Earth Layers and Tectonic Plates

Vocabulary flashcards covering Earth's structure, tectonic plates, rock types, the rock cycle, fossils, and surface processes including weathering, erosion, and deposition.

Crust

One of the two outer layers of Earth, made mostly of rocks and minerals.

Mantle

One of the two outer layers of Earth, made mostly of rocks and minerals.

Outer core

One of the two inner layers of Earth, made mostly of iron and nickel (metals).

Inner core

A very hot inner layer of Earth made mostly of iron and nickel (metals).

Tectonic plates

Sections of Earth's crust the size of continents that constantly move very slowly due to Earth's thermal energy.

Plate boundary

A location that forms where two tectonic plates meet each other.

Convergent boundaries

Plate boundaries that occur when plates move toward each other.

Divergent boundaries

Plate boundaries that occur when plates move away from each other.

Transform boundaries

Plate boundaries that occur when plates slide past each other.

Faults

Cracks in the Earth's crust where plates have been moving.

Sedimentary rock

Rock formed by sediment (small pieces of rock) cementing together.

Igneous rock

Rock formed as magma or lava cools and hardens.

Metamorphic rock

Rock formed by heat and pressure.

Rock cycle

The series of changes where rocks constantly move and transform from one type to another.

Fossils

Preserved remains of plants or animals from the past.

Weathering

The process that occurs when solid rocks on Earth's surface are broken down into smaller pieces by water, air, plants, and chemicals.

Erosion

The process that occurs when natural forces like water, wind, and gravity move weathered material from one place to another.

Deposition

The process that occurs when broken-down pieces of rock are dropped in a new place as sediment.