New fault discovered at Salton Sea

Researchers Wednesday, detailed their discovery of a fault line running along the eastern edge of the Salton Sea and parallel to the San Andreas Fault, near where a swarm of nearly 200 small earthquakes struck last week. The discovery of the “Salton Trough Fault,” described in the October issue of the Bulletin of the Seismological Society of America, is receiving wider recognition in the wake of the earthquake swarm situated in the Salton Sea last Monday. The swarm heightened fears of “The Big One” striking and prompted the Governor’s Office of Emergency Services to issue an earthquake advisory warning of an increased chance of a major temblor — magnitude-7.0 or higher — between Sept. 27 and Tuesday. Scientists from UC San Diego’s Scripps Institution of Oceanography and the Nevada Seismological Laboratory collaborated on the discovery, which they say could prove vital to seismic hazard models that predict the damage a potential major earthquake could cause. “To aid in accurately assessing seismic hazard and reducing risk in a tectonically active region, it is crucial to correctly identify and locate faults before earthquakes happen,” said Valerie Sahakian, lead author of the study. Scientists say more research is needed to determine how the trough fault interacts with the southern San Andreas Fault and what role it has played in the 300 years since the San Andreas Fault’s last major earthquake event. “We need further studies to better determine the location and character of this fault, as well as the hazard posed by this structure,” Sahakian said. “The patterns of deformation beneath the sea suggest that the newly identified fault has been long-lived and it is important to understand its relationship to the other fault systems in this geologically complicated region.”