Searles Lake Salt
September 04, 2011
The photo above shows a layer of salt formed on the surface of Searles Lake in California. Salt, yes, but with an interesting formation process. It greatly resembles three-dimensional models of topographic maps frequently used in Physical Geology Lab books. The process involves the evaporation of the brine to create the crusts of salts, but with an ever-decreasing level of brine. The unique aspect of this formation is that the brine level apparently dropped in discrete stages. This allowed a ledge of salt to be formed distinct from those above and below. The somewhat regular spacing of the ledges (which so closely resembles those of contour lines) must have formed over daily cycles of evaporation during a time in which conditions of temperature and evaporation rates were very constant. Counting the ledges indicates this period of constancy to be about two weeks. Photo taken October 10, 2010.