Earth interior

1906

Earth interior

The book of science

Tom Sharp

Richard Dixon Oldham, Andrija Mohorovičić geophysics

Earth interior

Seismograph

Earthquakes

The Earth’s core is composed of iron and nickel, with a molten outer core and a solid inner core. The depth of the Moho discontinuity is as little as five kilometers under oceans and as much as sixty kilometers under continents. Seismic waves that hit this discontinuity are slowed, reflected, and refracted by the change in composition of rock.

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