An earthquake with a magnitude close to 4.0 shook the area of Los Angeles, California, at dawn on Monday, April 5. The natural phenomenon reactivated the concern of specialists about the San Andreas Fault and the worry of a mega-earthquake that would put the area at risk, the “Big One”.
According to data from the United States Geological Survey (USGS), the epicenter was located east of Los Angeles International Airport, on the south side of Hollywood Park. The quake was recorded at 4:44 a.m. Monday, local Los Angeles time. In addition, other mild tremors were recorded throughout the metropolitan area. To the relief of Angelenos, no significant damage or casualties were estimated. However, all is not so quiet in the area.
Experts on the subject began to be alarmed by the possible effect on the San Andreas Fault, one of the most feared geographic features in the world. In the last 10 days there have been three earthquakes of magnitude 3 or more in places near Los Angeles.
The area is considered to have high seismic activity and is crossed by the famous San Andreas Fault. According to USGS estimates, it is believed that there is a 60% chance that an earthquake with a magnitude close to 7 will occur in Los Angeles in the next 30 years and the Fault is the place where the chances grow the most.
In 2019, the Long Beach National Earthquake Conference had stated that the Southern California section of the San Andreas Fault was “charged and ready to generate a large earthquake.” Although the warnings date back to 2016.
Tremors in California always generate fear about the “Big One,” a mega-quake of catastrophic proportions that seismologists say should have already happened.
What is the San Andreas Fault
The San Andreas Fault is a key element in this predicted natural disaster, as it crosses the entire state from north to south and has an extension of more than 1300 kilometers. The fault is the one that defines the boundary between the North American tectonic plate and the Pacific plate. It is one of the most analyzed in the world due to the fact that almost all of it is located on the earth’s surface. On its axis are located large urban conglomerates such as Los Angeles and San Diego, populations with millions of inhabitants.
The middle part of the fault ruptured 160 years ago, while the northern part broke in 1906 and caused the brutal 7.8 earthquake that killed 3,000 people in San Francisco. Since then, the plate has not generated earthquakes again and continues to accumulate tension, which could lead to another violent earthquake.
The southern part of the plate is the one that generates more concern, since it has not fractured for more than 300 years. The last recorded earthquake in the area was in 1700. Computer calculations that recreated the possible effect of the “Big One” assure that it could have a magnitude of up to 7.8 and cause at least 2,000 deaths, in the most optimistic forecasts. About 1% of the buildings in an area with 10 million people would collapse and there would be some 50,000 injured.