Lake Tahoe: Past due for a magnitude-7 temblor + huge tsunami

Lake Tahoe May Be Due For Huge Quake, Tsunami

Two new studies suggest the Lake Tahoe region has gone longer than usual without a large earthquake and may be due for a magnitude-7 temblor capable of spawning a tsunami that could flood shoreline communities.

The research targeting three major faults was conducted by scientists at the Scripps Institution of Oceanography at the University of California-San Diego.

They determined that earthquakes as large as magnitude-7 historically have occurred every 2,000 to 3,000 years in the Tahoe basin.

But they found that the largest fault in the basin — the West Tahoe Fault running along the west shore of the lake and out the south end just west of South Lake Tahoe — appears to last have ruptured between 4,100 and 4,500 years ago.

The new data suggests that the most recent ruptures along the West Tahoe and Incline Village faults each produced nearly offsets of about 13 feet. The most recent event along the Incline Village Fault occurred about 575 years ago, they said.

"These studies taken together show that the West Tahoe Fault is capable of a magnitude-7 earthquake — similar to large earthquakes that have occurred on the nearby Genoa Fault — but with the added danger of nearly 500 meters (1,600 feet) of overlying water, which is capable of spawning a large tsunami wave," said Graham Kent, a research geophysicist at Scripps.

The analysis suggests an upper limit of a magnitude-7.3 earthquake for the basin's most dangerous fault.

Whole article at: CBS5.com - Link