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