Earth’s Interior

Crust OOOOutermost layer of solid rock that includes both dry land and ocean floor 5555-70 kilometers thick TTTTwo Types Oceanic Crust - made of mostly basalt- Thinnest Crust - 7 km avg Continental Crust - made of mostly granite- Thickets crust - 35 km avg

Mantle MMMMade of very hot, but solid rock AAAAbout 3000 kilometers thick MMMMoho - the boundary between the mantle and the crust LLLLithosphere - crust & upper mantle AAAAsthenosphere - soft layer of mantle, like road tar LLLLower mantle - solid, hot rock

The mantle exhibits plasticity, where molten rock bends and flows

Convections currents exist in the mantle.

Cooler, denser mantle material sinks toward the core and warmer, less dense mantle material rises toward the crust.

Outer Core  Molten, liquid metal

Inner Core  Dense ball of solid metal

 STRESS

As rocks undergo STRESS, the DEFORM SSSStress - the forces that push and pull on the Earth’s crust DDDDeformation - an change in the original shape or volume of rocks

Types of Stresses CCCCompression - type of stress that squeezes rocks together TTTTension - type of stress that pulls rocks apart SSSShearing - type of stress that pushes rocks in two opposite horizontal directions

STRESS can cause rocks to FRACTURE  Fracture - break or crack in rocks

STRESS can also cause FAULTS  FAULT - a break or crack along which rocks move

Faults HHHHanging Wall - the block of rock above a fault. Longer at the top FFFFoot Wall - the block of rock below a fault. Longer at the bottom

Types of Faults NNNNormal Fault - a fault in which the hanging wall moves down relative to the foot wall

 Reverse Fault - a fault in which the foot wall moves down relative to the hanging wall

Example - Thrust Fault - a reverse fault in which the hanging wall slides over the foot wall Example - Thrust Fault - a reverse fault in which the hanging wall slides over the foot wall

 Lateral (Strike slip) fault - a fault along which the rocks move horizontally past each other

Fault block mountain  A mountain formed by blocks of rocks uplifted from normal faults

Rift Valley  A valley formed when the block of land between two normal faults slides downward.

STRESS can also cause FOLDING  FOLD - a bend in rock

Types of Folds  Anticline - an upward fold in rocks  Syncline - an downward fold in rocks

The 4 factors that determine whether a rock will fault or fold: TTTTemperature PPPPressure RRRRock type HHHHow the stress is applied

Geographic Features PPPPlateau - a large area of flat land that is raised high above sea level and consists of horizontal rock layers

 Domes - a raised area shaped like the top of a sphere often formed by magma pushing rock layers upward.