CH 20 - Mountain Belts and The Continental Crust

accreted terrane

Terrane that did not form at its present site on a continent

craton

Portion of a continent that has been structurally stable for a prolonged period of time.

fault-block mountain range

A range created by uplift along normal or vertical faults.

fold and thrust belts

A portion of a major mountain belt characterized by large thrust faults, stacked one upon another. Layered rock between the faults was folded when faulting was taking place.

gravitational collapse and spreading

When part of a mountain belt becomes too high, it moves vertically downward, forcing rock at depth to spread out laterally.

lithospheric delamination

The detachment of part of the mantle portion of the lithosphere beneath a mountain belt

major mountain belt

A long chain (thousands of kilometers) of mountain ranges

mountain range

A group of closely spaced mountains or parallel ridges.

orogeny

An episode of intense deformation of the rocks in a region, generally accompanied by metamorphism and plutonic activity.

Precambrian shield

A complex of old Precambrian metamorphic and plutonic rocks exposed over a large area.

suspect terrane

A terrane that may not have formed at its present site

terrane (tectonostratographic terrane)

A region in which the geology is markedly different from that in adjoining regions.