GLG 301 Lecture Notes - Lecture 12: Hydraulic Head, Brackish Water, Hydraulic Conductivity
Document Summary
Storm surges: winds associated with hurricanes pile up water and raises sea level (water cannot flow away on landward side) near eye, worst surges hit places where the ocean floor slope is gentle (e. g. , gulf of. Mexico: particularly bad if it coincides with high tide (storm tide = surge + natural tide, barrier islands often only 5-10 feet above sea level, galveston, 1900. 20 foot storm tide hit galveston (elevation 8 ft), ~8- 10,000 killed: hurricane katrina: billion damage; ~1,800 killed. New orleans proper is below river/lake level. Storm center passed 20 miles east of new orleans, but strong surge from east raised level of lake pontchartrain. Multiple breaches flooded 80% of city to a depth up to 20 feet. Porosity the amount of open space (pores) in a rock (in %: primary porosity (from formation of rock) Gas vesicles in igneous rocks: secondary porosity (formed after formation of rock) Solution cavities (pores left by water dissolving minerals)
