Dunes
Solitary sand dunes shaped like crescents and with their tips pointing downwind.
Barchan dunes.
Significant depositional landforms are created by this element.
wind
A stream that is usually dry because it carries water only in response to specific episodes of rainfall. Most desert streams are of this type.
A glacier confined to a mountain valley, which in most instances had previously been a stream valley.
Alpine Glacier
A thick mass of ice originating on land from the compaction and recrystallization of snow and it shows evidence of past or present flow.
Longitudinal dunes.
Structure in which relatively thin layers are inclined at an angle to the main bedding. Formed by currents of wind or water.
Cross-bedding
A fan-shaped deposit of sediment formed when a stream's slope is abruptly reduced.
Alluvial fan
A glacier that forms when one or more valley glaciers emerge from the confining walls of mountain valleys and spread out to create a broad sheet in lowlands at the base of mountains.
Piedmont glacier
Ice is brittle in this: _______ of _______
zone of fracture
A series of long ridges oriented at right angles to the prevailing wind; these dunes form where vegetation is sparse and sand is very plentiful.
Traverse Dunes
Deposits of windblown silt, lacking visible layers, generally buff-colored, and capable of maintaining a nearly vertical cliff
Loess
A depression excavated by the wind in easily eroded deposits.
Blowout.
The part of a glacier characterized by snow accumulation and ice formation. Its outer limit is the snowline.
Zone of accumulation.
The most widespread feature created by glacial deposition are layers or ridges of till called ______
moraines
The shape of these dunes resembles barchans, except their tips point into the wind; they often form along coasts that have strong onshore winds; abundant sand and vegetation that partly covers the sand.
Parabolic Dunes
The thickest and most extensive deposits of loess on Earth occur in what country?
China - western and northern
A layer of coarse pebbles and gravel created when wind removed the finer material.
Desert pavement
The part of a glacier beyond the zone of accumulations where all of the snow from the previous winter melts, as does some of the glacial ice.
Zone of wastage
Convincing evidence of an ice-age
-multiple layers of drift
-seafloor sediments
- migration of organisms, etc
A solitary sand dune shaped like a crescent with its tips pointing downward.
Barchan dune
the steep, leeward slope of a sand dune; it maintains an angle of about 34 degrees.
slip face
Part a:
A flat area on the floor of an undrained desert basin. Following heavy rain, the playa becomes a lake.
Part B:
A temporary lake in a playa
Playa
Playa lake
The glacial budget is the balance or lack of balance between accumulation at the upper end of a glacier and loss at the lower end.
This loss term is referred to as:
ablation
Two of many hypotheses for the cause of glacial ages
1) plate tectonics
2) variation of earth's orbit