The central, innermost, or most essential part of anything.
Core
Is dense yet fluid in places and is responsible for volcanoes and the movement of tectonic plates.
Uppermantle
The innermost part of a core.
Inner core
The continuity of a body of rock .
Fault
The middle portion of earth.
Mantle
The region between the ionosphere and the exosphere.
Mesosphere
The thinnest layer of the earth.
Crust
The bottom portion of the mantle.
Lower Mantle
The outermost part of the core.
Outer Core
The continent that used to be alive but was separated by the movement of tectonic plates.
Pangaea
A portion of strata that is folded or bent, as an anticline or syncline, or that connects two horizontal or parallel portions of strata of different levels.
Folding
Molten material beneath or within the earth's crust, from which igneous rock is formed.
Magma