Nevada earthquake fault studied

LAS VEGAS - Geologists in Nevada are trying to better understand an earthquake fault west of Pahrump that has the potential to send a jolt to the Las Vegas Valley.

Crews in January began digging three 10-foot-deep trenches along the Stateline fault as part of a research project.

Geologists have known about the fault for decades but scientists may have underestimated its ability to produce a large earthquake, said Wanda Taylor, a geology professor at University of Nevada, Las Vegas.

"We really don't know much about the fault," she said.

Among other things, the research team - which includes Taylor and some students - is hoping to use evidence from the trenches in the Stateline fault to determine the last time it had a major quake.

Whether it was a few centuries ago or several thousand years ago, the answer may offer geologists some clues about how much strain is building up along the fault and how much energy might be released if deep rock layers slide against each other and trigger a quake.

Taylor estimates the fault could produce a magnitude-7 temblor. Seismic waves could make it all the way to the Las Vegas Valley, some 50 miles away, Taylor said.

The amount of damage that would cause would depend on where it's located, the structural integrity of buildings and the kinds of soil they were built on, she said.

Building codes for homes and businesses have been strengthened in recent years to help reduce the dangers of shaking.

But, Taylor said, "If your home is older than 1996, you need to check to be sure the water heater is strapped down."

There are at least 11 seismic faults that either cross the floor of the Las Vegas Valley or are nearby.

Other research is also being conducted along the Stateline fault, including a project by the Civil and Environmental Engineering Department looking at ground-shaking data from a 100-meter-deep bore hole in the fault zone.

Eventually the projects will begin to give a geologists a better look at what's happened along the fault - and what may be still to come.

The work is funded by the Department of Energy as part of a $3 million six-year effort to better understand earthquake hazards in Nevada.