Publications
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Observations of volcanic tremor during January-February 2005 eruption of Mt. Veniaminof, Alaska
Mt. Veniaminof, Alaska Peninsula, is a stratovolcano with a summit ice-filled caldera containing a small intracaldera cone and active vent. From January 2 to February 21, 2005, Mt. Veniaminof erupted. The eruption was characterized by numerous small ash emissions (VEI 0 to 1) and accompanied by low-frequency earthquake activity and volcanic tremor. We have performed spectral analyses of the seismi
Authors
Slivio De Angelis, Stephen R. McNutt
Swarms of repeating long-period earthquakes at Shishaldin Volcano, Alaska, 2001-2004
During 2001–2004, a series of four periods of elevated long-period seismic activity, each lasting about 1–2 months, occurred at Shishaldin Volcano, Aleutian Islands, Alaska. The time periods are termed swarms of repeating events, reflecting an abundance of earthquakes with highly similar waveforms that indicate stable, non-destructive sources. These swarms are characterized by increased earthquak
Authors
Tanja Petersen
Analytical volcano deformation source models
Primary volcanic landforms are created by the ascent and eruption of magma. The ascending magma displaces and interacts with surrounding rock and fluids as it creates new pathways, flows through cracks or conduits, vesiculates, and accumulates in underground reservoirs. The formation of new pathways and pressure changes within existing conduits and reservoirs stress and deform the surrounding rock
Authors
Michael Lisowski
The morphology and evolution of the Stromboli 2002-2003 lava flow field--An example of a basaltic flow field emplaced on a steep slope
The use of a hand-held thermal camera during the 2002–2003 Stromboli effusive eruption proved essential in tracking the development of flow field structures and in measuring related eruption parameters, such as the number of active vents and flow lengths. The steep underlying slope on which the flow field was emplaced resulted in a characteristic flow field morphology. This comprised a proximal sh
Authors
Luigi Lodato, A. Harris, L. Spampinato, Sonia Calvari, J. Dehn, M. Patrick
Predicting and validating the motion of an ash cloud during the 2006 eruption of Mount Augustine volcano
On 11 January 2006, Mount Augustine volcano in southern Alaska began erupting after 20- year repose. The Anchorage Forecast Office of the National Weather Service (NWS) issued an advisory on 28 January for Kodiak City. On 31 January, Alaska Airlines cancelled all flights to and from Anchorage after multiple advisories from the NWS for Anchorage and the surrounding region. The Alaska Volcano Observ
Authors
Richard L. Collins, Javier Fochesatto, Kenneth Sassen, Peter W. Webley, David E. Atkinson, Kenneson G. Dean, Catherine F. Cahill, Kohei Mizutani
Extensive hydrothermal rock alteration in a low pH, steam-heated environment--Hot Springs Basin, Yellowstone National Park
No abstract available.
Authors
S. Hurwitz, J. B. Lowenstern, D. Bergfeld, C. Werner, H. Heasler, C. Jaworowski
Debris flow hazards mitigation--Mechanics, prediction, and assessment
These proceedings contain papers presented at the Fourth International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment held in Chengdu, China, September 10-13, 2007. The papers cover a wide range of topics on debris-flow science and engineering, including the factors triggering debris flows, geomorphic effects, mechanics of debris flows (e.g., rheology, fluv
Incremental assembly and prolonged consolidation of Cordilleran magma chambers--Evidence from the Southern Rocky Mountain volcanic field
Recent inference that Mesozoic Cordilleran plutons grew incrementally during >106 yr intervals, without the presence of voluminous eruptible magma at any stage, minimizes close associations with large ignimbrite calderas. Alternatively, Tertiary ignimbrites in the Rocky Mountains and elsewhere, with volumes of 1–5 × 103 km3, record multistage histories of magma accumulation, fractionation, and so
Authors
Peter W. Lipman
Pāhoehoe flow cooling, discharge, and coverage rates from thermal image chronometry
Theoretically- and empirically-derived cooling rates for active pāhoehoe lava flows show that surface cooling is controlled by conductive heat loss through a crust that is thickening with the square root of time. The model is based on a linear relationship that links log(time) with surface cooling. This predictable cooling behavior can be used assess the age of recently emplaced sheet flows from t
Authors
Jonathan Dehn, Christopher M. Hamilton, A. J. L. Harris, Richard A. Herd, M.R. James, Luigi Lodato, Andrea Steffke
Seismo-acoustic signals associated with degassing explosions recorded at Shishaldin Volcano, Alaska, 2003-2004
In summer 2003, a Chaparral Model 2 microphone was deployed at Shishaldin Volcano, Aleutian Islands, Alaska. The pressure sensor was co-located with a short-period seismometer on the volcano’s north flank at a distance of 6.62 km from the active summit vent. The seismo-acoustic data exhibit a correlation between impulsive acoustic signals (1–2 Pa) and long-period (LP, 1–2 Hz) earthquakes. Since it
Authors
T. Petersen
Lava effusion rate definition and measurement: a review
Measurement of effusion rate is a primary objective for studies that model lava flow and magma system dynamics, as well as for monitoring efforts during on-going eruptions. However, its exact definition remains a source of confusion, and problems occur when comparing volume flux values that are averaged over different time periods or spatial scales, or measured using different approaches. Thus our
Authors
Sonia Calvari, Jonathan Dehn, A. Harris
Precursory seismicity associated with frequent, large ice avalanches on Iliamna Volcano, Alaska, USA
Since 1994, at least six major (volume>106 m3) ice and rock avalanches have occurred on Iliamna volcano, Alaska, USA. Each of the avalanches was preceded by up to 2 hours of seismicity believed to represent the initial stages of failure. Each seismic sequence begins with a series of repeating earthquakes thought to represent slip on an ice-rock interface, or between layers of ice. This stage is fo
Authors
Jacqueline Caplan-Auerbach, C. Huggel