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Earth’s Interior
-The structure of the earth was first discovered by studying the
movement of Seismic waves (from earthquakes), and their arrival
times at different places around the globe.
-Earth has a thin (10-30 km thick) crust above a partially molten
mantle.
-The Moho discontinuity (named after Yugoslavian researcher Dr.
Mohorovicic) is the boundary that separates the crust from the mantle.
-Gutenberg, another scientist, discovered there was a shadow
zone where seismic waves do not appear on seismographs. The
shadow zone could be explained if Earth contained a solid core
beneath the mantle. Other readings indicated that at least part of
the core had to be molten.
-The aestheosphere is the upper part of the mantle. This area is
partially composed of molten magma.
-The lithosphere is above the aestheosphere. It is solid and
includes the very top portion of the mantle as well as the entire
crust.
-The earth's core is made up of very dense material, probably a mix
of solid iron and nickel. The outer core is made up of liquid iron and
other heavy materials. Its currents create the earth's magnetic
field, which protects us from solar radiation and other dangerous
incoming particles from space.
-The most common theory is that the Earth’s core is made of iron
and nickel.