Publications
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A sight "fearfully grand": eruptions of Lassen Peak, California, 1914 to 1917
On May 22, 1915, a large explosive eruption at the summit of Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 280 miles to the east. This explosion was the most powerful in a series of eruptions during 1914–17 that were the last to occur in the Cascade Range before the 1980 eruption of Mount St. Helens, Wa
Authors
Michael A. Clynne, Robert L. Christiansen, Peter H. Stauffer, James W. Hendley, Heather A. Bleick
The California Volcano Observatory: Monitoring the state's restless volcanoes
Volcanic eruptions happen in the State of California about as frequently as the largest earthquakes on the San Andreas Fault Zone. At least 10 eruptions have taken place in California in the past 1,000 years—most recently at Lassen Peak in Lassen Volcanic National Park (1914 to 1917) in the northern part of the State—and future volcanic eruptions are inevitable. The U.S. Geological Survey Californ
Authors
Wendy K. Stovall, Mae Marcaida, Margaret T. Mangan
Small crater modification on Meridiani Planum and implications for erosion rates and climate change on Mars
A morphometric and morphologic catalog of ~100 small craters imaged by the Opportunity rover over the 33.5 km traverse between Eagle and Endeavour craters on Meridiani Planum shows craters in six stages of degradation that range from fresh and blocky to eroded and shallow depressions ringed by planed off rim blocks. The age of each morphologic class from <50–200 ka to ~20 Ma has been determined fr
Authors
M.P. Golombek, N.H. Warner, V. Ganti, M.P. Lamb, T. J. Parker, Robin L. Fergason, R. Sullivan
Gravity changes and deformation at Kīlauea Volcano, Hawaii, associated with summit eruptive activity, 2009-2012
Analysis of microgravity and surface displacement data collected at the summit of Kīlauea Volcano, Hawaii (USA), between December 2009 and November 2012 suggests a net mass accumulation at ~1.5 km depth beneath the northeast margin of Halema‘uma‘u Crater, within Kīlauea Caldera. Although residual gravity increases and decreases are accompanied by periods of uplift and subsidence of the surface, re
Authors
Marco Bagnardi, Michael P. Poland, Daniele Carbone, Scott Baker, Maurizio Battaglia, Falk Amelung
Localized rejuvenation of a crystal mush recorded in zircon temporal and compositional variation at the Lassen Volcanic Center, northern California
Zircon ages and trace element compositions from recent silicic eruptions in the Lassen Volcanic Center (LVC) allow for an evaluation of the timing and conditions of rejuvenation (reheating and mobilization of crystals) within the LVC magmatic system. The LVC is the southernmost active Cascade volcano and, prior to the 1980 eruption of Mount St. Helens, was the site of the only eruption in the Casc
Authors
Erik W. Klemetti, Michael A. Clynne
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
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