Describe The Characteristics Of Metamorphic Rocks A Metamorphic

Describe The Characteristics Of Metamorphic Rocks A. Metamorphic Rocks 1. Meta = change Morph = form

2. A metamorphic rock is any rock that changes its form due to HIGH heat and pressure. 3. these changes include: n q q q a. increased density b. recrystallization of minerals 4. conditions of high heat and pressure exist deep within the Earth, during volcanic activity and during mountain building.

B. There are two main forms of metamorphism: n 1. regional q q q a. occurs over large areas b. particularly in areas of mountain building and plates colliding. c. due to the movement of Earth’s crust.

Foliation is a term used to describe metamorphic rocks

2. Contact metamorphism n n a. any rock that comes into contact with molten material will be metamorphosed. b. “teeth” marks are used to represent the area of contact metamorphism.

c. Contact metamorphism can be either: n 1. intrusive q Molten material does not break the surface; however, the rock material under the surface in contact with this material is metamorphosed.

n 2. extrusive q Molten material breaks the surface (volcanic eruption) and rocks coming into contact with this material are metamorphosed.

C. How do we recognize a metamorphic rock? n n n 1. a distortion of structure OR 2. banding or zoning 3. a rock with NEW composition has formed. 4. there is a recrystallization of minerals. 5. the original density has increased.