Publications
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Abrupt transitions during sustained explosive eruptions: Examples from the 1912 eruption of Novarupta, Alaska
Plinian/ignimbrite activity stopped briefly and abruptly 16 and 45 h after commencement of the 1912 Novarupta eruption defining three episodes of explosive volcanism before finally giving way after 60 h to effusion of lava domes. We focus here on the processes leading to the termination of the second and third of these three episodes. Early erupted pumice from both episodes show a very...
Authors
N.K. Adams, Bruce F. Houghton, W. Hildreth
Are migrating raptors guided by a geomagnetic compass?
We tested whether routes of raptors migrating over areas with homogeneous topography follow constant geomagnetic courses more or less closely than constant geographical courses. We analysed the routes taken over land of 45 individual raptors tracked by satellite-based radiotelemetry: 25 peregrine falcons, Falco peregrinus, on autumn migration between North and South America, and seven...
Authors
Kasper Thorup, Mark R. Fuller, T. Alerstam, M. Hake, N. Kjellen, R. Standberg
Interferometric synthetic aperture radar: Building tomorrow's tools today
A synthetic aperture radar (SAR) system transmits electromagnetic (EM) waves at a wavelength that can range from a few millimeters to tens of centimeters. The radar wave propagates through the atmosphere and interacts with the Earth’s surface. Part of the energy is reflected back to the SAR system and recorded. Using a sophisticated image processing technique, called SAR processing...
Authors
Zhong Lu
Acoustic stratigraphy of Bear Lake, Utah-Idaho: late Quaternary sedimentation patterns in a simple half-graben
A 277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake's paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on the age model for the drill core, the...
Authors
Steven M. Colman
Probabilistic analysis of tsunami hazards
Determining the likelihood of a disaster is a key component of any comprehensive hazard assessment. This is particularly true for tsunamis, even though most tsunami hazard assessments have in the past relied on scenario or deterministic type models. We discuss probabilistic tsunami hazard analysis (PTHA) from the standpoint of integrating computational methods with empirical analysis of...
Authors
E.L. Geist, T. Parsons
Puhimau thermal area: a window into the upper east rift zone of Kilauea Volcano, Hawaii?
We report the results of two soil CO2 efflux surveys by the closed chamber circulation method at the Puhimau thermal area in the upper East Rift Zone (ERZ) of Kilauea volcano, Hawaii. The surveys were undertaken in 1996 and 1998 to constrain how much CO2 might be reaching the ERZ after degassing beneath the summit caldera and whether the Puhimau thermal area might be a significant...
Authors
K.A. McGee, A. J. Sutton, T. Elias, M.P. Doukas, T.M. Gerlach
Evidence of phyllosilicates in Wooly Patch, an altered rock encountered at West Spur, Columbia Hills, by the Spirit rover in Gusev crater, Mars
On its traverse to Columbia Hills, the Mars Exploration Rover Spirit investigated an outcrop designated “Wooly Patch” that exhibited morphological, mineralogical, and geochemical characteristics at the extreme ends of ranges observed among rocks studied at West Spur, a westward projecting salient near the foot of the Columbia Hills, Gusev crater. The major‐element composition and Fe...
Authors
A. Wang, R.L. Korotev, B.L. Jolliff, L.A. Haskin, L. Crumpler, W. H. Farrand, Kenneth E. Herkenhoff, Jr. de Souza, A.G. Kusack, J.A. Hurowitz, N.J. Tosca
North Kona slump: Submarine flank failure during the early(?) tholeiitic shield stage of Hualalai Volcano
The North Kona slump is an elliptical region, about 20 by 60 km (1000-km2 area), of multiple, geometrically intricate benches and scarps, mostly at water depths of 2000–4500 m, on the west flank of Hualalai Volcano. Two dives up steep scarps in the slump area were made in September 2001, using the ROV Kaiko of the Japan Marine Science and Technology Center (JAMSTEC), as part of a...
Authors
P. W. Lipman, M.L. Coombs
Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa
Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of...
Authors
Peter W. Lipman, Thomas W. Sisson, Michelle L. Coombs, Andrew T. Calvert, Jun-Ichi Kimura
Flood lavas on Earth, Io and Mars
Flood lavas are major geological features on all the major rocky planetary bodies. They provide important insight into the dynamics and chemistry of the interior of these bodies. On the Earth, they appear to be associated with major and mass extinction events. It is therefore not surprising that there has been significant research on flood lavas in recent years. Initial models suggested...
Authors
Laszlo P. Keszthelyi, Stephen Self, Thorvaldur Thordarson
Spirit rover localization and topographic mapping at the landing site of Gusev crater, Mars
By sol 440, the Spirit rover has traversed a distance of 3.76 km (actual distance traveled instead of odometry). Localization of the lander and the rover along the traverse has been successfully performed at the Gusev crater landing site. We localized the lander in the Gusev crater using two-way Doppler radio positioning and cartographic triangulations through landmarks visible in both...
Authors
Rongxing Li, Brent A. Archinal, Raymond E. Arvidson, Jim Bell, Phillip R. Christensen, Larry S. Crumpler, David J. Des Marais, Kaichang Di, Tom Duxbury, Matthew P. Golombek, John Grant, Ronald Greeley, Joe Guinn, Aaron H. Johnson, Randolph L. Kirk, Mark Maimone, Larry H. Matthies, Michael Malin, Timothy Parker, Michael H. Sims, Shane D. Thompson, Steven W. Squyres, Laurence A. Soderblom
Argon geochronology of Kilauea's early submarine history
Submarine alkalic and transitional basalts collected by submersible along Kilauea volcano's south flank represent early eruptive products from Earth's most active volcano. Strongly alkalic basalt fragments sampled from volcaniclastic deposits below the mid-slope Hilina Bench yield 40Ar/39Ar ages from 212 ± 38 to 280 ± 20 ka. These ages are similar to high-precision 234 ± 9 and 239 ± 10...
Authors
Andrew T. Calvert, Marvin A. Lanphere