Ch 3 3 sedimentary rocks

Igneous rocks that crystallize from magma and are composed almost entirely of quartz and feldspars have an ____.. Weathering, Erosion, and Deposition• Weathering is any process which bre

Warm Up 10/4

1 The igneous rock texture that is characterized by two distinctly different crystal sizes is called

a porphyritic texture c fine-grained texture

b glassy texture d coarse-grained texture

2 Igneous rocks that crystallize from magma and are composed almost entirely of quartz and feldspars have a(n)

a andesitic composition c ultramafic composition

b basaltic composition d granitic composition

3 A rock that forms when magma hardens beneath Earth’s

surface is called an

a intrusive metamorphic rock

b extrusive igneous rock

c intrusive igneous rock

Sedimentary Rocks

Chapter 3, Section 3

Weathering, Erosion, and Deposition

• Weathering is any process which breaks rocks

into sediments

• Erosion involves weathering and the removal of

rock When an agent of erosion – water, wind,

or gravity – loses energy, it drops the

sediments This process is called deposition.

• Sediments are deposited according to size.

• Smaller sediments will travel longer distances

Weathering, Erosion, and

Deposition

Compaction and Cementation

• Compaction and cementation change

sediments into sedimentary rocks

• Compaction is a process that squeezes,

or compacts, sediments

• Compaction is caused by the weight of

sediments

• Cementation takes place when dissolved

minerals are deposited in the tiny spaces among the sediments.

Compaction and Cementation

Concept Check

• What are the five major processes

involved in the formation of sedimentary rocks?

• Weathering, erosion, deposition,

compaction, and cementation

Classification of Sedimentary

Rocks

• Just like igneous rocks, sedimentary rocks can be classified into two main groups

according to the way they form.

• Clastic Sedimentary Rocks – rocks that

are made of the weathered bits of rocks

and minerals

when dissolved minerals precipitate from water solutions

Clastic vs Chemical Sedimentary

Rocks

Chemical Sedimentary Rocks

Formation of

Coal

Concept Check

• What are the major types of clastic

sedimentary rocks?

• Conglomerates and breccia, sandstone,

shale and siltstone

Sedimentary Rock Features

are a clue to how, when, and where the rocks formed.

period of sedimentation

the youngest layers are found at the top

rocks; they can answer questions as to where

Sedimentary Rock Features

• Read Chapter 3, Section 3 (pg 75-79)

• Do Section 3.3 Assessment #1-9 (pg 79)

• Print out “Exploration Lab 3 – Rock

Identification” for next class!