Rock Cycle• Magma- Molten rock below the

surface of the Earth• Lava- Molten rock above the Earth’s

surface• Crystallization- When magma cools

and forms igneous rock

Rock Cycle• Weathering-

When rock is broken down into smaller particles– Forms small

particles called sediment

Rock Cycle• Lithification- Conversion into

rock from sediment

• Metamorphism- Conversion of sedimentary rock to metamorphic rock through heat and pressure

Rock cycle• Melting- Conversion of rock

back into magma

Rock Cycle

Types of Rock• Igneous rock- Rock formed directly

from cooling magma–Extrusive rock- Rock formed outside

of the surface of the Earth- Basalt

–Intrusive rock- Formed within the Earth- Granite

Classifying Igneous Rock

• Texture- Size and arrangement of crystals–Slow cooling rock- Larger crystals

–Fast cooling rock- Smaller crystals

Classifying Igneous Rock

–Coarse grained texture- Intergrown crystals of equal size

• Granite

–Porphyritic texture- Large crystals imbedded in smaller crystals

Classifying Igneous Rock

• Glassy- Smooth, even texture similar to glass–Obsidian

Mineral composition

• Different minerals crystallize at different temperatures and will form rocks with varying mineral composition

Bowen Reaction Series

• Outlines the order of crystallization of different minerals in the magma of the Earth

Naming Igneous Rocks

• Igneous rocks are named for the texture and mineral composition of the rock

Sedimentary Rocks

• Sediments are turned to rock by compaction and cementation

Sedimentary Rock• Erosion- When natural forces

loosen and carry away fragments of rocks

• Deposition- When sediment settles out of water or wind to form a layer of sediment

Sedimentary Rock• Compaction- Particles moving

closer together by the weight of other sediment on top

• Cementation- “gluing” of sediment by minerals deposited by ground water

Types of Sedimentary Rock

• Detrital/ Clastic- Rock formed from solid particles of weathered rock

• Chemical - Precipitates of chemically eroded sediment

• Organic- Sedimentary rock made up of once living things

Detrital Sedimentary Rock • Made of various size particle

–Geologists use sediment size when classifying detrital sedimentary rock

Detrital Sedimentary Rock• Boulder> 256 mm• Cobble= 64-256 mm• Pebble= 4-64 mm• granule= 2-4 mm• Sand = 1/16-2 mm• Silt= 1/256 - 1/16• Clay= 1/256

Chemical Sedimentary Rock

• When substances dissolved in water are deposited through evaporation, precipitation, or chemical conversion from substance to another

Chemical Sedimentary Rock

• Evaporites- Rock deposited by evaporation- Salt–Rock Salt is used to make glass, paper,

soap and dairy products• Heat and pressure- Organic matter

that is transformed- Coal

Organic • Coal- Rock made from

compressed and heated plant an animal material

• Limestone- Rock made from shells of once living organisms

Coal Formation• Peat- partially altered plant material- Low

energy• Lignite- Soft brown coal- Moderate

energy• Bituminous coal- Soft black coal- High

energy• Anthracite- Hard, black coal- High

energy

Features of Sediment

• Deposited in strata or beds- Layers of rock laid down at separate times and lithified into rock

Features of Sedimentary Rock

• Contain fossils of ancient organisms• Contain records of the types of life,

climate, and conditions in an area at certain times in history

Types of sedimentary rock

• Sandstone- Compressed sand• Shale- Compressed swamp or bog organic

material• Conglomerate- Rock formed from stream

bed material• Coquina- Formed from shell material near

the ocean

Coral Reefs• Skeletons of coral that build up to

form a reef in shallow warm seas.

• Skeletons build up on one another as corals die and other corals build on top of them.

Coral Reefs• Atoll- A ring shaped coral

reef that forms around a volcanic island far from land.

Limestone from coral reefs

• As coral reefs build the old coral becomes limestone which over millions of years uplift to form continental limestone

Metamorphic Rock

• Rock that has been changed as a result of heat and pressure from one rock form to another

Metamorphic Rock

• Can be derived from igneous, sedimentary, or other metamorphic rock

Metamorphism• Low grade- Slight changes occur

in the rock

• High grade- Massive changes occur

Types of Metamorphism

• Regional metamorphism- Occurs over a large area during mountain building or other High energy situation

Types of Metamorphism

• Contact metamorphism- When rock comes in contact with magma and is sub sequentially changed into another form.

Classifying metamorphic rock

• Foliated- Fine grained, cleaves easily- Slate–Schists- Strongly foliated–Gneiss- Banded foliated rock

Classifying metamorphic rock• Nonfoliated Rock- Interlocking

crystals–Marble- Metamorphosis of

limestone –Quartzite- Metamorphosis of

quartz crystals