Plate boundary movement

Folds/folding

Folds are bends in rock that form when compression shortens and thickens part of Earth's crust. The collisions of two plates can cause compression and folding of the crest.

Plateaus

Forces that raise mountains can also raise plateaus. A plateau is a large area of flatland elevated high above sea level.

Mountain formation

The forces of plate movement can build up earth's surface. Over millions of years, fault movement can change a flat plane into a towering mountain range.

Convergent boundary

The place where two plates come together, or converge.

Divergent boundary

The place where two plates move apart, or diverge. Most of these occur at the mid Ocean Ridge. Divergent boundaries can also occur on land. A deep valley called a rift valley forms along the divergent boundary.

Tension

The stress force that pulls on the crust, stretching rock so that it becomes thinner in the middle.

Reverse faults

Compression forces produce reverse faults. A reverse fault has the same structure as a normal fault, but the blocks move in opposite directions.

Fault-block mountain

When normal faults uplift a block of rock, a fault block mountains forms.

Plate Boundary types (3)

1. Convergent 2. Divergent 3. Transform

Fault types (3)

1. Normal 2. Reverse 3. Strike-slip

Stress types (3)

1. Shearing 2. Tension 3. Compression

Anticline

A fold and rock that bends upward into an arch.

Syncline

A fold in rock that bends downward in the middle to form a bowl.

Transform boundary

A place where two plates slipped past each other, moving in opposite directions. Earthquakes occur frequently along these boundaries.

Strike-slip fault

Shearing creates strike slip fault. Any strike slip fault, the rocks on either side of the fault slip past each other sideways with little up or down motion.strike slip fault that forms the boundary between two plates is called a transform boundary. The San Andreas Fault in California is an example of a strike slip fault that is a transform boundary.

Compression

Stress force that squeezes rock until it folds or breaks.

Shearing

Stress that pushes a mass of rock into opposite directions.

Normal faults

Tension forces in Earth's crust cause normal faults. In a normal fault, the fault is at an angle, so one block of rock lies above the fault well the other block lies below the fault.