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Seismologists create satellite network to monitor Earth's creep By Andrew Bridges, Associated Press, 7/6/2001 16:24

LOS ANGELES (AP) After a decade of work, the last of 250 satellite monitoring stations was installed this week in a network that will allow earthquake scientists to measure with unprecedented precision the slightest movements of the Earth's crust.

Measuring this subtle creep will help scientists determine how much strain is building up along faults in the crust. That, in turn, could help them assess the risk of an earthquake.

The network employs the same orbiting set of Global Positioning System satellites that hikers, motorists and U.S. soldiers use to pinpoint their location anywhere around the globe.

''We have in Southern California over half of the nation's earthquake risk, and we are applying GPS technology in new ways to assess this risk,'' said Ken Hudnut, who is head of the project at the U.S. Geological Survey.

Standing on spindly legs, and painted a dull gray, the monitoring stations have been placed across a wide swath of Southern California and Mexico's Baja California peninsula. The stations sit on private property, alongside freeways, atop dams and, in at least one case, on an oil drilling platform. The 250th station was installed Monday.

The GPS stations will provide continuous data for 50 years or more. The network can record as little as .04 inches of distortion of the ground or movement along a fault.

''Southern California is wired like no place else in the U.S.,'' said John Filson, national program coordinator of the USGS's earthquake hazards office.

NASA's Jet Propulsion Laboratory and the Scripps Institution of Oceanography are also major participants in the project.

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-- Anonymous, July 06, 2001