Two Fault Lines In Southern California Are Actually One Big One

Share

A report released Tuesday reveals that a stretch of quake fault between Los Angeles to San Diego Bay would be able to produce a tremor of magnitude-7.4 that could be harm the heavily populated parts of the region.

The connections - or stepovers - between the main parts of the faults are less than 2Km wide. The fault is broken into four main strands separated by three so-called stepovers, or horizontal breaks that are less than 2 kilometers wide.

The two methods used to derive the maximum potential for a rupture of the entire fault found estimates between magnitude 6.7 and magnitude 7.3 to 7.4 quakes, according to the study.

The study, announced Tuesday, looked at the Newport-Inglewood and the Rose Canyon systems. The report's conclusion was that the two systems created a continuous fault that extends beneath the surface of San Diego Bay up to Seal Beach in Orange County, then running through the Los Angeles basin.

'Even if you have a high 5- or low 6-magnitude natural disaster, it can still have a major impact on those regions which are some of the most densely populated in California'.

The researchers processed data from previous seismic surveys and supplemented it with high-resolution bathymetric data gathered offshore by Scripps researchers between 2006 and 2009 and seismic surveys conducted aboard former Scripps research vessels New Horizon and Melville in 2013.

Han Solo Movie Casts The Wire's Michael K. Williams
His recent feature credits include Assassin's Creed and Inherent Vice . He was also part of the Oscar-nominated cast in " 12 Years A Slave ".

Both studies appeared in the American Geophysical Union's Journal of Geophysical Research.

Up until now the Salton trough fault (STF) managed to remain hidden, despite how well-surveyed and seismically active the state of California is, because it is underwater.

Researchers analysed the latest data from the state's complex system of active geological faults, as well as new methods for translating these data into quake likelihoods. Researchers have found evidence of earlier earthquakes of indeterminate size on onshore portions of the fault, finding that at the northern end of the fault system, there have been between three and five ruptures in the last 11,000 years.

In their report, the scientists noted the fault "poses a significant hazard to coastal Southern California" because it runs close to some of the most densely populated parts of the country.

Though most of the fault is offshore, it's never more than 4 miles from the coastline.

In 1933, a magnitude 6.4 quake struck the Long Beach area and killed 115 people. The last major temblor occurred 160 years ago, a catastrophic geological event that ruptured an astonishing 185 miles of the San Andreas fault.

Share