After five earthquakes along the San Andreas fault, this dry riverbed has been offset 10 meters. The lower image shows the location of the fault (white line) and the location of the dry riverbed (blue).
Click on image for full size
Image courtesy of L. Grant Ludwig
New Earthquake Information Unearthed by San Andreas Fault Studies
News story originally written on January 21, 2010
Scientists have taken a new look at the San Andreas Fault in Southern California. What they learned might change our understanding of faults and earthquakes.
To better understand the fault, the scientists took measurements of the Earth's surface. They used a tool that gave them very detailed pictures of the fault. They used the pictures to look at stream channels that cut across the fault. As the fault moves over time, these channels are split apart so that the downstream part no longer matches up with the upstream part. With their new measurements and the detailed pictures, the scientists were able to figure out when earthquakes split the channels apart in the past.
They found that not all earthquakes are the same. The fault acted differently during different earthquakes. If faults slipped the same way each time, then scientists would have a better chance of predicting earthquakes. But if faults slipped differently each time, predicting earthquakes would be difficult.
Strain has been building up on the San Andreas Fault in Southern California for a long time. Someday, the strain will be released in an earthquake. Earthquakes can happen without warning. So, if you live in an area like Southern California where earthquakes are likely, it’s important to be prepared.
Last modified February 26, 2010 by Lisa Gardiner.
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