Structure of the Earth and Convection Currents

Vocabulary flashcards defining the main layers of the Earth, types of crust, and the mechanism and importance of mantle convection currents.

Crust

The outermost and thinnest layer of the Earth, made of solid rock, where humans, plants, and animals live.

Mantle

The thickest layer of the Earth, made of hot, semi-solid rock (magma), where heat causes convection currents.

Core

The innermost layer of the Earth, made of solid iron and nickel, which remains solid because of extreme pressure.

Oceanic Crust

The crust located beneath the oceans that forms the ocean floor. It is dense, heavier than continental crust, mainly made of basalt, younger, and continuously recycled.

Continental Crust

The crust located beneath the continents that forms the continents and major landmasses. It is less dense and lighter than oceanic crust, mainly made of granite, older, and rarely recycled.

Convection Current

The circular movement of hot and cool material inside the Earth's mantle, caused by heat from the Earth's core.

Mantle Convection Movement

The process where hot mantle material becomes less dense and rises, and as it cools, becomes denser and sinks, moving tectonic plates in the earth's crust.

Importance of Convection Currents

Key geological functions including moving tectonic plates, causing earthquakes and volcanic eruptions, and forming mountains.