Continental Drift and Plate Tectonics

These flashcards cover key vocabulary and concepts related to the formation of continents and the theory of plate tectonics.

Pangaea

A supercontinent that existed around 335 million years ago, which eventually broke apart into the continents we know today.

Continental Drift

The hypothesis proposed by Alfred Wegener that continents are in constant motion on the surface of the Earth.

Glacial Grooves

Deep scratches in rocks created by glaciers, used as evidence by Wegener to support his hypothesis of continental drift.

Glossopteris

A plant fossil found on multiple continents, supporting the idea that those continents were once connected.

Seafloor Spreading

The process by which new oceanic crust forms along a mid-ocean ridge and older crust moves away from the ridge.

Asthenosphere

The semi-plastic layer of the mantle beneath the lithosphere, allowing tectonic plates to move.

Subduction Zone

The area where one tectonic plate is forced under another plate, often forming deep ocean trenches.

Transform Boundary

A tectonic plate boundary where two plates slide past one another, often causing earthquakes.

Divergent Boundary

A tectonic plate boundary where two plates move away from each other, leading to the formation of new crust.

Convergent Boundary

A tectonic plate boundary where two plates collide, which can result in subduction or mountain formation.