Publications
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Time-averaged discharge rate of subaerial lava at Kīlauea Volcano, Hawai‘i, measured from TanDEM-X interferometry: Implications for magma supply and storage during 2011-2013 Time-averaged discharge rate of subaerial lava at Kīlauea Volcano, Hawai‘i, measured from TanDEM-X interferometry: Implications for magma supply and storage during 2011-2013
Differencing digital elevation models (DEMs) derived from TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) synthetic aperture radar imagery provides a measurement of elevation change over time. On the East Rift Zone (EZR) of Kīlauea Volcano, Hawai‘i, the effusion of lava causes changes in topography. When these elevation changes are summed over the area of an active lava...
Authors
Michael P. Poland
Emplacement and erosive effects of the south Kasei Valles lava on Mars Emplacement and erosive effects of the south Kasei Valles lava on Mars
Although it has generally been accepted that the Martian outflow channels were carved by floods of water, observations of large channels on Venus and Mercury demonstrate that lava flows can cause substantial erosion. Recent observations of large lava flows within outflow channels on Mars have revived discussion of the hypothesis that the Martian channels are also produced by lava. An...
Authors
Colin M. Dundas, Laszlo P. Keszthelyi
Drift issues of tall buildings during the March 11, 2011 M9.0 Tohoku earthquake, Japan - Implications Drift issues of tall buildings during the March 11, 2011 M9.0 Tohoku earthquake, Japan - Implications
One of the most significant effects of the M9.0 Tohoku, Japan earthquake of March 11, 2011 is the now well-known long duration (>10 minutes) shaking of buildings in Japan – particularly those in Tokyo (~350-375 km from the epicenter) and in places as far as Osaka (~770 km from the epicenter). Although none collapsed, the strong shaking caused many tall buildings not to be functional for...
Authors
Mehmet Çelebi, Izuru Okawa
Comparison of NGA-West2 directivity models Comparison of NGA-West2 directivity models
Five directivity models have been developed based on data from the NGA-West2 database and based on numerical simulations of large strike-slip and reverse-slip earthquakes. All models avoid the use of normalized rupture dimension, enabling them to scale up to the largest earthquakes in a physically reasonable way. Four of the five models are explicitly “narrow-band” (in which the effect...
Authors
Paul A. Spudich, Badie Rowshandel, Shrey Shahi, Jack W. Baker, Brian S-J Chiou
Adding fling effects to processed ground‐motion time histories Adding fling effects to processed ground‐motion time histories
Fling is the engineering term for the effects of the permanent tectonic offset, caused by a rupturing fault in the recorded ground motions near the fault. It is expressed by a one‐sided pulse in ground velocity and a nonzero final displacement at the end of shaking. Standard processing of earthquake time histories removes some of the fling effects that may be required for engineering...
Authors
Ronnie Kamai, Norman A. Abrahamson, Robert Graves
A depth-averaged debris-flow model that includes the effects of evolving dilatancy. I. Physical basis A depth-averaged debris-flow model that includes the effects of evolving dilatancy. I. Physical basis
To simulate debris-flow behaviour from initiation to deposition, we derive a depth-averaged, two-phase model that combines concepts of critical-state soil mechanics, grain-flow mechanics and fluid mechanics. The model's balance equations describe coupled evolution of the solid volume fraction, m, basal pore-fluid pressure, flow thickness and two components of flow velocity. Basal...
Authors
Richard M. Iverson, David L. George
NGA-West2 Research Project NGA-West2 Research Project
The NGA-West2 project is a large multidisciplinary, multi-year research program on the Next Generation Attenuation (NGA) models for shallow crustal earthquakes in active tectonic regions. The research project has been coordinated by the Pacific Earthquake Engineering Research Center (PEER), with extensive technical interactions among many individuals and organizations. NGA-West2...
