how does the u.s. geological survey define earthquakes?

Answer 1

The technical term is "All Hell Breaks Loose".

Answer 2

They're these seismic tremors in the Earth's crust when two tectonic plates rub against each other. They can travel very far and destroy lots of stuff on the surface, and even drag whole counties underground in subduction zones. California sits on an area filled with fault lines which tend to shift and rumble occasionally; hopefully they are releasing the pent up geological energies slowly over time so the whole state doesn't rip off and slide into the Pacific someday.

Answer 3

An earthquake is a trembling or a shaking movement of the Earth's surface. Earthquakes typically result from the movement of faults, quasi-planar zones of deformation within its uppermost layers. The word earthquake is also widely used to indicate the source region itself. The solid earth is in slow but constant motion (see plate tectonics) and earthquakes occur where the resulting stress exceeds the capacity of Earth materials to support it.

Answer 4

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