Publications
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Tracking magma volume recovery at Okmok Volcano using GPS and an unscented kalman filter
Changes beneath a volcano can be observed through position changes in a GPS network, but distinguishing the source of site motion is not always straightforward. The records of continuous GPS sites provide a favorable data set for tracking magma migration. Dense campaign observations usually provide a better spatial picture of the overall deformation field, at the expense of an episodic temporal r
Authors
T. Fournier, Jeffrey T. Freymueller, Peter Cervelli
Features of lava lake filling and draining and their implications for eruption dynamics
Lava lakes experience filling, circulation, and often drainage depending upon the style of activity and location of the vent. Features formed by these processes have proved difficult to document due to dangerous conditions during the eruption, inaccessibility, and destruction of features during lake drainage. Kilauea Iki lava lake, Kilauea, Hawai'i, preserves many such features, because lava ponde
Authors
W.K. Stovall, Bruce F. Houghton, A.J.L. Harris, D. A. Swanson
Russian eruption warning systems for aviation
More than 65 potentially active volcanoes on the Kamchatka Peninsula and the Kurile Islands pose a substantial threat to aircraft on the Northern Pacific (NOPAC), Russian Trans-East (RTE), and Pacific Organized Track System (PACOTS) air routes. The Kamchatka Volcanic Eruption Response Team (KVERT) monitors and reports on volcanic hazards to aviation for Kamchatka and the north Kuriles. KVERT scien
Authors
Christina A. Neal, Olga Girina, Sergey Senyukov, Alexander Rybin, Jeffery M. Osiensky, Pavel Izbekov, Gail Ferguson
Magma degassing triggered by static decompression at Kīlauea Volcano, Hawai‘i
During mid-June 2007, the summit of Kīlauea Volcano, Hawai‘i, deflated rapidly as magma drained from the subsurface to feed an east rift zone intrusion and eruption. Coincident with the deflation, summit SO2 emission rates rose by a factor of four before decaying to background levels over several weeks. We propose that SO2 release was triggered by static decompression caused by magma withdrawal fr
Authors
Michael P. Poland, Sutton A. Jeff, Terrence M. Gerlach
Volcanic hazards to airports
Volcanic activity has caused significant hazards to numerous airports worldwide, with local to far-ranging effects on travelers and commerce. Analysis of a new compilation of incidents of airports impacted by volcanic activity from 1944 through 2006 reveals that, at a minimum, 101 airports in 28 countries were affected on 171 occasions by eruptions at 46 volcanoes. Since 1980, five airports per ye
Authors
Marianne C. Guffanti, Gari C. Mayberry, Thomas J. Casadevall, Richard Wunderman
Age, geochemical composition, and distribution of Oligocene ignimbrites in the northern Sierra Nevada, California: Implications for landscape morphology, elevation, and drainage divide geography of the Nevadaplano
To gain a better understanding of the topographic and landscape evolution of the Cenozoic Sierra Nevada and Basin and Range, we combine geochemical and isotopic age correlations with palaeoaltimetry data from widely distributed ignimbrites in the northern Sierra Nevada, California. A sequence of Oligocene rhyolitic ignimbrites is preserved across the modern crest of the range and into the western
Authors
Elizabeth J. Cassel, Andrew T. Calvert, Stephan A. Graham
Diffuse gas emissions at the Ukinrek Maars, Alaska: Implications for magmatic degassing and volcanic monitoring
Diffuse CO2 efflux near the Ukinrek Maars, two small volcanic craters that formed in 1977 in a remote part of the Alaska Peninsula, was investigated using accumulation chamber measurements. High CO2 efflux, in many places exceeding 1000 g m−2 d−1, was found in conspicuous zones of plant damage or kill that cover 30,000–50,000 m2 in area. Total diffuse CO2 emission was estimated at 21–44 t d−1. Gas
Authors
William C. Evans, D. Bergfeld, R. G. McGimsey, A.G. Hunt
A frozen record of density-driven crustal overturn in lava lakes: The example of Kilauea Iki 1959
Lava lakes are found at basaltic volcanoes on Earth and other planetary bodies. Density-driven crustal foundering leading to surface renewal occurs repeatedly throughout the life of a lava lake. This process has been observed and described in a qualitative sense, but due to dangerous conditions, no data has been acquired to evaluate the densities of the units involved. Kilauea Iki pit crater in Ha
Authors
W.K. Stovall, Bruce F. Houghton, A.J.L. Harris, D. A. Swanson
Analytical modeling of gravity changes and crustal deformation at volcanoes: The Long Valley caldera, California, case study
Joint measurements of ground deformation and micro-gravity changes are an indispensable component for any volcano monitoring strategy. A number of analytical mathematical models are available in the literature that can be used to fit geodetic data and infer source location, depth and density. Bootstrap statistical methods allow estimations of the range of the inferred parameters. Although analytic
Authors
Maurizio Battaglia, D. P. Hill
A distal earthquake cluster concurrent with the 2006 explosive eruption of Augustine Volcano, Alaska
Clustered earthquakes located 25 km northeast of Augustine Volcano began about 6 months before and ceased soon after the volcano's 2006 explosive eruption. This distal seismicity formed a dense cluster less than 5 km across, in map view, and located in depth between 11 km and 16 km. This seismicity was contemporaneous with sharply increased shallow earthquake activity directly below the volcano's
Authors
M. A. Fisher, N.A. Ruppert, R.A. White, Frederic H. Wilson, D. Comer, R. W. Sliter, F. L. Wong
Observation and modeling of source effects in coda wave interferometry at Pavlof volcano
Sorting out source and path effects for seismic waves at volcanoes is critical for the proper interpretation of underlying volcanic processes. Source or path effects imply that seismic waves interact strongly with the volcanic subsurface, either through partial resonance in a conduit (Garces et al., 2000; Sturton and Neuberg, 2006) or by random scattering in the heterogeneous volcanic edifice (Weg
Authors
Matthew M. Haney, Wijik K. van, L.A. Preston, D.F. Aldridge
Stable isotope and petrologic evidence for open-system degassing during the climactic and pre-climactic eruptions of Mt. Mazama, Crater Lake, Oregon
Evaluation of the extent of volatile element recycling in convergent margin volcanism requires delineating likely source(s) of magmatic volatiles through stable isotopic characterization of sulfur, hydrogen and oxygen in erupted tephra with appropriate assessment of modification by degassing. The climactic eruption of Mt. Mazama ejected approximately 50 km3 of rhyodacitic magma into the atmosphere
Authors
C.W. Mandeville, J.D. Webster, C. Tappen, B.E. Taylor, A. Timbal, A. Sasaki, E. Hauri, C. R. Bacon