California on High Alert: Experts Warn of Increased Quake Risk as Swarm Continues for 4th Day

California is bracing for the possibility of a major earthquake after a swarm of tremors hit the San Ramon area for the fourth consecutive day. The US Geological Survey (USGS) reported a 3.1-magnitude quake near San Ramon on Tuesday, followed by a dozen smaller quakes in the same area. The recent seismic activity has left residents concerned, but experts do not believe it is a warning sign for a larger quake. Annemarie Baltay, a USGS research geophysicist, said the small events are not indicative of an impending large earthquake. However, she emphasized that it is essential for residents to be prepared for a significant event. According to USGS data, there have been at least 21 earthquakes in San Ramon over the past two months, with at least 90 recorded in the last month alone. The city has experienced multiple quakes in the past, with similar swarms occurring in 1970, 1976, 2002, 2003, 2015, and 2018. Experts have warned that there is a 72% chance of a magnitude 6.7 or larger earthquake occurring in the Bay Area between now and 2043. While the recent swarm does not indicate an immediate threat, it serves as a reminder of the region's seismic activity. Roland Burgmann, a UC Berkeley seismologist, suggested that the recent quakes could be a tense aftershock sequence, given that the first quake in November was the strongest. Sarah Minson, a research geophysicist with the USGS, attributed the swarm to fluid-filled cracks in the area's complex fault geometry. As the region remains on high alert, residents are advised to remain prepared and vigilant for any signs of increased seismic activity.