Wowzers!!! Three adventures in a week and this one more of an unusual location for us! The flat and very low-lying Salton Sea area.
The Salton Sea is that big darn lake that has a higher salinity than the Dead Sea, that you see on maps of the low desert of California including the Coachella and Imperial Valleys in Riverside and Imperial County and the Lower Colorado River Basin. It’s difficult to realize how big of an area it covers until you actually see it. The current lake is about 15 miles wide and 35 miles long with a surface elevation of approximately 236 feet below sea level with a maximum depth of about 43 feet. That makes the bottom of the Salton Sea only 3 feet higher than the elevation of Badwater Basin in Death Valley, the lowest point in the US.
To add to the story, the Salton Sea is landlocked in a closed drainage basin; it is in one of the most faulted areas of California; the San Andreas Fault ends at Bombay Beach on the northeast shore and if you are ever asked to bet where the next volcanic eruption in California will be, I would recommend you bet on the Salton Buttes area.
As far as the long-term history of the Salton Trough, the Gulf of California (Sea of Cortez) would extend as far north as Indio, 150 miles northwest of its current limits, were it not for the delta created by the Colorado River. Over three million years, through all of the Pleistocene Epoch, the Colorado River delta expanded until it cut off the northern part of the gulf. Since then, the Colorado River has alternated between emptying into the basin, creating a freshwater lake, and emptying into the gulf, leaving the lake to dry and turn to desert. Wave-cut shorelines at various elevations record a repeated cycle of filling and drying over hundreds of thousands of years. The most recent freshwater lake was Lake Cahuilla. It covered over 2,000 square miles of the basin, six times the area of the Salton Sea. It goes without saying, eventually, the delta will be destroyed, and the Gulf will creep northward until most of the Coachella Valley becomes ocean front property.
While there had been previous lakes in what is now known as the Salton Sea and beyond, the Salton Sea as we know it did not exist. Short story is that prior to 1900 it was dry land farmland. An irrigation canal was constructed, and the area now inundated as well as significantly beyond the Salton Sea flourished as irrigated farmland The history is somewhat convoluted and tied closely to development of the agriculture in the Imperial Valley. The irrigation canal constructed in 1900 became silted in and an engineer for the canal company/owner authorized construction of an uncontrolled breach in the Colorado Riverbank downstream of the obstruction. A wet year with well above average snow melt in 1905 caused the Colorado River to flood and for two years, the entire flow of the Colorado River was diverted into the Salton Sea. After significant intervention, the breach was closed in early 1907.
Since then, the history of the Salton Sea has been one of litigation, politicizing, lying, cheating, environmental degradation and resurgence, fortunes made and lost and general blundering. But what about those volcanos aka the Salton Buttes that we drove south to see.
The Salton Buttes are a group of relatively low relief volcanoes, on the southeast shore of the Salton Sea. They consist of 4-mile-long row of five lava domes, named Mullet Island (located offshore), North Red Hill, Obsidian Butte, Rock Hill and South Red Hill. They are closely associated with a geothermal field, and there is evidence of near surface (5,000 – 10,000 ft bgs) magma.
This is a relatively abbreviated discussion of the history of the Salton Buttes. The Salton Buttes lie within the Salton Trough, a tectonic depression formed by the San Andreas Fault and the San Jacinto Faults. The depression forms the northward extension of the Gulf of California and is separated from it by the Colorado River Delta. A number of geothermal and volcanic features are located in the area, which is a region of active seafloor spreading. There are several geothermal plants visible from the Salton Buttes area. Within the immediate vicinity of the Buttes, there are also mud volcanoes. Access to these is controlled as you never can tell what moronic prank the general public the public is going to do in their never-ending goal of achieving the elusive 5 minutes of fame.
The Salton Buttes formed within the last 10,000 years during the current Holocene epoch, mostly through relatively viscous flows of iron rich lavas, highly gas charged pumice and ash. Future eruptions are possible and likely depending on how long of a time is associated with the word likely.
The pictures below show a variety of views of the Rock Hill volcano, some longer distant views of the North and South Red Hill Volcanoes and a plethora of Obsidian Butte and the collecting of obsidian for the Taos Ct. pictures. The last group of photos is from Bombay Beach (the southern terminus of the San Andreas Fault) located on the which houses an eclectic collection of humanity in a small community that at one time was a thriving resort on the beautiful shores of the now somewhat stinky Salton Sea. There is a very fine bar and food stop called the Ski Inn in Bombay Beach where the burgers are fine, the beer is cold, the jukebox has great tunes from my generation and all of the walls and ceilings are covered with signed dollar bills from previous clients.
