A magnitude 7.7 earthquake that struck Myanmar on the 28th of last month caused extensive damage. The death toll has surpassed 2,700 within five days, and many buildings have collapsed. Meanwhile, concerns about a major earthquake are growing in California, about 8,000 miles (around 12,875 km) away from Myanmar.
On the 1st (local time), The Washington Post (WP) reported, "Scientists warn that the seismic risks from the Myanmar earthquake are similar to those of earthquakes that could occur along the San Andreas Fault in the western United States," and noted, "Many experts believe the San Andreas Fault has already passed the point where an earthquake could occur."
The epicenter of the Myanmar earthquake is the "Sagaing Fault," which stretches over 1,200 km north to south across the country. The Sagaing Fault is where the Indian Plate and the Sunda Plate meet, and it moves approximately 11 to 18 mm annually. As this movement continues, energy accumulates in the fault over a long period, and ultimately, this force is released in a single moment, resulting in the earthquake.
According to WP, the Sagaing Fault belongs to the "strike-slip fault" category, and earthquakes occurring on this fault tend to cause severe damage over a relatively shallow and wide area. The San Andreas Fault, which runs through California, is of the same type. The San Andreas Fault is where the Pacific Plate and the North American Plate meet.
There are several similarities between the two faults. They are about 750 to 800 miles long and have similar annual movement rates. Amanda Thomas, a seismologist at the University of California, Davis, stated, "The movement rate is crucial information for assessing earthquake risk," adding, "Faster-moving faults tend to produce more frequent and larger earthquakes."
However, the San Andreas Fault has been in a state of "seismic gap" for a long time. As the plates move, accumulated energy will eventually be released, leading to an earthquake. According to the United States Geological Survey (USGS), between 1930 and 1956, there were six earthquakes of magnitude 7.0 or higher near the Sagaing Fault, but there have been no major earthquakes in California for over 300 years.
The problem is that the San Andreas Fault is located in a densely populated area. Los Angeles (LA), located about 30 miles (approximately 48 km) from the San Andreas Fault, houses more than 3 million people. When an earthquake occurs, the potential for loss of life is substantial. The city of Mandalay, where the Myanmar earthquake occurred, also has a population exceeding 1 million, resulting in significant casualties.
However, California has stricter building regulations compared to Myanmar. Structures are better equipped to withstand strong seismic shaking, and reinforcement measures for older buildings have been implemented. Amanda Thomas noted, "These measures can make a significant difference in the number of fatalities and injuries caused by an earthquake."
Zhi Gang Feng, a seismologist at Georgia Institute of Technology, stated, "The Myanmar earthquake may represent a 'super shear earthquake' where shaking is expected to be stronger than anticipated," adding, "Investigating the Myanmar earthquake can help us understand potential earthquakes in regions like the San Andreas Fault."