Deep angles along San Andreas mean temblors may be stronger than predicted
A new twist on the San Andreas fault could shake up southern Californians preparing for the Big One.
The southern San Andreas isn’t vertical in most places, as previously thought. Instead, it twists in opposite directions along its length, a new study finds, meaning a rupture might shake some places harder than current forecasts predict.
“We now have a picture of a propeller-shaped San Andreas,” says Gary Fuis, a geophysicist at the U.S. Geological Survey in Menlo Park, Calif. Fuis and his colleagues report the new findings in the February Bulletin of the Seismological Society of America.
This shape could make the San Andreas — parts of which have been locked and building up strain as the Pacific and North American plates try to slide past each other — even more hazardous.
“The dipping geometry may allow for significantly larger earthquakes,” says Roland Burgmann, a geophysicist at the University