Types of Rocks

3 Major (Geologic) Rock Groups Igneous Rock Sedimentary Rock Metamorphic Rock

Identifying Rocks Igneous pattern Metamorphic pattern Sedimentary pattern

Basalt lava (glowing rock) oozes over basalt lava flow A. Igneous Rock -Forms when _______, _______, _________ crystallizes (cools and solidifies). Magma forms 3 ways: _________________ Holt Online Visual: Comparing Int. & Ext Igneous Rocks Basalt lava (glowing rock) oozes over basalt lava flow

Intrusive Igneous Rock -Forms _________ Earth -_______________________

b. Extrusive Igneous Rock -Forms on _________________ of Earth -___________________________

a. Composition of Igneous Rock Felsic Rock -___________________ -made of aluminum, potassium, silicon, and sodium. Mafic Rock -__________________ -Made of calcium, iron, and magnesium. Fine-grained Course-grained Course-grained Fine-grained

b. Texture of Igneous Rock -________ cooling forms ________crystals. (Coarse-grained Texture) -_________ cooling forms ________ crystals. (Fine-grained Texture)

-Rate of cooling influences crystal size. Fast cooling = small crystals Slow cooling = large crystals Show Holt Visual: Igneous Rock Texture

Pop Quiz! What size crystal forms from extrusive rock? What is one way magma forms? Generally speaking what color are felsic rocks? 4. Quality of rock based on the size, shape, and arrangement of grains is referred to as… 5. What are the 2 characteristics that geologist study to identify rock:?

Igneous Rocks Rock ID practice Use the rock key to identify the various rocks on your table: Igneous Rocks Classified according to composition & texture Glassy- shiny and look like glass, not organized into crystals. Ex: obsidian

Fine-grained-made of interlocking crystals. Ex: basalt BASALT

More Igneous Rocks… Course Grained Texture- Granite

More Igneous Rocks… Porous- no crystals, cools rapidly, looks like a sponge. Ex: pumice

More Igneous Rocks… Diffferent size crystals locked together

More Igneous Rocks…

Sedimentary Rock Strata layers of rock. Stratification The process in which sedimentary rocks are arranged in layers. Holt Visual Sedimentary Rock Cycle

3 Types of Sedimentary Rock 1. Clastic forms when rock or mineral fragments are cemented together.

2. Chemical forms when minerals crystallize out of solution, such as sea water, to become rock.

3. Organic forms from the remains of once-living plants and animals. Ex: Limestone Coal Chalk

Metamorphic Rock -Rocks that have undergone a change in texture, structure, or composition. -Changes in heat and pressure cause rocks to change from one form to another.

Origins of Metamorphic Rock

Regional Metamorphism Contact Metamorphism Rock undergoes metamorphism when it comes in contact with magma or is heated by nearby magma. Regional Metamorphism -Pressure builds up in rock that is buried deep below rock formations or when large pieces of rock collide. Origins of Metamorphic Rock

Textures of Metamorphic Rock Foliated the texture of metamorphic rock in which the mineral grains are arranged in planes or bands.

Nonfoliated -The texture of metamorphic rock in which the mineral grains are not arranged in planes or bands.