guiana Highland’s

fast-flowing rivers

The mining of iron ore for steel production

domi-nates the economy of the Guiana Highlands In the

vastness of the mountains lie huge deposits of iron ore

and bauxite (the raw material for aluminum) The

re-gion also has deposits of gold, silver, uranium, nickel,

and phosphates, but iron ore is the most abundant and valuable ore of the region Bauxite ranks second

in value After World War II, the great iron-ore depos-its on the northern rim of the plateau attracted the former giants of the U.S steel industry—the U.S Steel and Bethlehem Steel corporations—to the re-gion Both companies had large open-pit mines The main U.S Steel mine covered the entire top of the mountain Cerro Bolívar Bethlehem Steel’s main mine was nearby at the town of El Piar These companies mined the ore and shipped it a short distance by rail to barges waiting on the Orinoco River The barges took the ore to the Paria Peninsula, just beyond the mouth

of the Orinoco There, the ore was loaded on ocean-going carriers for export to the United States The Venezuelan government took over the iron-mining operations in 1975 It now controls all aspects

of iron-ore mining and steel production through the mining conglomerate CVG Ferrominera Orinoco The company controls the extracting, processing, transporting, and marketing of the iron ore and its products Its headquarters are in Puerto Ordaz Rather than exporting the iron ore as the U.S companies did, Ferrominera processes it into iron and steel at its plants at Ciudad Guayana The largest market for Ven-ezuelan steel is the domestic oil industry PDVSA needs structural steel and iron and steel pipes Never-theless, iron-ore products—iron, iron pellets and in-gots, and flat-rolled sheets of iron and steel—rank second (behind petroleum) in value among the coun-try’s global exports Venezuela was thirteenth in pro-duction of iron ore in 2008

Bauxite Venezuela has one of the world’s largest supplies of bauxite, the ore for making aluminum Like iron ore, bauxite is in the country’s enormous Guiana High-lands region The bauxite is a residual rock that formed as a result of laterization of Tertiary sediments that lay horizontally and unconformably on the Pre-cambrian basement rocks of the highlands Except for the dissected topography, the bauxite is relatively accessible in two horizontal layers about 4 to 10 me-ters below the summit surfaces

The bauxite ore consists of one or more aluminum hydroxide minerals plus various mixtures of alumina-silicates (such as clay), iron oxide, silica, titanium, and other impurities in trace amounts Processing alumina starts with separating it from ore by means of

a wet chemical caustic leach process Next, the

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