Robert B. Smith

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[1] Seismicity of the Yellowstone volcanic field, northwest Wyoming, is characterized by swarms of earthquakes (M C < 3) within the 0.64-Myr-old, 70 km by 40 km Yellowstone caldera and between the caldera and the eastern end of the 44-km-long rupture of the M S 7.5 1959 Hebgen Lake, Montana, earthquake. Over 3000 earthquakes with M C < 5 were recorded(More)
The 3-D P-wave velocity and P-to S-wave velocity ratio structure of the Yellowstone volcanic field, Wyoming, has been determined from local earthquake tomography using new data from the permanent Yellowstone seismic network. We selected 3374 local earthquakes between 1995 and 2001 to invert for the 3-D P-wave velocity (V p) and P-wave to S-wave velocity(More)
[1] The movement of the lithosphere over a stationary mantle magmatic source, often thought to be a mantle plume, explains key features of the 16 Ma Yellowstone–Snake River Plain volcanic system. However, the seismic signature of a Yellowstone plume has remained elusive because of the lack of adequate data. We employ new teleseismic P and S wave traveltime(More)
[1] Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations.(More)
  • Michael S Zhdanov, Robert B Smith, Alexander Gribenko, Martin Cuma, Marie Green, R B Smith +3 others
  • 2011
[1] Interpretation of the EarthScope MT (magnetotelluric) data requires the development of a large‐scale inversion method which can address two common problems of 3D MT inversion: computational time and memory requirements. We have developed an efficient method of 3D MT inversion based on an IE (integral equation) formulation of the MT forward modeling(More)
The Yellowstone caldera began a rapid episode of ground uplift in mid-2004, revealed by Global Positioning System and interferometric synthetic aperture radar measurements, at rates up to 7 centimeters per year, which is over three times faster than previously observed inflation rates. Source modeling of the deformation data suggests an expanding volcanic(More)
Due to the increasing disparity between processor and main memory system cycle times, many computer systems are now incorporating two levels fo cache memory. Several studies have been done on the design and performance of second level caches, including [3] and [20]. It certainly can and has been shown that the addition of a second level of cache enhances(More)
[1] We have found spatial variations in seismic stress indicators at the Yellowstone volcanic field, Wyoming, by examining source mechanisms of 25 years of network-recorded earthquakes, 1973–1998. Yellowstone seismicity is characterized by swarms of earthquakes (M C < 3) within the 0.64 Ma Yellowstone caldera and between the caldera and the eastern end of(More)
  • Walter J Arabasz, Robert B Smith, James C Pechmann, Kristine L Pankow, Relu Burlacu
  • 2006
The cooperative agreement identified here, combined with funding from the State of Utah, provided major support for the operation of (1) the University of Utah Seismograph Stations' (UUSS) regional and urban seismic network and (2) a regional earthquake-recording and information center on the University of Utah campus in Salt Lake City. On December 1, 2006,(More)
The Yellowstone supervolcano is one of the largest active continental silicic volcanic fields in the world. An understanding of its properties is key to enhancing our knowledge of volcanic mechanisms and corresponding risk. Using a joint local and teleseismic earthquake P-wave seismic inversion, we revealed a basaltic lower-crustal magma body that provides(More)