Theory that Earth's crust is divided into plates & the plates move around on the mantle

Theory that magma rises to surface at mid-ocean ridge & cools to form new seafloor

Boundary between two plates moving toward each other

Shaking of the ground caused by sudden movement of large blocks of rocks along a fault

In an earthquake, the point underground where the rocks first begin to move

These waves move along Earth's surface & cause the most damage

The point on Earth's surface directly above the focus of an earthquake

Fastest seismic waves, first to reach a location after an earthquake, also called P waves

Small, steep-sided volcanoes made of loosely packed layers of tephra, very explosive eruptions

Boundary between 2 plates that are sliding past one another

In these faults, blocks of rock move sideways on either side of the fault plane

Volcanoes having alternate layers of lava & tephra, have repeated explosive & non-explosive eruptions

In these faults, the block of rock above the fault plane slides down relative to the other block

Along these faults, the block of rock above the fault plane moves up relative to the other block

The 2nd seismic waves to arrive at any particular location after an earthquake, also called S waves

Boundary between 2 plates that are moving apart