How do geologists use earthquakes to obtain information about Earth’s interior?
Geologist use earthquakes as well as what might be called fake earthquakes and seismology to gather data about the earth. In addition to earthquakes. Geologists either drill fairly shallow shot holes, put small amounts of dynamite or explosives in the shot hole, lay out a line grid of geo-phones which will record how the ground moves at that location, and then set off the explosives, or start using a thumper truck to make the ground vibrate. Seismic waves are essentially a sound wave traveling through rock, Every time there is a change of density between different layers of rock, the sound wave is reflected back toward the surface and refracted by change in density. When a natural earth quake happens, the same things happens. Four types of seismic waves can be created during an earthquake. Primary, P-waves and secondary, S-waves, are body waves. S-waves are not transmitted by liquids. That’s how geologists know that the outer core of the Earth is molten. Locating where the epicenter of
