GEOLOGY

Detailed explanation-1: -To study Earth’s interior, geologists also use an indirect method. But instead of knocking on walls, they use seismic waves. When earthquakes occur they produce seismic waves. Geologists record the seismic waves and study how they travel through Earth.

Detailed explanation-2: -These recordings made by a seismograph are called seismograms. Seismic waves travel at different speeds when they pass through different types of material, so by studying seismograms, scientists can learn a lot about Earth’s internal structure.

Detailed explanation-3: -The geologists use rock samples as direct evidence and seismic waves as indirect evidence to study the Earth’s structure.

Detailed explanation-4: -Seismic and the Earth. they came. Geologists use these records to establish the structure of Earth’s interior. The two principal types of seismic waves are P-waves (pressure; goes through liquid and solid) and S-waves (shear or secondary; goes only through solid-not through liquid).