GEOS 170A1 Lecture Notes - Lecture 12: Mudrock, Aquifer, Himalayas

• School: University of Arizona
• Department: Geosciences
• Course: GEOS 170A1
• Professor: Martin Pepper

Document Summary

Recap: mountains around tucson = divergent, himalayas = convergent & buoyancy, the highest mountains are supported by the deepest roots/thickest crust. Water: distribution of earth"s water = 3% fresh water + 97% saline (oceans, groundwater = largest accessible freshwater reservoir for humans, even though most fresh water is in ice caps/glaciers, groundwater = 1% of fresh water on earth. Liquid water stored in the ground: in fractures, in caves, between grains, water in the ground = aquifer, surface of water = water table. Porosity: sand or sandstone - excellent porosity and permeability, clay or claystone - horrible porosity and permeability, organic mud or limestone - horrible porosity and permeability, fractured rocks like limestone - better. Why would we want impermeability? (density: water = 1g/cm3, crude oil = A big deal: pore spaces are held open by water, pumping out water reduces spaces, less pore space for later water recharge, more flooding in the future!