ES Unit 2 Quizlet

tension

stress that occurs when forces act to stretch an object

rift valley

A deep valley that forms where two plates move apart

Offset spreading

A feature associated with a transform fault that may occur in the portion of a fracture zone

Define geothermometer and give two examples.

A geothermometer is a metamorphic rock that defines a minimum temperature a rock must be in order to become metamorphic. (Examples: Staurolite and Hornblende)

Igneous Rock

formed from cooling magma

divergent plate boundary

Boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them

transform plate boundary

Boundary between two plates that are sliding past each other.

Plate boundary type and info: Divergent

Features found at boundary: Fault block mtns, rift valleys, mid ocean ridge Type of stress: Tension Type of fault: Normal Types of rock found here: Igneous/ contact metamorphic

Plate boundary type and info: Convergent

Features found at boundary: Ocean trench, Folded mtns, volcanoes Type of stress: Compression Type of fault: Reverse Types of rock found here: Igneous, Contact and Regional Metamorphic

Plate boundary type and info: Transform

Features found at boundary: Offset Geology Type of stress: Shear Type of fault: Strike Slip Types of rock found here: Both Igneous and Metamorphic

Convergent

Metamorphism is most common at this boundary

Label the letters of the rock cycle correctly:

Sedimentary Igneous Metamorphic

compression stress

Stress that squeezes rock until it folds or breaks

Define Contact Metamorphism:

This type of metamorphism can be at a plate boundary but not always. This happens when there is rock exposed near magma, usually near the surface.

Define Regional Metamorphism:

This type of metamorphism happens at convergent boundaries and produces foliated textures.

The faults in the NW corner of Georgia show mountain formation.

What type of boundary formed these mountains? An old convergent plate boundary If the faulting was because of divergent boundaries, what type of landform would be created? (hint: happens in East Africa) Rift valley or Fault block mountains

folded mountains

When rock layers are squeezed together and pushed upward.

convergent plate boundary

A tectonic plate boundary where two plates collide, come together, or crash into each other.

Metamorphic Rock

A type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions.

Compare the age of the Appalachian Mountains to the Himalayas. Which is older/younger and How do we know?

Appalachian= About 500 million years old, Himalayan= About 40 million years old. We know because of weathering and erosion rates.

5. What are the two variables needed to increase the metamorphic grade of a rock? (example: Phyllite few visible crystals, but gneiss has many. Why?)

As heat an pressure increase, metamorphic grade increases. Phyllite forms at a lower metamorphic grade (less heat and pressure)

What type of plate boundary would you most likely find minerals and deposits?

Convergent boundaries, manganese nodules at Divergent boundaries

Where do we find Mafic minerals?

Oceanic Crust

Convergent boundary

Ore deposits such as gold can be found at this boundary

Sedimentary Rock

a rock that forms from compressed or cemented layers of sediment