The stress is building up along the San Andreas and a large earthquake is inevitable.
Two new scientific publications corroborate this apocalyptical scenario: (1) Discovery of a newly identified fault line that could unleash a magnitude-7.4 earthquake in the region, (2) South California is already long overdue for a ‘Big One’ along the infamous San Andreas fault.
The concerns are detailed in separate studies that put the quake risks of the USA’s most populous state into much sharper focus.
The newly identified fault line is capable of a powerful quake that would impact 20 million residents of Los Angeles and San Diego, according to a study published Tuesday. The fault runs underwater from San Diego Bay to Seal Beach in Orange County and on land through the Los Angeles basin.
In the meantime, areas north of Los Angeles may be long overdue for a ‘Big One’ along a portion of the San Andreas fault, according to a second study. Over the past 1,200 years, large earthquakes occurred there about every 100 years.
Newly identified fault
In the first study, the newly identified fault line is mostly offshore but never more than four miles from the San Diego, Orange County, and Los Angeles County coast. Even a high magnitude-5 to a low magnitude-6 quake can still have a major impact on those regions, which are some of the most densely populated in California.
The fault, officially known as the Newport-Inglewood/Rose Canyon fault zone, caused a 6.4-magnitude quake in Long Beach, Calif. that killed 115 people in 1933. About 3 million people lived in the entire Los Angeles metro area at that time. Today, that number is 13 million.
The Newport-Inglewood and Rose Canyon faults were considered separate system, but the study found they are actually one continuous fault system.
The last ‘Big One’
From the second study we learn that the last ‘Big One’ in southern California was a magnitude-7.7 to 7.9 in 1857 and thus that a major earthquake is way overdue on a 100 mile stretch of the San Andreas Fault from the Antelope Valley to the Tejon Pass and beyond.
At that time, the population of the entire state of California was less than 100,000 people. Today, it’s 37 million.
The land on each side of that portion of the San Andreas fault has been crushing together at a rate of over 1 inch per year since 1857. This is causing accumulating energy that will be released in a major earthquake, when the land along the fault would move by many feet.