Physical Geology Test 4

It indicates dissolution of underlying soluble rock, generally limestone. Limestone dissolves because rainwater is mildly acidic and this creates topographic features including sinkholes, solution valleys, & disappearing streams.

Surface depressions formed by the collapse of caves or other large underground void spaces.

Valley-like depressions formed by a linear series of sinkholes or collapse of the roof of a linear cave.

Places where water flows naturally from the ground (from spaces in the bedrock)

Streams that terminate abruptly by seeping into the ground.

Created by wind

A dryland that has biological productivity too poor to support any type of agriculture.

Degradation caused by soil erosion, farming without crop rotation or fertilization, overgrazing, or dramatic decrease in soil moisture.

Caused by erosion from streams, flood, rain

A shallow depression developed where wind has eroded and blown ou the soil & fragmented rock usually in a sandy area.

Crescent shaped dunes occuring where sand supply is limited & wind direction fairly constant. Generally form around shurbs or large rocks. Horns or tips point downward.

Occur where sand supply is greater. Form as ridges perpendicular to prevailing winds. Crests generally sinuous.

Somewhat resemble Barchans but horns point in opposite direction-upwind. Always form adjacent to blowouts, the oval depressions from which come the sandy sediments that form the parabolic dunes.

Occur in some modern deserts where sand is abundant and cross winds merge to form high, elongated dunes. Can by quite large. Crests are generally straight to slightly sinuous.

Dryland landform- steep-walled canyon often floored with gravel formed by fluvial erosion.