## How do you describe the location of earthquake epicenters?

The epicenter is the point on the earth’s surface vertically above the hypocenter (or focus), point in the crust where a seismic rupture begins.

## How many seismic waves are needed to locate an earthquake?

Triangulation is required to determine exactly where it happened. Three seismographs are needed. A circle is drawn from each of the three different seismograph locations, where the radius of each circle is equal to the distance from that station to the epicenter.

## How do earthquake waves provide information?

Seismic waves from large earthquakes pass throughout the Earth. These waves contain vital information about the internal structure of the Earth. As seismic waves pass through the Earth, they are refracted, or bent, like rays of light bend when they pass through a glass prism.

## What is the name of the instrument used for measuring earthquake?

Seismographs
Seismographs are instruments used to record the motion of the ground during an earthquake.

## Where do seismic waves start?

Seismic waves are usually generated by movements of the Earth’s tectonic plates but may also be caused by explosions, volcanoes and landslides. When an earthquake occurs shockwaves of energy, called seismic waves, are released from the earthquake focus.

## How do you find the epicenter of an earthquake?

The distance between the beginning of the first P wave and the first S wave tells you how many seconds the waves are apart. This number will be used to tell you how far your seismograph is from the epicenter of the earthquake.

## How are earthquakes recorded at a seismic station?

The different waves each travel at different speeds and therefore arrive at a seismic station at different times. P waves travel the fastest, so they arrive first. S waves, which travel at about half the speed of P waves, arrive later. A seismic station close to the earthquake records P waves and S waves in quick succession.

## Where does the energy from an earthquake travel?

The energy from earthquakes travels in seismic waves, which were discussed in the chapter “Plate Tectonics.” The study of seismic waves is known as seismology. Seismologists use seismic waves to learn about earthquakes and also to learn about the Earth’s interior.

## How are seismic waves used to determine the magnitude of an earthquake?

The amplitude of the waves can be used to determine the magnitude of the earthquake, which will be discussed in a later section.In order to locate an earthquake epicenter, scientists must first determine the epicenter distance from three different seismographs.