GEOLOGY

Detailed explanation-1: -Except in the crust, the interior of the Earth cannot be studied by drilling holes to take samples. Instead, scientists map the interior by watching how seismic waves from earthquakes are bent, reflected, sped up, or delayed by the various layers.

Detailed explanation-2: -Geologists study the composition of the Earth’s core using deep drill holes. The Moho separates the crust from the mantle. The composition of the upper mantle is the ultramafic rock peridotite. A gravity meter can be used to explore for metallic mineral deposits.

Detailed explanation-3: -Destructive forces, such as ocean waves, shape the surface by slowly wearing away beaches and other features. Geologists cannot observe earth’s interior directly. It is over 6, 000 kilometers from the surface to the center of Earth. Seismic waves are produced by earthquakes.

Detailed explanation-4: -Drilling To The Mantle Of The Earth : NPR. Drilling To The Mantle Of The Earth Fifty years ago, scientists attempted to drill deep through ocean crust to the Earth’s mantle, an endeavor called “Project Mohole.” That project failed, but scientists are sharpening their drill bits again.