Publications

The method for estimating the site effect on ground motion specified by Borcherdt (1994a, 1994b) is briefly introduced in the paper. This method and the detail geological data and site classification data in San Francisco bay area of California, the United States, are applied to simulate the influenced field of scenario earthquake by GIS technology, and the software for simulating has been drawn u

The Mars Pathfinder (MPF) spacecraft landed on relatively young (late Hesperian-early Amazonian; 3.1-0.7 Ga) plains in Chryse Planitia near the mouth of Ares Vallis. Images returned from the spacecraft reveal a complex landscape of ridges and troughs, large hills and crater rims, rocks and boulders of various sizes and shapes, and surficial deposits, indicating a complex, multistage geologic histo

Rapid (3-5 minutes) generation of maps of instrumental ground-motion and shaking intensity is accomplished through advances in real-time seismographic data acquisition combined with newly developed relationships between recorded ground-motion parameters and expected shaking intensity values. Estimation of shaking over the entire regional extent of southern California is obtained by the spatial int

Landslides, worldwide and in the United States, are arguably the most costly natural hazard. Substantial landslide information is available, but much of it remains underutilized, as a disconnect exists among geologists, decision makers, and the public. The lack of a national landslide insurance policy exacerbates this situation and promotes litigation as the principal recourse for recouping landsl

Two vastly different phenomena, impact and salt diapirism, have been proposed for the origin of Upheaval Dome, a spectacular scenic feature in southeast Utah. Detailed geologic mapping and seismic refraction data indicate that the dome originated by collapse of a transient cavity formed by impact. Evidence is as follows: (1) sedimentary strata in the center of the structure are pervasively imbrica

A late Hesperian smooth plains deposit on Mars interpreted as a debris flow extends more than 2000 km from Hydraotes Chaos, through Simud and Tiu Valles, and into Chryse Planitia. The Simud/Tiu deposit widens out to >1000 km and embays streamlined landforms and knobs made up of sedimentary and perhaps volcanic deposits that were carved by earlier channeling activity. Morphologic features of the Si

The Imager for Mars Pathfinder returned over 16,000 high-quality images from the surface of Mars. The camera was well-calibrated in the laboratory, with <5% radiometric uncertainty. The photometric properties of two radiometric targets were also measured with 3% uncertainty. Several data sets acquired during the cruise and on Mars confirm that the system operated nominally throughout the course of

Studies of Yucca Mountain, Nevada, as a potential geologic nuclear-waste repository began in the late 1970s and continued to 1988 when the U. S. Nuclear Regulatory Commission determined that the quality assurance (QA) programs in place were not adequate and demanded restructuring to a new QA program. The new QA program was accepted in 1989, but many activities did not resume until new procedures w

Following the 1994 Mw=6.7 Northridge earthquake, a 65‐km‐long, north‐south array of 11 geodetic monuments was established across the rupture. The array was surveyed with GPS ten times in the 4.25 yr after the earthquake. Although there is evidence for modest nonlinear postseismic relaxation in the first few weeks after the Northridge earthquake, the deformation in the subsequent four years can be

A linear array of 15 geodetic monuments was installed in 1993 across the rupture zone of the 1964 Alaska earthquake (Mw = 9.2). The array extends from Middleton Island (at the edge of the continental shelf and 80 km from the Alaska‐Aleutian trench) to north of Palmer, Alaska (380 km from the trench), in the approximate direction of Pacific‐North American plate convergence (N15.5°W). The array was

We discuss three interconnected processes that occur during continental compression and extension: delamination of the lower crust and sub-crustal lithosphere, escape tectonics (i.e., lateral crustal flow), and crustal uplift. We combine calculations of lithospheric viscosity–depth curves with geologic observations and seismic images of the deep crust to infer the mechanisms controlling these proc

No abstract avaialable.