GLG 111 Study Guide - Final Guide: Chemical Decomposition, Ocean, Depositional Environment
Document Summary
Porosity: the percentage of total volume of rock or sediment that consists of pore space. Determines the volume of water that the material will hold. Sediments that are well sorted and have rounded gained will have a higher porosity. Permeability: the measure of a water"s ability to transport water. Determined by the porosity and connections between grains. What kinds of rocks have high porosity/permeability versus low. Clay can have porosity as high as 50% Clay has very low permeability because its pore spaces are so small water can"t move through it. Unconfined: an aquifer that is not surrounded by confining beds (more contaminated especially on farms) Water table varies in height due to fluctuations in recharge. Recharge occurs only where the permeable layers are exposed at the surface. What kinds of material make (cid:1688)good(cid:1689) aquifers? contamination cannot get through, this also means that the water table does not fluctuate nearly as much.
