A Violent Pulse: Earthquakes

Flashcards covering key terminology and concepts related to earthquakes, their causes, types, measurements, and effects.

Earthquake

A seismic event caused by the rapid release of energy in the Earth's crust, resulting in ground shaking.

Hypocenter

The location within the Earth where fault slip occurs, usually on a fault surface.

Epicenter

The land surface location directly above the hypocenter.

Normal Fault

A fault where the hanging wall moves down relative to the footwall due to extensional forces.

Reverse Fault

A fault where the hanging wall moves up relative to the footwall due to compressional forces.

Thrust Fault

A type of reverse fault with a low angle of slope, common in compressional mountain belts.

Strike-Slip Fault

A fault where one block slides laterally past another without vertical movement.

Seismic Waves

Waves of energy that travel through the Earth and are generated by earthquakes.

P-waves

Primary waves that compress and expand material in the direction of wave travel, fastest seismic waves.

S-waves

Secondary waves that move material back and forth perpendicular to the direction of wave travel.

L-waves

Surface waves that travel along the Earth's exterior and are the slowest and most destructive seismic waves.

Seismograph

An instrument that records ground motion during an earthquake.

Magnitude

A measure of the energy released by an earthquake, often quantified using various scales.

Mercalli Scale

A scale measuring the intensity of an earthquake based on observed effects and damage.

Liquefaction

A phenomenon where saturated soil loses strength due to shaking, causing the ground to behave like a liquid.

Tsunami

A series of ocean waves caused by the displacement of a large volume of water, often due to underwater earthquakes.

Predicting Earthquakes

The scientific efforts to forecast when and where earthquakes will occur, with limited success in short-term predictions.