8th Grade Unit 5 Plate Tectonics Vocabulary

Front

Law of Superposition

Back

Each rock layer is older than the one above it.

Front

Plate Tectonics

Back

Earth's surface is broken into large pieces called plates that are constantly moving and changing at a very slow rate.

Front

Harry Hess

Back

An American geologist who confirmed Wegener’s ideas of continental drift by using the evidence of seafloor spreading.

Front

Fossil

Back

The impression of a prehistoric organism preserved in rock.

Front

Geologist

Back

A scientist who studies the Earth, including its rocks, minerals, landforms, and the processes that shape its surface.

Front

Mid-Ocean Ridge

Back

An underwater mountain range formed by plate tectonics.

Front

Rift Valley

Back

A lowland region formed by the divergence of tectonic plates.

Front

Seafloor Spreading

Back

The process by which new oceanic crust is formed at mid-ocean ridges and older crust is pushed away.

Front

Pangaea

Back

A supercontinent that existed during the late Paleozoic and early Mesozoic eras.

Front

Asthenosphere

Back

The semi-fluid layer of the mantle on which tectonic plates float.