Publications
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Gas evolution in eruptive conduits: Combining insights from high temperature and pressure decompression experiments with steady-state flow modeling Gas evolution in eruptive conduits: Combining insights from high temperature and pressure decompression experiments with steady-state flow modeling
In this paper we examine the consequences of bubble nucleation mechanism on eruptive degassing of rhyolite magma. We use the results of published high temperature and pressure decompression experiments as input to a modified version of CONFLOW, the numerical model of Mastin and Ghiorso [(2000) U.S.G.S. Open-File Rep. 00-209, 53 pp.] and Mastin [(2002) Geochem. Geophys. Geosyst. 3, 10...
Authors
M. Mangan, L. Mastin, T. Sisson
Age of the Rockland tephra, western USA Age of the Rockland tephra, western USA
The age of the Rockland tephra, which includes an ash-flow tuff south and west of Lassen Peak in northern California and a widespread ash-fall deposit that produced a distinct stratigraphic marker in western North America, is constrained to 565,000 to 610,000 yr by 40Ar/39Ar and U–Pb dating. 40Ar/39Ar ages on plagioclase from pumice in the Rockland have a weighted mean age of 609,000 ±...
Authors
M. A. Lanphere, D.E. Champion, M.A. Clynne, J. B. Lowenstern, A.M. Sarna-Wojcicki, J. L. Wooden
Role of a large marine protected area for conserving landscape attributes of sand habitats on Georges Bank (NW Atlantic) Role of a large marine protected area for conserving landscape attributes of sand habitats on Georges Bank (NW Atlantic)
Mobile fishing gear reduces seafloor habitat complexity through the removal of structure-building fauna, e.g. emergent organisms that create pits and burrows, as well as by smoothing of sedimentary bedforms (e.g. sand ripples). In this study, we compared the relative abundance of microhabitat features (the scale at which individual fish associate with seafloor habitat) inside and outside...
Authors
J. Lindholm, P. Auster, P. Valentine
Precise relocation of earthquakes following the 15 June 1991 eruption of Mount Pinatubo (Philippines) Precise relocation of earthquakes following the 15 June 1991 eruption of Mount Pinatubo (Philippines)
The 15 June 1991 climactic eruption of Mount Pinatubo (Philippines) was followed by intense seismicity that remained at a high level for several months. We located 10,839 events recorded between 1 July and mid-December 1991. In contrast to the preeruptive seismicity which was focused in two groups below the summit area, posteruptive events were widely distributed below and around the...
Authors
J. Battaglia, C.H. Thurber, J.-L. Got, C.A. Rowe, R.A. White
High-rate real-time GPS network at Parkfield: Utility for detecting fault slip and seismic displacements High-rate real-time GPS network at Parkfield: Utility for detecting fault slip and seismic displacements
A network of 13 continuous GPS stations near Parkfield, California has been converted from 30 second to 1 second sampling with positions of the stations estimated in real-time relative to a master station. Most stations are near the trace of the San Andreas fault, which exhibits creep. The noise spectra of the instantaneous 1 Hz positions show flicker noise at high frequencies and change...
Authors
J. Langbein, Y. Bock
Wind-related processes detected by the Spirit rover at Gusev crater, Mars Wind-related processes detected by the Spirit rover at Gusev crater, Mars
Wind-abraded rocks, ripples, drifts, and other deposits of windblown sediments are seen at the Columbia Memorial Station where the Spirit rover landed. Orientations of these features suggest formative winds from the north-northwest, consistent with predictions from atmospheric models of afternoon winds in Gusev Crater. Cuttings from the rover Rock Abrasion Tool are asymmetrically...
Authors
R. Greeley, S. W. Squyres, R. E. Arvidson, P. Bartlett, J.F. Bell, D. Blaney, N.A. Cabrol, J. Farmer, B. Farrand, M.P. Golombek, S.P. Gorevan, J. A. Grant, A. F. C. Haldemann, Kenneth E. Herkenhoff, J. Johnson, G. Landis, M.B. Madsen, S.H. McLennan, J. Moersch, J. W. Rice, L. Richter, S. Ruff, R.J. Sullivan, S.D. Thompson, A. Wang, C.M. Weitz, P. Whelley
Localization and physical properties experiments conducted by Spirit at Gusev crater Localization and physical properties experiments conducted by Spirit at Gusev crater
The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne...
