Which type of igneous rock forms on the surface of Earth from lava? Intrusive OR Extrusive.

Bell Ringer 1/11/16

Which type of igneous rock forms on the surface of Earth from lava?

Intrusive OR Extrusive

METAMORPHIC ROCKS

Metamorphic rocks form from other rocks due to intense heat and pressure***. There can be NO melting!

Metamorphic rocks are from recrystallization of unmelted material over a long period of time. This forms larger, denser crystals.

Two types of metamorphism

1. Regional – formed by forces acting over large areas, at great depth where extreme temperature*** and pressure exist. High Pressure: caused by collisions of plates A great region to find metamorphic rock is in

mountains!

Regional metamorphism Foliation: reorientation of mineral grains

Banding: concentration of minerals into zones of light and dark colors

Two types of metamorphism

2. Contact – occurs at regions where magma comes into contact with pre-existing rock.

High temperature changes the rock without melting

Textures of metamorphic rocks

1. Foliated Examples: Slate, Gneiss, Schist, Phyllite

2. Non-Foliated Examples: Hornfels, Marble, Quartzite

Identification of metamorphic rocks

1. Check for foliation2. Check for grain size3. Check composition4. Use ESRT (page 7)

Examples of metamorphic rocks and their parent material

1. Marble – metamorphic form of limestone

Examples of metamorphic rocks and their parent material:

2. Quartzite – from sandstone

Examples of metamorphic rocks and their parent material:

3. Slate – usually from metamorphism of shale

Examples of metamorphic rocks and their parent material:

Phyllite – further metamorphism of slate

Examples of metamorphic rocks and their parent material:

Schist – foliated – contains layering, is easily broken

Examples of metamorphic rocks and their parent material:

6. Gneiss – highly distorted – contains banding

Usually from granite

Science Review Game- Mixed Rock