Earthquake FAQs from PHILVOCS

What is An Earthquake? An earthquake is a weak to violent shaking of the ground produced by the sudden movement of rock materials below the earth's surface.

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An earthquake originates in tectonic plate boundary. The focus is point inside the earth where the earthquake started, sometimes called the hypocenter, and the point on the surface of the earth directly above the focus is called the epicenter.

There are two ways by which we can measure the strength of an earthquake: magnitude and intensity. Magnitude is proportional to the energy released by an earthquake at the focus. It is calculated from earthquakes recorded by an instrument called seismograph.