USGS PCMSC News

"Slip rate on the San Diego trough fault zone, inner California Borderland, and the 1986 Oceanside earthquake swarm revisited" by USGS geologists Holly Ryan, James Conrad, and Mary McGann and their colleague Charles Paull of the Monterey Bay Aquarium Research Institute was published in the December 2012 issue of the Bulletin of the Seismological Society of America. The authors determined a slip rate for the San Diego trough fault zone—the first slip rate determined for a fault entirely offshore—that will improve the accuracy of the new Uniform California Earthquake Rupture Forecast. They also present new seismic-reflection data showing that the fault extends further to the north, where it may join with the San Pedro Basin fault, making it one of the longest and thus potentially most hazardous faults offshore of California. (Holly Ryan, Menlo Park, CA, 650-329-5487) [Download 2.7 MB PDF, or view the BSSA Online Version

New journal article: Aleutian Tectonics and Glaciation Affect Interplate Coupling, Potential for Tsunamigenic Earthquakes

"Influence of the Amlia fracture zone on the evolution of the Aleutian Terrace forearc basin, central Aleutian subduction zone" by USGS geologists Holly Ryan, Amy Draut, and David Scholl (emeritus) and their colleague Katie Keranen of the University of Oklahoma was published in the December 2012 issue of Geosphere. The authors use seismic-reflection data to describe forearc basin evolution and relate it to areas of coupling on the Aleutian megathrust that can generate great earthquakes. Both the subduction of the Amlia fracture zone and a mid-Pleistocene increase in glaciation influenced plate coupling. This study has implications for the generation of massive tsunamis from both earthquakes and earthquake-triggered large-scale failures of the Aleutian Ridge. (Holly Ryan, Menlo Park, CA, 650-329-5487) [View the Geophere Online Version]

Evaluating Effects of San Clemente Dam Removal on Carmel River in California—Lessons from Elwha River Dam Removals in Washington

USGS geologists Amy Draut and Jonathan Warrick were invited presenters at the San Clemente Dam Removal Studies Workshop held November 29–30, 2012, at the NOAA Southwest Fisheries Science Center in Santa Cruz, California. The goal of the workshop was to develop a strategic research plan to evaluate changes to California's Carmel River resulting from the removal of San Clemente Dam. Amy and Jon presented lessons learned from river and coastal investigations during the ongoing Elwha River Restoration Project in Washington, the largest dam removal in U.S. history. More information about the Elwha River project can be found at http://www.usgs.gov/elwha. (Jonathan Warrick, Santa Cruz, CA, 831-460-7569)

USGS geologist David Rubin spoke on "Morphologic and dynamic similarities between polygonal dunes on Mars and interference ripples on Earth" on December 4, 2012, at the American Geophysical Union Fall Meeting in San Francisco, CA. Rubin and his colleague Claire Newman, of Ashima Research in Pasadena, CA, observed that dunes in some Martian craters have shapes similar to ripples on Earth, including relatively symmetrical cross-sections and crests that form distinctive polygonal patterns. On Earth, one can observe such bedforms produced by complicated multidirectional flows of water. Rubin and Newman hypothesize that the dune patterns on Mars formed by similar multidirectional flows of wind. The work was funded by NASA Mars Data Analysis Program. Rubin is also a member of the 2-year Mars Science Laboratory team exploring Mars with the rover Curiosity. (David Rubin, Santa Cruz, CA, 831-460-7536)

At the request of scientists from the Korea Institute of Geoscience and Mineral Resources (KIGAM), USGS geologist James Hein arranged tours of USGS facilities in Menlo Park and Santa Cruz, CA, on December 6, 2012. The visitors, including KIGAM President Dr. Hyo-Sook Lee, were in the area for the AGU Fall Meeting in San Francisco. Hosted by USGS geophysicist (emeritus) Jon Childs in Menlo Park and Hein in Santa Cruz, they were introduced to a range of USGS studies, including microbiology, radiometric dating, the Seismic Network, deep-sea mineral investigations, and more. Hein sent word of their interest to the office of USGS Director Marcia McNutt, who met with KIGAM President Dr. Lee on December 5. (James Hein, Santa Cruz, CA, 831-460-7419)

USGS Pacific Coastal and Marine Science Center (PCMSC) Director Bob Rosenbauer hosted a meeting with University of California, Santa Cruz Dean of Physical and Biological Sciences Paul Koch, along with Earth and Planetary Sciences Department Chair Quentin Williams and Ocean Sciences Chair Jonathan Zehr, on Wednesday afternoon, 12/12/12. Participants, including scientists who lead various PCMSC projects, discussed areas in which the two organizations could increase collaborative research and share expertise and lab facilities. (Bob Rosenbauer, Santa CA, 831-460-7401)

USGS technicians and scientists at the Pacific Coastal and Marine Science Center in Santa Cruz, CA, were trained to use a newly acquired lidar scanner during a multiday workshop (week of 12/10/12) organized by Deputy Center Director George Tate and geographer Joshua Logan. Using laser light to measure distances, lidar scanners produce highly accurate 3D maps of the surrounding environment. Workshop activities included an introduction to the scanner and its software, scanning terrain at nearby Younger Lagoon for comparison with previous surveys, and instruction on post-processing, data flow, and data management. The center will deploy the new scanner in 2013, likely at the Elwha River in Washington as part of USGS studies of landscape change caused by the removal of two large dams. (George Tate, Santa Cruz, CA, 831-460-7484)

Oceanographer Andy O'Neill joined the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center in Santa Cruz, California, in August 2012. She is assisting Patrick Barnard and Li Erikson with the development of the Coastal Storm Modeling System (CoSMoS) for assessing future climate-change impacts along the California coast.

Olivia Cheriton has joined the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center in Santa Cruz, California, as an oceanographer in support of several projects: Pacific Coral Reef Geology and Oceanography, National Seafloor Mapping and Benthic Habitat Studies, and Climate Change Impacts to the U.S. Pacific and Arctic Coasts.