Publications
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Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone Caldera
Characterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area (OPTA) and the 0.25 km2 Solfatara Plateau Thermal Area (SPTA). Conductive h
Authors
Shaul Hurwitz, Robert Harris, Cynthia Anne Werner, Fred Murphy
The 2009 eruption of Redoubt Volcano, Alaska
Redoubt Volcano, an ice-covered stratovolcano on the west side of Cook Inlet, erupted in March 2009 after several months of escalating unrest. The 2009 eruption of Redoubt Volcano shares many similarities with eruptions documented most recently at Redoubt in 1966–68 and 1989–90. In each case, the eruptive phase lasted several months, consisted of multiple ashproducing explosions, produced andesiti
Authors
Katharine F. Bull, Cheryl Cameron, Michelle L. Coombs, Angie Diefenbach, Taryn Lopez, Steve McNutt, Christina A. Neal, Allison Payne, John A. Power, David J. Schneider, William E. Scott, Seth Snedigar, Glenn Thompson, Kristi L. Wallace, Christopher F. Waythomas, Peter Webley, Cynthia A. Werner
Implications of NGA for NEHRP site coefficients
Three proposals are provided to update tables 11.4-1 and 11.4-2 of Minimum Design Loads for Buildings and Other Structures (7-10), by the American Society of Civil Engineers (2010) (ASCE/SEI 7-10), with site coefficients implied directly by NGA (Next Generation Attenuation) ground motion prediction equations (GMPEs). Proposals include a recommendation to use straight-line interpolation to infer si
Authors
Roger D. Borcherdt
Laboratory triggering of stick-slip events by oscillatory loading in the presence of pore fluid with implications for physics of tectonic tremor
The physical mechanism by which the low-frequency earthquakes (LFEs) that make up portions of tectonic (also called non-volcanic) tremor are created is poorly understood. In many areas of the world, tectonic tremor and LFEs appear to be strongly tidally modulated, whereas ordinary earthquakes are not. Anomalous seismic wave speeds, interpreted as high pore fluid pressure, have been observed in reg
Authors
Noel M. Bartlow, David A. Lockner, Nicholas M. Beeler
Laboratory observations of fault strength in response to changes in normal stress
Changes in fault normal stress can either inhibit or promote rupture propagation, depending on the fault geometry and on how fault shear strength varies in response to the normal stress change. A better understanding of this dependence will lead to improved earthquake simulation techniques, and ultimately, improved earthquake hazard mitigation efforts. We present the results of new laboratory expe
Authors
Brian D. Kilgore, Julian Lozos, Nicholas M. Beeler, David Oglesby
Should ground-motion records be rotated to fault-normal/parallel or maximum direction for response history analysis of buildings?
In the United States, regulatory seismic codes (for example, California Building Code) require at least two sets of horizontal ground-motion components for three-dimensional (3D) response history analysis (RHA) of building structures. For sites within 5 kilometers (3.1 miles) of an active fault, these records should be rotated to fault-normal and fault-parallel (FN/FP) directions, and two RHAs sho
Authors
Juan C. Reyes, Erol Kalkan
Mars global digital dune database: MC-30
The Mars Global Digital Dune Database (MGD3) provides data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey Open-File Reports. The first report (Hayward and others, 2007) included dune fields from lat 65° N. to 65° S. (http://pubs.usgs.gov/of/2007/1158/). The secon
Authors
R.K. Hayward, L.K. Fenton, T.N. Titus, A. Colaprete, P. R. Christensen
Advanced earthquake monitoring system for U.S. Department of Veterans Affairs medical buildings--instrumentation
In collaboration with the U.S. Department of Veterans Affairs (VA), the National Strong Motion Project (NSMP; http://nsmp.wr.usgs.gov/) of the U.S. Geological Survey has been installing sophisticated seismic systems that will monitor the structural integrity of 28 VA hospital buildings located in seismically active regions of the conterminous United States, Alaska, and Puerto Rico during earthquak
Authors
Erol Kalkan, Krishna Banga, Hasan S. Ulusoy, Jon Peter B. Fletcher, William S. Leith, Shahneam Reza, Timothy Cheng
Earthquake recurrence models fail when earthquakes fail to reset the stress field
Parkfield's regularly occurring M6 mainshocks, about every 25 years, have over two decades stoked seismologists' hopes to successfully predict an earthquake of significant size. However, with the longest known inter-event time of 38 years, the latest M6 in the series (28 Sep 2004) did not conform to any of the applied forecast models, questioning once more the predictability of earthquakes in gene
Authors
Thessa Tormann, Stefan Wiemer, Jeanne L. Hardebeck
New "Risk-Targeted" Seismic Maps Introduced into Building Codes
Throughout most municipalities of the United States, structural engineers design new buildings using the U.S.-focused International Building Code (IBC). Updated editions of the IBC are published every 3 years. The latest edition (2012) contains new "risk-targeted maximum considered earthquake" (MCER) ground motion maps, which are enabling engineers to incorporate a more consistent and better defin
Authors
Nicholas Luco, B. Garrett, J. Hayes
Earthquake ground motion
Most of the effort in seismic design of buildings and other structures is focused on structural design. This chapter addresses another key aspect of the design process—characterization of earthquake ground motion. Section 3.1 describes the basis of the earthquake ground motion maps in the Provisions and in ASCE 7. Section 3.2 has examples for the determination of ground motion parameters and spect
Authors
Nicolas Luco, Michael Valley, C.B. Crouse
Revelations from ambient shaking data of a recently instrumented unique building at MIT campus
A state-of-the-art seismic monitoring system comprising 36 accelerometers and a data-logger with real-time capability was recently installed at Building 54 on the campus of the Massachusetts Institute of Technology [MIT], Cambridge, Massachusetts. The system is designed to record translational, torsional and rocking motions, and to facilitate computation of drift between select pairs of stories. T
Authors
Mehmet Çelebi, N. Toksoz, O. Buyukozturk