Geologic Trip, Mono Lakes Area
Mono Lake occupies a low spot in one of the many basins in the Basin and Range Province. The Mono Basin was formed when a large block of the earth’s crust subsided along a major fault that goes through Lee Vining. The lake gets most of its water from the Sierra, but has no outlet. Evaporation has increased the salinity so that the lake is more saline than seawater. At several places along the shoreline there are clusters of spectacular white towers of tufa. The towers form where fresh water springs feed into the bottom waters of the lake. The fresh water contains calcium in solution and as the fresh water rises, the calcium in the spring water combines with carbonate in the lake water to form the tufa towers. Although tufa is found in other alkaline bodies of water, the quantity, size, and variety of the tufa towers at Mono Lake is unique.
Geologic background: Mono Lake Area (pdf)
California State Parks: Mono Lake Tufa SNR
Mono Lake Committee: Geology
USGS: Mono Lake Geologic Map
Wikipedia: Mono Lake