Earthquake Web site to the rescue

When the walls start shaking and the Earth starts quaking, most people run for cover.

But the staff members of the U.S. Geological Survey and the California Institute of Technology's Seismological Laboratory hop into action to capture data on a new, highly networked system of scientific instruments. They can quickly create maps of a quake's intensity and coverage area that can be posted on the Internet to help decision-makers direct emergency response resources.

Following the magnitude 7.1 Hector Mine earthquake in California Oct. 16, 1999, the TriNet project — a public/ private partnership based at Caltech — produced an online "shake map" to help emergency response teams. Usage of the TriNet site peaked at 300,000 hits following the quake.

It used to take hours to create a map that indicated earthquake intensity, said Douglas Given, a USGS geophysicist with the Earthquake Hazards Team at the Caltech Seismological Laboratory. With TriNet, a fairly accurate depiction of the earthquake's impact can be assembled and posted on the Internet within five minutes. TriNet has been in development for about three years.

"With this information, emergency responders can know where to devote their resources," he said.

Given spoke during a May 16 visit by academic researchers and government information technology managers to the lab, based in Pasadena. The visitors were part of the dg.o (DigitalGovernment.Org) 2000 workshop that highlighted National Science Foundation-funded research in technology to enable electronic government.

Besides the shake maps created using instrumental data, TriNet also produces earthquake intensity maps based on information that the public provides by filling out a form on a Web site. In the case of last year's Hector Mine quake, one of these so-called "Did you feel it?" maps was created based on responses from 25,856 users in 1,138 ZIP codes.

Although the ink-on-paper recorder rolls that track ground movement are still associated with earthquake measurement, the scientists who time and analyze seismic waves use far more advanced technology, said Karen Kahler, a seismic analyst at the Caltech lab.

With TriNet, instruments continuously send ground motion data to the Seismological Laboratory's computer systems via frame relay; the Internet; spread-spectrum radio; frequency dedicated, VHF radio; and satellite networks. At the laboratory, computers search data for indications of earthquake characteristics. If an earthquake is detected, subscribers of the California USGS Broadcast of Earthquakes system receive notification on their pagers. A message also is automatically posted on the Internet.

"The hope is to create an early- warning system to halt trains, stop elevators and automatically open fire station doors," Kahler said.