Mono Lake By Emil West

Mono Lake is believed to have formed at least 760,000 years ago, dating back to the Long Valley eruption. Sediments located below the ash layer hint that Mono Lake could be a remnant of a larger and older lake that once covered a large part of Nevada and Utah, making it among the oldest lakes in North America. Mono Lake is a terminal lake in a watershed fed from melting runoff with no outlet. Dissolved salts in the runoff thus remain in the lake and raise the pH and the salt concentration. Mono Lake is in a geologically active area at the north end of the Mono-Inyo Crater volcanic chain of the Long Valley Caldera. The geological activity is caused by faulting at the base of the Sierra Nevada, and is associated with the crustal stretching of the Basin and Range Province. Volcanic activity continues in the Mono Lake vicinity: the most recent eruption occurred 350 years ago at Paoha Island in Mono Lake. Panum Crater (on the south shore of the lake) is an excellent example of a combined rhyolite dome and cinder cone. In order to provide resources for the growing Los Angeles area, water was diverted from the Owens River. In 1941 the Los Angeles Department of Water and Power extended an aqueduct system into the Mono Basin So much water was diverted that evaporation soon exceeded inflow and the surface level of Mono Lake fell rapidly. By 1982 the lake was reduced to 37,688 acres (15,251.8 ha) having lost 31 percent of its 1941 surface area. As a result alkaline sands and once-submerged tufa towers became exposed and Negit Island became landbridged, exposing the nests of gulls to predators (chiefly coyotes) and forcing the breeding colony to abandon the site.

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YouTube | February 6, 2009

Tags:. .predators. .eruption. .exceeded. .fed. .utah