Researchers found a pattern of Colorado River waters pouring into Lake Cahuilla and accompanying large earthquakes before the lake periodically dried up. By contrast, the Salton Sea currently reaches a height of about 240 feet below sea level, and with a maximum depth of about 50 feet. Lake Cahuilla was so vast that it stretched from the Coachella Valley south into Mexico and from as far west as Plaster City, California, to as far east as the Chocolate Mountains, according to study co-author Thomas Rockwell, a professor of geology at San Diego State.Ī full Lake Cahuilla reached an elevation of about 40 feet above sea level, with a maximum depth of more than 300 feet before it started to spill again. The ancient predecessor to the Salton Sea is now referred to as Lake Cahuilla, which, when full, was 40 times larger in volume than its modern-day remnant. So what could explain this unusually long quiet period?īefore the Salton Sea began to form in 1905-the result of both human and natural causes-the low-lying Salton Trough, which sits below sea level, cycled over thousands of years between filling with water from the Colorado River and drying out. More than 1,000 of those deaths could occur in L.A. That envisions a magnitude 7.8 earthquake that could result in 1,800 deaths and nearly 50,000 injuries-the deadliest quake in modern Southern California history. "And so this area actually poses the largest seismic hazard in all of California because it could severely damage the Los Angeles metropolitan area."Ī plausible earthquake that begins at the Salton Sea and ruptures through Palm Springs, continuing to Los Angeles County, is known as the ShakeOut scenario. Hill, a doctoral candidate in geophysics at the Scripps Institution of Oceanography and San Diego State who was lead author of the study. "Yet we know that this portion of the fault has accumulated enough tectonic strain to produce such an event," said Ryley G. For others, the gaps were probably as long as 280 years.īut it's been about three centuries-sometime between 17-since a temblor that was at least a magnitude 7 struck the southernmost section of the San Andreas. Some were probably separated by only a 40- or 50-year gap. In this southernmost section of the San Andreas, there have been seven major earthquakes between the 10th and 18th centuries. A section between Monterey County and San Bernardino County ruptured 166 years ago, and another portion ruptured in the great San Francisco earthquake 117 years ago. Other sections of the San Andreas have ruptured more recently. A drying Salton Sea may be helping delay the next Big One, but that could result in a more powerful quake when it does strike.Ī study published Wednesday in the journal Nature by scientists at San Diego State University and the Scripps Institution of Oceanography at UC San Diego aimed to help explain why the southernmost tip of the San Andreas fault, close to the Mexican border, hasn't had an earthquake of a magnitude 7 or greater in about 300 years. The drought of earthquakes on the San Andreas fault will not last. Never was a solemn solitude turned into teeming life quicker.A new study provides a possible answer-the drying Salton Sea, about 150 miles southeast of L.A., and the lack of sudden, major floodwaters funneling into it since it formed more than a century ago.īut one thing is certain. “Every door, of every house, as far as the eye could reach, was vomiting a stream of human beings and almost before one could execute a wink and begin another, there was a massed multitude of people stretching in endless procession down every street my position commanded. Never was a solemn solitude turned into teeming life quicker.” The streetcar had stopped, the horses were rearing and plunging, the passengers were pouring out at both ends, and one fat man had crashed halfway through a glass window on one side of the car, got wedged fast, and was squirming and screaming like an impaled madman. “And here came the buggy-overboard went the man, and in less time than I can tell it the vehicle was distributed in small fragments along three hundred yards of street. Mark Twain later recounted a harrowing scene: Several successive earthquakes jockeyed for prominence when it came to the phrase “San Francisco earthquake” before 1906, including this now-obscure 19th century tremblor.
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