Publications
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Ultra-high chlorine in submarine Kı̄lauea glasses: Evidence for direct assimilation of brine by magma
Basaltic glass grains from the submarine south flank of Kı̄lauea, Hawai′i, have Cl concentrations of 0.01–1.68 wt%, the latter being the highest Cl content yet recorded for a Hawaiian glass. The high-Cl glass grains are products of brine assimilation by tholeiite magma. The glasses are grains in a sandstone clast from bedded breccias draping the southwestern margin of Kı̄lauea’s submarine midslope
Authors
Michelle L. Coombs, Thomas W. Sisson, Jun-Ichi Kimura
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, 10.1029/2001GC00
Authors
M. Mangan, L. Mastin, T. Sisson
Mapping recent lava flows at Westdahl Volcano, Alaska, using radar and optical satellite imagery
Field mapping of young lava flows at Aleutian volcanoes is logistically difficult, and the utility of optical images from aircraft or satellites for this purpose is greatly reduced by persistent cloud cover. These factors have hampered earlier estimates of the areas and volumes of three young lava flows at Westdahl Volcano, including its most recent (1991–1992) flow. We combined information from s
Authors
Z. Lu, Russ Rykhus, Timothy Masterlark, K.G. Dean
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 ± 7000 yr. Is
Authors
M. A. Lanphere, D. E. Champion, M.A. Clynne, J. B. Lowenstern, A.M. Sarna-Wojcicki, J. L. Wooden
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 inversion, and
Authors
S. Bannister, C.J. Bryan, H.M. Bibby
Geochemical constraints on possible subduction components in lavas of Mayon and Taal Volcanoes, Southern Luzon, Philippines
Mayon is the most active volcano along the east margin of southern Luzon, Philippines. Petrographic and major element data indicate that Mayon has produced a basaltic to andesitic lava series by fractional crystallization and magma mixing. Trace element data indicate that the parental basalts came from a heterogeneous mantle source. The unmodified composition of the mantle wedge is similar to that
Authors
P.R. Castillo, C. G. Newhall
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 in the proc
Authors
W. Marzocchi, L. Sandri, P. Gasparini, C. Newhall, Enzo Boschi
Application of near real-time radial semblance to locate the shallow magmatic conduit at Kilauea Volcano, Hawaii
Radial Semblance is applied to broadband seismic network data to provide source locations of Very-Long-Period (VLP) seismic energy in near real time. With an efficient algorithm and adequate network coverage, accurate source locations of VLP energy are derived to quickly locate the shallow magmatic conduit system at Kilauea Volcano, Hawaii. During a restart in magma flow following a brief pause in
Authors
P. Dawson, D. Whilldin, B. Chouet
Earthquake triggering at Alaskan volcanoes following the 3 November 2002 Denali fault earthquake
The 3 November 2002 Mw 7.9 Denali fault earthquake provided an excellent opportunity to investigate triggered earthquakes at Alaskan volcanoes. The Alaska Volcano Observatory operates short-period seismic networks on 24 historically active volcanoes in Alaska, 247-2159 km distant from the mainshock epicenter. We searched for evidence of triggered seismicity by examining the unfiltered waveforms fo
Authors
S.C. Moran, J.A. Power, S.D. Stihler, J.J. Sanchez, J. Caplan-Auerbach
Migration and rearing histories of chinook salmon (Oncorhynchus tshawytscha) determined by ion microprobe Sr isotope and Sr/Ca transects of otoliths
Strontium isotope and Sr/Ca ratios measured in situ by ion microprobe along radial transects of otoliths of juvenile chinook salmon (Oncorhynchus tshawytscha) vary between watersheds with contrasting geology. Otoliths from ocean-type chinook from Skagit River estuary, Washington, had prehatch regions with 87Sr/86Sr ratios of ~0.709, suggesting a maternally inherited marine signature, extensive fre
Authors
C. R. Bacon, P.K. Weber, K.A. Larsen, R. Reisenbichler, J.A. Fitzpatrick, J. L. Wooden
Triggered deformation and seismic activity under Mammoth Mountain in Long Valley caldera by the 3 November 2002 Mw 7.9 Denali fault earthquake
The 3 November 2002 Mw 7.9 Denali fault earthquake triggered deformational offsets and microseismicity under Mammoth Mountain (MM) on the rim of Long Valley caldera, California, some 3460 km from the earthquake. Such strain offsets and microseismicity were not recorded at other borehole strain sites along the San Andreas fault system in California. The Long Valley offsets were recorded on borehole
Authors
M.J.S. Johnston, S. G. Prejean, D. P. Hill
Debris flows: geologic process and hazard; illustrated by a surge sequence at Jiangjia Ravine, Yunnan, China
Debris flows are slurries of sediment and water that are both an important geologic process and a major hazard. They present large risks to those living in mountainous areas, as well as downstream from volcanoes in the case of the flows known as lahars that may travel 100200 kilometers (62-124 miles). The accompanying video records a series of debris flow surges at Jiangjia Ravine, in Yunnan Prov
Authors
Kevin M. Scott, Wang Yuyi