California‘s seismologists have been on alert and are closely monitoring its complex network of faults. California seismologists are on high alert, diligently monitoring the state’s intricate network of fault lines.
Seismic Risk in California: Understanding the “Big One”.
The San Andreas Fault is an important and very active tectonic fault in California. It could be the cause of a catastrophic earthquake. According to experts, such an earthquake may reach magnitudes of up to 7.8. This magnitude of earthquake could cause widespread damage in densely populated areas such as Southern California and San Francisco Bay Area.
California earthquake preparedness is important
California’s position on active faults makes it prone to earthquakes. This is why the possibility of one occurring in California remains a constant concern. The risk of a major earthquake in California is increasing as the seismic strain accumulates along not only the San Andreas Fault and the many local faults of the state, but also the San Andreas Fault. This occurs particularly on the south side of the State. California needs to take more proactive steps in order to prevent catastrophic damage from occurring. This includes residential areas, critical infrastructure and human life. The implementation of early warning systems is one such measure.
Recent seismic activity fuels concerns
The seismic activity in California has increased significantly over the past few weeks. There have been several recorded earthquakes since mid-February. This has led to increased anxiety that the “Big One’ might be near.
- Avenal Earthquake A magnitude 4.3 earthquake that occurred on the 13th of February, approximately six miles to the north-northwest from Avenal was one of recent’s strongest.
- Hayward Fault: Three earthquakes struck the East Bay on a Thursday. All three quakes, measuring 3.2, 3,3 and 2,6, respectively, originated on the Hayward Fault. It is one of the most well-known features in the San Francisco Bay. Hayward Fault suffered its last rupture, which resulted in a 6.8 magnitude earthquake in 1868.
- Bay Area Tremors Also, an earthquake of magnitude 2.5 was registered approximately 2 miles south-east of Pleasant Hill.
- Northern California Quake In the north, an earthquake of magnitude 2,9 struck at 10 miles from Petrolia.
- Geysers at Anderson Springs and the Geysers: The Geysers near Anderson Springs and The Geysers were both hit by two earthquakes on Friday.
- Malibu Earthquake A magnitude 3.7 quake occurred in the area of Malibu. It was felt 50 miles away, in Los Angeles County including Long Beach and Whittier. And 30 miles in Ventura County.
Although no major damage was reported, earthquake experts are concerned about the increasing frequency of these seismic events, especially after four earthquakes hit Southern California in a single day. Some were near the San Andreas Fault.
Scientists weigh in on California Earthquake risk
Experts say that there is a significant risk for a large earthquake along the Hayward Fault. Hayward Fault poses an important threat to East Bay, which is densely populated. Researchers at University of California Berkeley stated that the clock was ticking since it had been over 150 years since the previous major earthquake. The Hayward fault is likely to rupture within the next thirty years, causing a large earthquake.
Elizabeth Cochran, of the USGS Earthquake Science Center explained that Southern California faces a 36% risk for a magnitude 7 or higher earthquake within the next 30 year. She stressed the importance of personal preparation and awareness about earthquakes, while reminding Californians that it is “earthquake land.” Her remarks also included that seismic fluctuations are common. Ned Field has spent his career refining the earthquake forecasting model Uniform California Earthquake Rupture (UCERF), a tool that quantifies earthquakes’ likelihood in California. The models are regularly updated to include new data, and a better understanding of fault behaviour.
Keith Stuart, an expert in the field of geology and earthquakes, believes that stress accumulation over the years makes the southern portion of the San Andreas Fault most likely to be the location of the next big earthquake. According to the California Earthquake Authority, a magnitude 8 quake could have devastating effects, causing thousands of deaths and injuries as well as billions in damages.
Stuart clarifies, despite concerns that there is no greater risk than in the past of a “Big One”. Dr. Stuart also warns that smaller faults closer to major cities like Los Angeles can cause significant damage. He cites the San Fernando Valley earthquakes of 1971 and 1994 as examples.
California’s Ongoing efforts in earthquake preparedness
California is actively improving its response to disasters, despite wildfires that will occur in 2023. Statewide Health Planning and Development enforces seismic safety regulations for all healthcare facilities. Los Angeles and San Francisco, for example, have retrofitted vulnerable buildings like soft-story and unreinforced brick buildings to reduce earthquake risk.
Experts acknowledge, despite these efforts, that much more work remains to be accomplished, especially in regards to water distribution and transmission systems, critical infrastructure and buildings that have not yet been assessed or retrofitted. It is difficult to maintain public policy attention on these topics, particularly given that it has been a long time since 1994 when the last large earthquake struck a Californian urban area.
Future Seismic Events: Preparedness and Looking Forward
Californians should be informed about the potential timing for the “Big One”. Aftershocks from the California earthquakes will likely be smaller. For the latest information on earthquake activity, it is essential to monitor USGS’s website.