California has
an almost guaranteed chance of being struck by a major earthquake in the next
30 years, Southern California scientists said this week
in the state’s most comprehensive geologic forecast.

The state faces a more than 99-percent chance of being hit
by a magnitude 6.7 temblor — the size of the 1994 Northridge quake — the report
stated. According to the report, there is also a nearly 50-percent chance that California
will experience a magnitude 7.5 quake, which could inflict catastrophic damage
if it is centered in a large city such as San Diego,
Los Angeles or San
Francisco.

“We can expect that we’re going to get hammered by a big
earthquake and we’d better be prepared,” Southern California Earthquake Center
Director Tom Jordan said. “Magnitude 7.5, that’s a really big earthquake.
You’re talking about an earthquake that might span 200 miles of fault length
and a displacement of 12 feet or more.”

Jordan said there is a 37-percent chance that a 7.5
magnitude quake will hit Southern California, compared to a 15-percent chance
in Northern California, largely due to the 1906 San Francisco earthquake, which
relieved stress from the San Andreas Fault in that region.

The 1906 San Francisco
quake was estimated to have a magnitude of around 7.8. The last quake of this
size in Southern California occurred in 1857.

The study was conducted by the U.S. Geological Survey, the
Southern California Earthquake Center and California Geological Survey, and
represents the first report of statewide quake probabilities.