AIM: How are metamorphic rocks formed, classified and used?

OBJ: Given notes and activity sheet SWBAT explain how metamorphic rocks are formed, classified and used with 70% accuracy

DN: HW Check- WEDS Activity Sheet (distribute Answer Key); Watch video https://www.youtube.com/watch?v=kRUwchlza88

ACT: Introduction to Metamorphic Rocks (Notes)Text, read p. 160-162; Complete Metamorphic Rocks Activity Sheet

HW: Complete Metamorphic Rocks Activity Sheet; Minerals & Rocks Exam, March 20.

Metamorphic RocksMetamorphic = change form; heat & pressure deep beneath Earth’s surface can change any rock into a metamorphic rock.

Metamorphism occurs:

1) At the site of plate collision (subduction)

2) Within the core of mountains

3) Near rising magma plumes.

Types of Metamorphic RocksHigh Temperature: changes the size & shape of the grains or mineral crystals (= recrystallization).Extreme Pressure: squeezes rock so tightly that mineral grains /crystals line up in flat, parallel layers.

Metamorphic RocksMetamorphic Rocks are classified based on the arrangement of the grains (crystals):

Foliated Rocks: the crystals are arranged in parallel layers or bands.

Nonfoliated Rocks: the mineral grains are arranged randomly and grain (crystal) size has increased (= recrystallization). These rocks are extremely hard.

original rock → metamorphic rock

shale → slate

granite → gneiss

sandstone → quartzite

limestone → marble

Granite Metamorphism Gneiss

Limestone Metamorphism Marble

Shale Metamorphism Slate

Limestone Metamorphism Marble

High Grade

Metamorphic Settings

Uses of Metamorphic RockBuilding: slate flooring, walkways, chalkboard, marble

Sculpture: marble Lincoln Memorial