How Are Earthquakes Studied? Seismologists study earthquakes by going out and looking at the damage caused by the earthquakes and by using seismographs. A seismograph is an instrument that records the shaking of the earth’s surface caused by seismic waves.

A seismograph, or seismometer, is an instrument used to detect and record earthquakes. Generally, it consists of a mass attached to a fixed base. During an earthquake, the base moves and the mass does not. The motion of the base with respect to the mass is commonly transformed into an electrical voltage.

Seismograms are used to determine the location and magnitude of earthquakes. An earthquake’s magnitude may be considered to vary as a function of the amount of energy released at the rupture point.

Measuring Magnitude Modern seismometers record ground motions using electronic motion detectors. The data are then kept digitally on a computer. These seismograms show the arrival of P-waves and S-waves. The surface waves arrive just after the S-waves and are difficult to distinguish.

More examples

Though there is no way to pinpoint the exact arrival of an earthquake, scientists can examine sediment samples to get an idea of when major earthquakes occurred in the past. By measuring the amount of time between events, they can come up with a rough idea of when a major quake might hit.

“Every time a small earthquake happens, doesn’t mean there is going to be a larger one,” according to Chung.

Small shallow earthquakes sometimes produce rumbling sounds or booms that can be heard by people who are very close to them. High-frequency vibrations from the shallow earthquake generate the booming sound; when earthquakes are deeper, those vibrations never reach the surface.

No. Neither the USGS nor any other scientists have ever predicted a major earthquake. We do not know how, and we do not expect to know how any time in the foreseeable future. USGS scientists can only calculate the probability that a significant earthquake will occur in a specific area within a certain number of years.

But wait—how would a dog know an earthquake is coming? Dogs have a wider hearing range and better scent detection than humans. Some scientists suggest that dogs can hear seismic activities that precede earthquakes (such as the scraping, grinding, and breaking of rocks underground).

COVER your head and neck (and your entire body if possible) underneath a sturdy table or desk. If there is no shelter nearby, get down near an interior wall or next to low-lying furniture that won’t fall on you, and cover your head and neck with your arms and hands.

Don’t hide under the bed If you are in bed during the night and an earthquake occurs, simply roll off the bed. The bed will hold up some of the debris, creating a safe void around the perimeter. Never get under it, and teach your children never to crawl under the bed in an earthquake.

plate boundaries

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The location below the earth’s surface where the earthquake starts is called the hypocenter, and the location directly above it on the surface of the earth is called the epicenter.

The highest earthquake hazard is concentrated in south-eastern areas of Europe, e.g. Greek, Italy and Romania. With the theory of plate tectonics, it has become evident that most earthquakes occur along the margins of plates, where one plate comes into contact with another, developing shear stresses.

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Latest earthquakes in or near Europe today, past 24 hours, Tuesday, 15 Jun 2021

Indonesia

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