Publications

The South American arc extends over 7,000 km, from the Chilean triple junction offshore of southern Chile to its intersection with the Panama fracture zone, offshore the southern coast of Panama in Central America. It marks the plate boundary between the subducting Nazca plate and the South America plate, where the oceanic crust and lithosphere of the Nazca plate begin their decent into...

This map shows details of Japan and vicinity not visible in an earlier publication, U.S. Geological Survey Scientific Investigations Map 3064. Japan and its island possessions lie across four major tectonic plates: Pacific plate, North America plate; Eurasia plate; and Philippine Sea plate. The Pacific plate is subducted into the mantle, beneath Hokkaido and northern Honshu, along the...

This atlas presents an up-to-date map compilation of the geological and geophysical observations that underpin interpretations of active, surface-deforming faults in the Puget Lowland, Washington. Shallow lowland faults are mapped where observations of deformation from paleoseismic, seismic-reflection, and potential-field investigations converge. Together, results from these studies...

The postseismic relaxation (postseismic displacement less displacement that would have occurred at the preseismic rate) measured by GPS and leveling following the 1989 MS7.1 Loma Prieta earthquake is reexamined. The temporal dependence of the relaxation over the first 1200 days postseismic is well described by 1 − e−t/τ, where τ = 414 ± 92 days. (Quoted uncertainties are standard...

[1] The similarity of seismograms recorded by two seismic stations demonstrate that the 31 October 2007 moment magnitude M5.4 Alum Rock earthquake is a repeat of a 1955 ML5.5 earthquake. Both occurred on Oppenheimer et al.'s (1990) Zone V “stuck patch” on the central Calaveras fault, providing new support for their model of Calaveras fault earthquake activity. We suggest that Zone V...

We study the source process of the Kīholo Bay earthquake (MW 6.7), which occurred beneath the northwest part of the Island of Hawai‘i on 15 October 2006, and static stress drops of small earthquakes that occurred in 2006 and 2007 around the main shock including aftershocks. We relocate the aftershocks to determine the fault plane from the two nodal planes. The relocated aftershocks...

Present‐day accumulation in the north polar layered deposits (NPLD) is thought to occur via deposition on the north polar residual cap. Understanding current mass balance in relation to current climate would provide insight into the climatic record of the NPLD. To constrain processes and rates of NPLD resurfacing, a search for craters was conducted using images from the Mars...

We investigate a spectrum-based technique to identify the style of active volcanic eruptions on Jupiter's moon Io. Thermal remote sensing of Io has had to rely primarily on low-spatial-resolution data, similar to low-spatial-resolution satellite data applied to detecting and charting the temporal evolution of terrestrial hot spots. These terrestrial analyses use data from sensors...

No abstract available.

In response to a request by the National Oceanic and Atmospheric Administration (NOAA) for computing tsunami propagations in the western Pacific, Eric Geist asked Willie Lee for assistance in providing parameters of earthquakes which may be future tsunami sources. The U.S. Geological Survey (USGS) Tsunami Source Working Group (TSWG) was initiated in August 2005. An ad hoc group of...

Earthquake engineering practice is increasingly using nonlinear response history analysis (RHA) to demonstrate performance of structures. This rigorous method of analysis requires selection and scaling of ground motions appropriate to design hazard levels. Presented herein is a modal-pushover-based scaling (MPS) method to scale ground motions for use in nonlinear RHA of buildings and...

Recent multibeam surveys along the continental slope and rise off southeast New England has enabled a detailed morphological analysis of the Block composite landslide. This landslide consists of at least three large debris lobes resting on a gradient less than 0.5 °. The slide took place on gradients of between 1 ° and 5 ° in Quaternary sediments likely deposited at the time of low sea...