Publications
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Magma-ice-sediment interactions and the origin of lava/hyaloclastite sequences in the Síða formation, South Iceland
Products of subglacial volcanism can illuminate reconstructions of paleo-environmental conditions on both local and regional scales. Competing interpretations of Pleistocene conditions in south Iceland have been proposed based on an extensive sequence of repeating lava-and-hyaloclastite deposits in the Síða district. We propose here a new eruptive model and refine the glacial environment during er
Authors
Tenley J. Banik, Paul J. Wallace, Ármann Höskuldsson, Calvin F. Miller, Charles R. Bacon, David J. Furbish
Why the New Madrid earthquakes are M 7–8 and the Charleston earthquake is ∼M 7
Estimates of magnitudes of large historical earthquakes are an essential input to and can seriously affect seismic‐hazard estimates. The earthquake‐intensity observations, modified Mercalli intensities (MMI), and assigned magnitudes Mof the 1811–1812 New Madrid events have been reinterpreted several times in the last decade and have been a source of controversy in making seismic‐hazard estimates i
Authors
Chris H. Cramer, Oliver S. Boyd
Cogenetic late Pleistocene rhyolite and cumulate diorites from Augustine Volcano revealed by SIMS 238U-230Th dating of zircon, and implications for silicic magma generation by extraction from mush
Augustine Volcano, a frequently active andesitic island stratocone, erupted a late Pleistocene rhyolite pumice fall that is temporally linked through zircon geochronology to cumulate dioritic blocks brought to the surface in Augustine's 2006 eruption. Zircon from the rhyolite yield a 238U-230Th age of ∼25 ka for their unpolished rims, and their interiors yield a bimodal age populations at ∼26 ka a
Authors
Michelle L. Coombs, Jorge A. Vazquez
Late Holocene slip rate and ages of prehistoric earthquakes along the Maacama Fault near Willits, Mendocino County, northern California
The Maacama fault is the northward continuation of the Hayward–Rodgers Creek fault system and creeps at a rate of 5.7±0.1 mm/yr (averaged over the last 20 years) in Willits, California. Our paleoseismic studies at Haehl Creek suggest that the Maacama fault has produced infrequent large earthquakes in addition to creep. Fault terminations observed in several excavations provide evidence that a pre
Authors
Carol S. Prentice, Martin C. Larsen, Harvey M. Kelsey, Judith Zachariasen
Volcanology: Lessons learned from Synthetic Aperture Radar imagery
Twenty years of continuous Earth observation by satellite SAR have resulted in numerous new insights into active volcanism, including a better understanding of subsurface magma storage and transport, deposition of volcanic materials on the surface, and the structure and development of volcanic edifices. This massive archive of data has resulted in fundamental leaps in our understanding of how volc
Authors
Virginie Pinel, Michael P. Poland, Andy Hooper
Estimating the volcanic emission rate and atmospheric lifetime of SO2 from space: a case study for Kīlauea volcano, Hawai'i
We present an analysis of SO2 column densities derived from GOME-2 satellite measurements for the Kīlauea volcano (Hawai`i) for 2007–2012. During a period of enhanced degassing activity in March–November 2008, monthly mean SO2 emission rates and effective SO2 lifetimes are determined simultaneously from the observed downwind plume evolution and meteorological wind fields, without further model inp
Authors
Steffen Beirle, Christoph Hörmann, Malouse Penning de Vries, Stefan Dörner, Christoph Kern, Thomas Wagner
Eruptions at Lone Star geyser, Yellowstone National Park, USA: 2. Constraints on subsurface dynamics
We use seismic, tilt, lidar, thermal, and gravity data from 32 consecutive eruption cycles of Lone Star geyser in Yellowstone National Park to identify key subsurface processes throughout the geyser's eruption cycle. Previously, we described measurements and analyses associated with the geyser's erupting jet dynamics. Here we show that seismicity is dominated by hydrothermal tremor (~5–40 Hz) attr
Authors
Jean Vandemeulebrouck, Robert A. Sohn, Maxwell L. Rudolph, Shaul Hurwitz, Michael Manga, Malcolm J.S. Johnston, S. Adam Soule, Darcy McPhee, Jonathan M. G. Glen, Leif Karlstrom, Fred Murphy
Using the USGS Seismic Risk Web Application to estimate aftershock damage
The U.S. Geological Survey (USGS) Engineering Risk Assessment Project has developed the Seismic Risk Web Application to combine earthquake hazard and structural fragility information in order to calculate the risk of earthquake damage to structures. Enabling users to incorporate their own hazard and fragility information into the calculations will make it possible to quantify (in near real-time) t
Authors
Sean M. McGowan, Nicolas Luco
Metrics for comparing dynamic earthquake rupture simulations
Earthquakes are complex events that involve a myriad of interactions among multiple geologic features and processes. One of the tools that is available to assist with their study is computer simulation, particularly dynamic rupture simulation. A dynamic rupture simulation is a numerical model of the physical processes that occur during an earthquake. Starting with the fault geometry, friction cons
Authors
Michael Barall, Ruth A. Harris
Seismic instrumentation plan for the Hawaiian Volcano Observatory
The seismic network operated by the U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) is the main source of authoritative data for reporting earthquakes in the State of Hawaii, including those that occur on the State’s six active volcanoes (Kīlauea, Mauna Loa, Hualālai, Mauna Kea, Haleakalā, Lō‘ihi). Of these volcanoes, Kīlauea and Mauna Loa are considered “very high threat” in a report
Authors
Weston A. Thelen
Investigation of the high-frequency attenuation parameter, κ (kappa), from aftershocks of the 2010 Mw 8.8 Maule, Chile earthquake
The Bío Bío region of Chile experienced a vigorous aftershock sequence following the 2010 February 27 Mw 8.8 Maule earthquake. The immediate aftershock sequence was captured by two temporary seismic deployments: the Quake Catcher Network Rapid Aftershock Mobilization Program (QCN RAMP) and the Incorporated Research Institutions for Seismology CHile Aftershock Mobilization Program (IRIS CHAMP). Her
Authors
Corrie Neighbors, E. J. Liao, Elizabeth S. Cochran, G. J. Funning, A. I. Chung, J. F. Lawrence, C. M. Christensen, M. Miller, A. Belmonte, H. H. Andrés Sepulveda
A new analysis of Mars "Special Regions": findings of the Second MEPAG Special Regions Science Analysis Group (SR-SAG2)
A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understan
Authors
John D. Rummel, David W. Beaty, Melissa A. Jones, Corien Bakermans, Nadine G. Barlow, Penelope J. Boston, Vincent F. Chevrier, Benton C. Clark, Jean-Pierre P. de Vera, Raina V. Gough, John E. Hallsworth, James W. Head, Victoria J. Hipkin, Thomas L. Kieft, Alfred S. McEwen, Michael T. Mellon, Jill A. Mikucki, Wayne L. Nicholson, Christopher R. Omelon, Ronald Peterson, Eric E. Roden, Barbara Sherwood Lollar, Kenneth L. Tanaka, Donna Viola, James J. Wray