Geology Plates and Layers


Terms in this set (...)

outer core
a layer of molten iron and nickel that surrounds the inner core of Earth
the rigid outer layer of earth, including the crust and upper mantle
plate boundaries
a crack in the lithosphere where two of Earth's plates meet
inner core
a dense sphere of solid iron and nickel at the center of Earth
the layer of rock that forms Earth's outer surface
the study of the solid Earth
the layer of hot, solid material between Earth's crust and core
a section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of continental and oceanic crust
plate tectonics
The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.
Large ancient land mass that was composed of all the continents joined together.
divergent plate boundary
boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them (tension)
convergent plate boundary
boundary between two colliding plates, often associated with mountain building ocean trenches and volcanic islands (compression)
transform plate boundary
Boundary between two plates that are sliding past each other. (shearing)
the molten mixture of rock-forming substances, gases, and water that makes up part of Earth's mantle
upper part of the mantle on which the plates move
stress that stretches rock so that it becomes thinner in the middle
stress that pushes a mass of rock in opposite directions
Stress that squeezes rock until it folds or breaks.
cycling of density where warmer parts rise and the cooler portions will sink.
sea floor speading
the formation of new ocean floor through volcanic activity and at divergent boundaries.