deserts and wind eolian - exam 1 Flashcards
how does sediment move?
water
gravity
ice
wind
a dry area on the lee side of a mountain range
rain shadow desert
constant wind direction
limited sand supply
barchan dune
constant wind direction
large sand supply
transverse dune
converging winds
limited sand supply
longitudinal dune
the most important erosional agent non the desert
water
wind removes finer grained material and coarse material is left behind as a surface layer
desert pavement formation
a cobble or pebble polished and shaped by the sandblasting effect of wind
ventifacts
fan shaped deposit of sediment when a stream’s slope is abruptly reduced
alluvial fan
an apron of sediment along a mountain front created by the coalescence of alluvial fans
bajada
a stream that consists of numerous intertwining channels
braided stream
the flat, central area of an undrained desert basin
playa
a temporary lake in a playa
playa lake
an isolated mountain remnant characteristic of the late stage of erosion in a mountainous arid region
inselberg
causes loss of soil and vegetation in a desert
blowout
produced when rocks become abraded by windblown sediment
ventifacts
mounts and ridges of sand formed by sediment carried as part of the wind’s bed load
dunes
extensive blankets of silt carried by wind in suspension
loess
the two types of wind deposition
dunes and loess
the basin and range region is characterized by
interior drainage
responsible for most of the erosion work in a desert
running water
the channels are carved largely by flash floods during sporadic storm events, these are called
ephemeral streams
in dry lands, rock weathering is greatly
reduced
dry climates cover about __ of earth’s land area
30%
