Plate Tectonics Overview

The process where new oceanic crust is formed at mid-ocean ridges and then moves away from the ridge axis.

The Earth's outermost layer, made of rigid crust and the uppermost mantle.

Large, rigid sections of the Earth's lithosphere that move and interact with each other.

The point on the Earth's surface directly above the origin of an earthquake.

The process by which continents drift across the Earth's surface driven by the movement of tectonic plates.

The theory that explains the movement of the Earth's lithosphere, including continental drift and seafloor spreading.

Magma erupts at mid-ocean ridges, cools, and creates new oceanic crust with magnetic characteristics.

The Earth's interior heat drives convection currents in the mantle, which causes the movement of tectonic plates.

A supercontinent that existed millions of years ago, comprised of all the present-day continents, before drifting apart.

Identical rocks of the same type and age found on opposite sides of the Atlantic Ocean, supporting the idea of continental drift.

Areas where two tectonic plates slide past each other horizontally.

Mountain ranges with identical rock types, structures, and ages located on continents now separated by the Atlantic Ocean, suggesting they were once a single range.

Volcanic islands formed along subduction zones, where one plate slides beneath another.

Fossil evidence of the same extinct species found on widely separated continents, indicating they were once connected and the organisms lived side-by-side.

The true size and shape of a continent, extending beyond the visible landmass to include the submerged underwater shelf.

A massive mountain range formed by the collision of two continental plates.

A region encircling the Pacific Ocean with high volcanic and earthquake activity due to subduction zones.

Alfred Wegener proposed that the continents were once united into a single supercontinent named Pangaea, meaning all earth in ancient Greek and that the continents then moved to their current positions.

The process of one tectonic plate sliding beneath another.

Areas within a tectonic plate, not at plate boundaries, where volcanic activity occurs.

A pipe of hot rock rising from deep within the mantle, causing volcanic activity.

Regions where volcanic activity occurs due to mantle plumes.

A chain of volcanoes formed by a stationary plume of magma rising from the Earth's mantle.

A location where tectonic plates move apart, creating new crust.

A location where tectonic plates collide, resulting in one plate subducting under the other.

A mountain range formed by volcanic activity along a convergent plate boundary.

A mountain range formed by the collision and uplift of tectonic plates.

A supercontinent formed by the collision of continents.

Fossils of the same plant or animal species found on different continents, providing evidence for continental drift.

A mountain range on the ocean floor that marks a boundary between tectonic plates, where magma rises from the Earth's mantle to form new crust.

A deep trench or valley in the ocean floor where the ocean floor is subducted (pulled beneath) into the Earth's interior.

A device used to measure the depth of the ocean floor by sending sound waves that bounce back to the ship.

The study of the ocean floor's topography, including its depths, valleys, ridges, and other features.

The collection of data and information, often in a more organized or structured form, gathered during World War II.

A map showing the depths of the ocean floor, as if the water were removed.

Deep, narrow trenches in the ocean floor, often located near continents or volcanic areas.

Large, flat areas on the ocean floor.

The alternating pattern of normal and reversed magnetic polarity found in the ocean floor rocks.

The oldest seafloor is found near continents and trenches, while the youngest seafloor is found at mid-ocean ridges.

The theory that explains how new ocean floor is created at mid-ocean ridges and then moves away from the ridge.