Question

Which statement describes how geologists use data from seismographs to learn about earthquakes?

They often compare information from all over the world.
They map the location of an earthquake’s focus.
They use one reading to determine the location of an epicenter.
They measure the difference between the arrival times of surface waves.

Answer 1

They map the location of an earthquake’s focus.

Explanation: Seismograph readings from several stations are used (by measuring P- and S-wave arrival time differences to get distances) and then triangulated to locate the earthquake’s focus (hypocenter) and epicenter.