Which is a method that scientists use to determine the composition of earths layers

Seismograms

Explanation:

which are recordings produced by seismographs, are the main way that scientists know what Earth's interior is made of. We can see that the crust is solid material, but we require body waves to tell us about the rest of it. We know that the mantle is solid because both P and S waves travel through it.

answergeosphere;