Authors
R. E. Arvidson, R. C. Anderson, P. Bartlett, J.F. Bell, D. Blaney, P. R. Christensen, P. Chu, L. Crumpler, K. Davis, B.L. Ehlmann, R. Fergason, M.P. Golombek, S. Gorevan, J. A. Grant, R. Greeley, E.A. Guinness, A. F. C. Haldemann, Kenneth E. Herkenhoff, J. Johnson, G. Landis, R. Li, R. Lindemann, H. McSween, D. W. Ming, T. Myrick, L. Richter, F.P. Seelos, S. W. Squyres, R.J. Sullivan, A. Wang, Jim Wilson
Pancam multispectral imaging results from the Spirit Rover at Gusev crater Pancam multispectral imaging results from the Spirit Rover at Gusev crater
Panoramic Camera images at Gusev crater reveal a rock-strewn surface interspersed with high- to moderate-albedo fine-grained deposits occurring in part as drifts or in small circular swales or hollows. Optically thick coatings of fine-grained ferric iron-rich dust dominate most bright soil and rock surfaces. Spectra of some darker rock surfaces and rock regions exposed by brushing or...
Authors
J.F. Bell, S. W. Squyres, R. E. Arvidson, H.M. Arneson, D. Bass, D. Blaney, N. Cabrol, W. Calvin, J. Farmer, W. H. Farrand, W. Goetz, M. Golombek, J. A. Grant, R. Greeley, E. Guinness, A. G. Hayes, M.Y.H. Hubbard, Kenneth E. Herkenhoff, M. J. Johnson, J. R. Johnson, J. Joseph, K.M. Kinch, M.T. Lemmon, R. Li, M.B. Madsen, J.N. Maki, M. Malin, E. McCartney, S. McLennan, H.Y. McSween, D. W. Ming, J.E. Moersch, R.V. Morris, E.Z.N. Dobrea, T. J. Parker, J. Proton, J. W. Rice, F. Seelos, J. Soderblom, Laurence A. Soderblom, J. N. Sohl-Dickstein, R.J. Sullivan, M.J. Wolff, A. Wang
Volcanological perspectives on Long Valley, Mammoth Mountain, and Mono Craters: Several contiguous but discrete systems Volcanological perspectives on Long Valley, Mammoth Mountain, and Mono Craters: Several contiguous but discrete systems
The volcanic history of the Long Valley region is examined within a framework of six successive (spatially discrete) foci of silicic magmatism, each driven by locally concentrated basaltic intrusion of the deep crust in response to extensional unloading and decompression melting of the upper mantle. A precaldera dacite field (3.5–2.5 Ma) northwest of the later site of Long Valley and the...
Authors
W. Hildreth
Surficial deposits at Gusev crater along Spirit Rover traverses Surficial deposits at Gusev crater along Spirit Rover traverses
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes. Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth. Some rocks have been textured and/or partially buried by windblown...
Authors
J. A. Grant, R. Arvidson, J.F. Bell, N.A. Cabrol, M. H. Carr, P. Christensen, L. Crumpler, D.J. Des Marais, B.L. Ehlmann, J. Farmer, M. Golombek, F.D. Grant, R. Greeley, Kenneth E. Herkenhoff, R. Li, H.Y. McSween, D. W. Ming, J. Moersch, J. W. Rice, S. Ruff, L. Richter, S. Squyres, R. Sullivan, C. Weitz
Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion
The Taupo Volcanic Zone (TVZ), New Zealand is a region characterized by very high magma eruption rates and extremely high heat flow, which is manifest in high-temperature geothermal waters. The shear wave velocity structure across the region is inferred using non-linear inversion of receiver functions, which were derived from teleseismic earthquake data. Results from the non-linear...
Authors
S. Bannister, C.J. Bryan, H.M. Bibby
Quantifying probabilities of volcanic events: The example of volcanic hazard at Mount Vesuvius Quantifying probabilities of volcanic events: The example of volcanic hazard at Mount Vesuvius
We describe an event tree scheme to quantitatively estimate both long- and short-term volcanic hazard. The procedure is based on a Bayesian approach that produces a probability estimation of any possible event in which we are interested and can make use of all available information including theoretical models, historical and geological data, and monitoring observations. The main steps...
Authors
W. Marzocchi, L. Sandri, P. Gasparini, C. Newhall, Enzo Boschi