San Andreas Fault Stressed By IrrigationBy: Lindsay McCane - May 14, 2014
On Wednesday, the journal of Nature released their most recent findings regarding the San Andreas Fault.
According to the study, excessive irrigation could be aggravating the fault, causing more frequent earthquakes. GPS readings have shown that parts of the floor of the San Joaquin Valley have been diminishing while the nearby mountains are being lifted higher. These motions are causing stress on the nearby faults, including the San Andreas.
Colin Amos, the lead researcher and a geologist at Western Washington University, wrote an email about their findings. “The magnitude of these stress changes is exceedingly small compared to the stresses relieved during a large earthquake,” he said.
Paul Lundgren of the NASA Jet Propulsion Laboratory, who did not take part in the research, explained that human activities “can cause significant unclamping of the nearby San Andreas Fault system.”
Shockingly, in the past 100 years, the amount of groundwater that has been lost through irrigation in the Central Valley is equivalent to the amount of water in Lake Tahoe. The current drought that has bombarded California has also contributed to the loss of groundwater, as the community is having to tap into their supply.
The San Andreas Fault is one of the largest in California, running approximately 800 miles from just north of San Francisco to the Salton Sea near the United States/Mexico border.
Scientists have revealed that if a magnitude 7.8 earthquake were to occur near the southern part of the fault, it could cause the deaths of nearly 1,800 people and $200 billion in damages.
Image via Wikimedia Commons