Conference Papers

The U.S. Geological Survey (USGS) is the lead federal agency of the National Earthquake Hazards Research Program (NEHRP) to conduct research related to earth sciences. Therefore, whether it is research on structures or other civil engineering disciplines, the subject matter of such research at USGS must meet NEHRP objectives. The most recent charges for USGS are outlined in the Draft of...

In a desert area, it is difficult to couple geophones with dry sands. A low and depression velocity layer can seriously attenuate high frequency components of seismic data. Therefore, resolution and signal-to-noise (S/N) ratio of seismic data deteriorate. To enhance resolution and S/N ratio of seismic data, we designed a coupling compensatory inverse filter by using the single trace...

The study of foraging ecology plays a central role in our understanding of animal populations and natural communities, and can also provide information necessary for the effective conservation of rare or endangered species. Sea otter researchers are interested in foraging ecology for many different reasons, but for heuristic purposes we identify three general types of research questions...

The coastal infrastructure of the southern greater Los Angeles metropolitan area would be profoundly affected by a large tsunami. Submarine slope failures and active faults, either of which could have generated a tsunami, are known on the shelf and slope near Long Beach. Large slope failures are present on the San Pedro Escarpment and on the basin slope adjacent to the San Pedro shelf...

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Species of the family of Salmonidae occur naturally in Northern Hemisphere waters that remain clear and cool to cold in summer. For purposes of reproduction, salmonids generally behaviorally respond to the currents of streams and lakes in recently glaciated areas. For feeding and maturation, many larger species migrate into existing systems of large lakes, seas, and oceans. The...

There are few well-documented, general ecological principles that can be applied to pressing environmental issues. When they discuss them at all, ecologists often disagree about the relative importance of different aspects of the science's original and still important issues. It may be that the sum of ecological science is not open to universal statements because of the wide range of

The bioavailability of chemicals to earthworms can be modified dramatically by soil physical/chemical characteristics, yet expressing exposure as total chemical concentrations does not address this problem. In order to understand the effects of modifying factors on bioavailability, one must measure and express chemical bioavailability to earthworms in a consistent, logical manner. This...

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An Engineered Geothermal System (EGS) field experiment will be conducted to hydraulically stimulate injection well 34-9RD2, located on the east flank of the Coso geothermal reservoir, with the objective of increasing the injection rate of this well to 750 gpm at a wellhead pressure of 100 psi or less. The stimulation of this well is expected to create hydraulic communication with the...

The permanent 16-station network of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14 temporary instruments deployed in connection with the DOE Enhanced Geothermal Systems (EGS) Project, provides high-quality microearthquake (MEQ) recordings that are well suited to monitoring a producing geothermal area. We are currently using these data to