EES-1000 Lecture Notes - Lecture 13: Sandpaper, Aquifer, Porosity
6 Nov 2016
School
Department
Course
Professor
Document Summary
*96% of water on earth is salt water. Can only consume water from lakes and rivers (1%) Most fresh water locked within ice and glaciers. Rain shadow area of low rainfall on the leeward slopes. Aquifer sediment or rock (usually sand or gravel) that transmits water easily. Aquitard sediment or rock that hinders water flow. Baton rouge drinking water supplied through the southern hills aquifer. Porosity - % of material volume taken up by pores. Pore open spaces within any sediment or rock. *igneous and metamorphic rocks have very low porosity. Permeability the ease of water flow due to poor interconnectedness. Exposure of the water table at the surface: Surface exposures (eg. streams, ponds) dry up if the water table falls below the bottom. Perched water table forms where a lens of less permeable rock (shale) stops water percolating down to the main water table. Oases in the sahara develop from spring flow.
