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The Question & Answer (Q&A) Knowledge Managenet

The Internet has many places to ask questions about anything imaginable and find past answers on almost everything.

Table of Contents

- What is the formula used in finding the distance of epicenter?
- What is an epicenter distance?
- How can you find the epicenter of an earthquake?
- How are P and S waves used to determine the location of an earthquake?
- How is the depth phase of an earthquake determined?
- What is the travel time curve of an earthquake?

If a lag time of 15 seconds corresponds to 100 miles of distance to the epicenter, how far is the epicenter from another recording station, if that lag time is 30 seconds? Since the question is “how far,” you should use the distance formula, Distance = Velocity X Time.

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. According to the chart, this earthquake’s epicenter was 215 kilometers away.

Using the arrival times of the P and S waves from 3 different stations distances to epicenter can be determined. The intersection of the 3 cirles gives epicenter location. Each station on the interactive map recorded an earthquake with a characteristic seismogram.

The arrival times of P and S waves are used to determine the distance to an earthquake using standard travel-time curves. P & S waves each shake the ground in different ways as they travel through the Earth. P waves are faster than S waves so by looking at seismograms,…

The depth phase is the characteristic phase pP-a P wave reflected from the surface of the Earth at a point relatively near the hypocenter. At distant seismograph stations, the pP follows the P wave by a time interval that changes slowly with distance but rapidly with depth.

A travel time curve is a graph of the time that it takes for seismic waves to travel from the epicenter of an earthquake to the hundreds of seismograph stations around the world. The arrival times of P, S, and surface waves are shown to be predictable.