Flashcards in Groundwater Deck (22)
less than ____ percent of all water in the hydrosphere is groundwater
this is still 40x greater than fresh surface water
about half of all groundwater is found within ____ meters of the surface
below that there is not as much groundwater because there is so much pressure that there is not enough pore space for the water to be stored in
the amount of pore space in a rock depends on the rock's ______
groundwater is stored in the ____ _____ of a rock
the porosity of a rock depends on the _____ and ______ of the grains that make up a rock
the ______ of a rock depends on the shape and size of the grains that make up a rock
if a rock has _____ size grains it has high porosity
a rock has high porosity if it has...
uniform sized grains
uniform sized grains means a rock has ______ porosity
if a rock has ______ size grains it has low porosity
grains of many different sizes
Porosity is the...
amount of pore space in a rock
Permeability is how...
connected the pores are
rocks that store groundwater are known as _______
aquifers are usually a _______ rock
an aquifer must be both _____ and ______
what two sedimentary rocks makes good aquifers?
sandstone and limestone
what is a layer of impermeable rock that confines aquifers?
Aquicludes are usually...
shale or clay
______ aquifers have no aquiclude above them
water is free to rise to its natural levels
if you drill a well into an _____ aquifer you must pump the water to the surface because there is no pressure that's going to force the water out