Publications

No abstract available.

The mechanical properties of elemental sulfur are such that the upper crust of Io cannot be primarily sulfur. For heat flows in the range 100–1000 ergs cm−2, sec−1, sulfur becomes ductile within several hundred meters of the surface and would prevent the formation of calderas with depths greater than this. However, the one caldera for which precise depth data are available is 2 km deep...

Prism-shaped single crystals of MgO(Al2O3)n spinel (n 1.1) have been compressed to significant plastic strain at a temperature of 400°C (∼0·28 TM) in controlled experiments under a superimposed hydrostatic pressure of 1·4 GPa. Compression of crystals approximately parallel to , and resulted in simple yield behaviour at axial stress differences of 1940, 3720, and 4300 MPa respectively...

No abstract available.

No abstract available.

Studies conducted in the San Francisco Bay Region (Gibbs, Fumal and Borcherdt, 1980) have shown that average shear-wave velocity can be readily tied to quantitative estimates of ground motion such as ground amplification and earthquake intensity. Furthermore, when certain physical properties of the geologic materials such as texture, hardness and fracture spacing are observed during...

This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency...

The Seismic Research Observatory (SRO) network is generating an important new data base for seismological research. The SRO systems have extended both the range and resolution of seismic measurements beyond the limits of conventional seismographs and the data are recorded in digital format making it convenient to automate processing and analysis. The SRO network now comprises 12 stations...

An exploratory trench was excavated across the 1915 trace of the Pleasant Valley fault 60 km south of Winnemucca, Nevada, to get information on the history of recent displacements on a fault that had produced a major earthquake in historic time, and on the appearance of such a fault in a trench cut in gravels, sands and silts of an alluvial fan. The trench exposed 16 mappable sedimentary...

The seismic noise spectra presented in this report were derived from SRO and ASRO station data for the purpose of evaluating the performance of the seismic instruments. They are also useful for constructing a spectral estimate of earth noise at a quiet site based on noise samples obtained from a network of globally distributed sites. It is hoped that the spectra will be usefull for other...

A side-scan sonar survey of San Pedro shelf, California, reveals areas of mesoscale current lineations oriented approximately north-northeast in water depths of 20-25 m. Widths of sand ribbons range from 40 to 120 m and intervening erosional furrows, from 15 to 50 m. A conceptual model shows that the scale and orientation of current lineations agree with the dimensions and axial...

Variations in the concentration of total suspended particulate matter (TSM) collected 1 m above bottom, changes in vertical profiles of light transmission, and substrate textural patterns reveal a corridor for preferential sediment transport on San Pedro continental shelf, California. During the winter, this corridor, designated the preferential transport corridor (PTC), is defined by...