Post on 02-Jan-2016
A. Igneous Rock
-Forms when _______, _______, _________ crystallizes (cools and solidifies).
Magma forms 3 ways:1. _________________2. _________________3. _________________
Basalt lava (glowing rock) oozes over basalt lava flow
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Felsic Rock-___________________-made of aluminum, potassium, silicon, and sodium.
Mafic Rock-__________________-Made of calcium, iron, and magnesium.
Course-grained Fine-grained
Course-grained Fine-grained
a. Composition of Igneous Rock
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!1. What size crystal forms from extrusive rock?2. What is one way magma forms?3. 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:?
Rock ID practiceUse 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
Sedimentary RockStrata layers of rock.
Stratification The process in which sedimentary rocks are arranged in layers.
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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.
Regional Metamorphism
-Pressure builds up in rock that is buried deep below rock formations or when large pieces of rock collide.
• Contact Metamorphism– Rock undergoes
metamorphism when it comes in contact with magma or is heated by nearby magma.
Origins of Metamorphic RockOrigins of Metamorphic Rock
Textures of Metamorphic Rock
Foliated the texture of metamorphic rock in which the mineral grains are arranged in planes or bands.