Plate Tectonics Flashcards
Divergent Boundary
Occurs where plates move apart. Most are found in the ocean
Convergent Boundary
Occurs when plates push together
Continental Drift
Earth’s continents were once joined in a single land mass and gradually moved, or drifted, apart.
Theory of Plate Tectonics
Earth’s lithosphere is made up of huge plates that move over the Earth’s surface.
Convection Currents
A sinking and rising motion that transfers heat energy in a material.
Transform Boundary
Occurs where plates scrape past each other.
Rift Valley
A wide gap formed by spreading mid-ocean ridges.
Mid-Ocean Ridges
Huge underwater mountain ranges.
Asthenosphere
Layer of hotter softer rock in the upper mantle.
Lithosphere
Earth’s crust and the very top of the mantle together.
Hot Spot
Heated rock rises in plumes, or thin columns, from the mantle.
Subduction
When one plate sinks beneath another.
