geology 3 Flashcards
what is groundwater
water that flows underground
porosity-empty space in rock
permeability-rate of water flowing through rock
what is infiltration
water that soaks into the ground
some of aeration
pore spaces contain air and some water
what is the water table
surface where pore spaces only contain water
what is the zone of saturation
area which pore spaces only contain water
what is capillary fringe
area above water table -water is pulled above water table
what does water table depth depend on
amount of rainfall -season -climate -time between rainfalls slope of surface
what are the karst topography structures
sinkholes caves stalactilites stalagmites columns
what is a desert
arid regions characterized by less than 25cm of rain per year
what is the rain shadow effect
air goes over mountain and dry air goes over backside of mountain then absorbs mouisture
5 types of dunes
barchan dune transverse dunes parabolic dunes longitudinal dunes star dunes
what are landslides
movement of loose material down a slope
driving force is gravity
trigger-most common is rainfall
underlying causes of landslides
steep slopes
over-steepening
overloading the top of the slope
deforestation
types of movements and material in a landslide
fall,flow,slide
rock,mud,debris
2 types of shoreline features
depositional-sand moves and deposited by ocean currents
erosional-formed by waves weathering and eroding the shoreline
what is wave energy
depth is 1/2 of wave length
what is longshore current
zigzag motioning surf zone
swash and backwash
how is a glacier formed
snow accumulates faster than it melts
2 types of glaciers
alpine(valley)- form in mountains rivers of ice continental- ice sheets
how does a glacier advance and retreat
advances-when accumulation exceeds melting
retreats-when melting exceeds accumulation
depositional features of glaciers
moraines(till)
lateral
medial
end
what are the river stages
stage 1-v-shaped, few tributaries
stage 2-floodplain develops
stage 3-meandering channel,wide floodplain,oxbows
what is running water
includes all precipitation that falls on land
moves downhill due to gravity
water is an agent of weathering and erosion
what is the source and mouth of a stream
source-a streams beginning, source is a mountain range
mouth-a streams end, a mouth is another body of water
