GEO E111 Lecture Notes - Lecture 31: Offshore Drilling, Soil Retrogression And Degradation, Mass Wasting
Document Summary
L. magadi is 120km s. w of nairobi on the floor of the great rift valley. Trona deposits occur as a solution of sodium salts the main ones being sodium sequicarbonate and sodium chloride. Rain water dissolves soda salts in volcanic rocks. The solution percolates through the rocks and soil and gets beneath the basin. The accumulated solution is heated by the hot rocks beneath. Pressure builds up and the heated solution is pushed to the surface. It comes out of the ground inform of hot springs below or on the sides of the lake. Due to high temperature water evaporates leaving behind crystals of trona. A dredger scoops trona out of the lake. It crushes it into smaller pieces and separates it from rock debris. The material is mixed with water to form slurry and transported to factory on the lake"s shore.
