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From July 4 to 5, a magnitude 7.1 earthquake of magnitude 56.4 nuclear magnitude 7.1 hit Southern California located on the west coast of the United States. The earthquake sensation of Los Angeles was strong, but the "Shake Alert LA" alarm system previously launched by the local government in Los Angeles did not issue any warning. In fact, more than a year ago, the U.S. Geological Survey (USGS) issued a warning, saying that a magnitude 9.0 earthquake could occur on the west coast of the United States, and the tsunami that triggered could even cross the Pacific Ocean and affect the Japanese archipelago. Today's California can be said to be shrouded in a haze...
According to USGS data, the epicenter is located near the small California town about 150 miles northeast of Los Angeles, with about 29,000 people. The town's fire department claimed that it was handling casualties, while the hospital was transferring casualties.
Seismologists said that aftershocks will be emitted after this earthquake and will last for a long time, with the possibility of an aftershock exceeding magnitude 5 exceeding 5, and even a larger-scale earthquake may occur in the following areas. In fact, as early as 12 years ago, USGS released a report saying that by 2037, the probability of an earthquake above magnitude 6.7 in the San Francisco Bay Area earthquake is as high as 63%. A geological report in the first half of last year showed that in the next 30 years, a 76% chance of a magnitude 7.0 or above earthquake occurred in urban dense areas in the western United States.
To a certain extent, this earthquake is the best verification. As we all know, the entire west coast of the United States is located above the San Andreas fault. In addition, there are six faults of different sizes that meet in the San Francisco Bay Area. Today, scientists are more worried about whether the Pacific Rim seismic belt will appear from California, which will "activate" the seismic belt in the entire eastern Pacific. You should know that this will directly lead to 11.4 million people facing direct threats.
From the magnitude 6.4 earthquake that occurred on July 4 to the magnitude 7.1 earthquake that occurred on July 5, 159 aftershocks occurred during this period. Meanwhile, seismologists say the earthquake was the largest magnitude earthquake in Southern California since 1999, and although it is sparsely populated near the focal source, it still has the potential to cause damage and casualties. Mayor Lichtres has declared a state of emergency in his area, which is not enough. As of now, the Consulate General of Los Angeles has not received any requests from Chinese citizens.
Is this the slow release of backlog of energy in the fault zone, or is it just an "appetizer" before the real earthquake? Another Cascadia subduction zone (CSZ) that extends from northern California to Canada. The CSZ's fault displacement is large and the angle is low. It is a thrust fault. Often the world's strongest earthquakes occur along these faults. According to records, the time interval between the super earthquake caused by CSZ is 200-530 years, and the last subduction zone earthquake occurred in 1700 (319 years ago), and the threat is self-evident. (The picture below is a screenshot of the movie " Doomsday Collapse ")
"In short, the California area will be affected by more and more serious earthquakes!" said USGS researchers.
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Author/Zhu Zhang Hangyu
Information source: USGS, BI