Authors
Yousef Bozorgnia, Norman A. Abrahamson, Linda Al Atik, Timothy D. Ancheta, Gail M. Atkinson, Jack W. Baker, Annemarie S. Baltay Sundstrom, David M. Boore, Kenneth W. Campbell, Brian S.J. Chiou, Robert B. Darragh, Steve Day, Jennifer Donahue, Robert W. Graves, Nick Gregor, Thomas C. Hanks, I. M. Idriss, Ronnie Kamai, Tadahiro Kishida, Albert Kottke, Stephen A. Mahin, Sanaz Rezaeian, Badie Rowshandel, Emel Seyhan, Shrey Shahi, Tom Shantz, Walter Silva, Paul A. Spudich, Jonathan P. Stewart, Jennie Watson-Lamprey, Kathryn Wooddell, Robert Youngs
High manganese concentrations in rocks at Gale crater, Mars High manganese concentrations in rocks at Gale crater, Mars
The surface of Mars has long been considered a relatively oxidizing environment, an idea supported by the abundance of ferric iron phases observed there. However, compared to iron, manganese is sensitive only to high redox potential oxidants, and when concentrated in rocks, it provides a more specific redox indicator of aqueous environments. Observations from the ChemCam instrument on...
Authors
Nina L. Lanza, Woodward W. Fischer, Roger C. Wiens, John P. Grotzinger, Ann M. Ollila, Ryan B. Anderson, Benton C. Clark, Ralf Gellert, Nicolas Mangold, Sylvestre Maurice, Stéphane Le Mouélic, Marion Nachon, Mariek E. Schmidt, Jeffrey Berger, Samuel M. Clegg, Olivier Forni, Craig Hardgrove, Noureddine Melikechi, Horton E. Newsom, Violaine Sautter
Contrasting volcanism in Hawaiʻi and the Galápagos Contrasting volcanism in Hawaiʻi and the Galápagos
The archipelagos of Hawai‘i and the Galápagos originated at mantle hotspots, yet the volcanoes that make up the island chains differ in most respects. Some of the most important differences include the dynamics of magma supply, characteristics of magma storage and transport, morphology, and compositional and structural evolution. Of particular significance in the Galápagos is the lack of...
Authors
Michael P. Poland, Karen S. Harpp, Eric Mittelstaedt, Noemi d’Ozouville, David W. Graham
Sulfur isotope fractionation between fluid and andesitic melt: An experimental study Sulfur isotope fractionation between fluid and andesitic melt: An experimental study
Glasses produced from decompression experiments conducted by Fiege et al. (2014a) were used to investigate the fractionation of sulfur isotopes between fluid and andesitic melt upon magma degassing. Starting materials were synthetic glasses with a composition close to a Krakatau dacitic andesite. The glasses contained 4.55–7.95 wt% H2O, ∼140 to 2700 ppm sulfur (S), and 0–1000 ppm...
Authors
Adrian Fiege, Francois Holtz, Nobumichi Shimizu, Charlie Mandeville, Harald Behrens, Jaayke L. Knipping
SAFRR tsunami scenario: Impacts on California ecosystems, species, marine natural resources, and fisheries SAFRR tsunami scenario: Impacts on California ecosystems, species, marine natural resources, and fisheries
We evaluate the effects of the SAFRR Tsunami Scenario on California’s ecosystems, species, natural resources, and fisheries. We discuss mitigation and preparedness approaches that can be useful in Tsunami planning. The chapter provides an introduction to the role of ecosystems and natural resources in tsunami events (Section 1). A separate section focuses on specific impacts of the SAFRR...
Authors
Deborah Brosnan, Anne Wein, Rick Wilson
Imaging P and S attenuation in the Sacramento-San Joaquin Delta region, northern California Imaging P and S attenuation in the Sacramento-San Joaquin Delta region, northern California
We obtain 3-D Qp and Qs models for the Delta region of the Sacramento and San Joaquin Rivers, a large fluvial-agricultural portion of the Great Valley located between the Sierra Nevada batholith and the San Francisco Bay - Coast Ranges region of active faulting. Path attenuation t* values have been obtained for P and S data from 124 distributed earthquakes, with a longer variable window...
Authors
Donna Eberhart-Phillips, Clifford Thurber, Jon Peter B. Fletcher