Physical Geography Key Terms (pt 1)

Plate Tectonics Theory which states that the earth’s outer shell consists of plates that move causing earthquakes, volcanoes, mountains and the formation of new crust.

Erosion Wearing away of earth’s surface followed by the movement to other locations of materials that have worn away.

Fossils Imprint in rock of the remains of a plant or animal that lived millions of years ago

Geologic time History of the earth from its formation to the present. The earth’s history may be divided into several major time periods, called eras.

Eras Major division of geologic time (for example, the Paleozoic era)

Canadian Shield Large area of Precambrian rock that forms the core of Canada.

Folding Bending of rock layers

Faulting Movement along a crack (fault) or cracks in the earth’s crust

Igneous Rock Rock formed from cooling molten rock (magma or lava)

Metamorphic Rock Type of rock formed when sedimentary and igneous rocks are subjected to great heat and pressure

Sedimentary Rock Rock usually formed in layers from the compression of sediments over millions of years.

Ice Age Period or time when freezing temperatures created ice sheets across continents. Glaciers covered most of Canada and northern U.S. The last Ice Age ended between 6000 and 10000 years ago.

Glaciers Slow moving mass of ice.