Publications
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Prediction in geomorphology Prediction in geomorphology
No abstract available.
Authors
Peter R. Wilcock, Richard M. Iverson
Gravity-driven mass flows Gravity-driven mass flows
Gravity-driven mass flows, also known as sediment gravity flows, include a spectrum of phenomena in which more-or-less coherent mixtures of grains and intergranular fluid flow down slopes. At one end of this spectrum are dilute flows in which momentum is transferred mostly by fluid forces and sediment is largely a passive cargo that increases the effective fluid density. These dilute...
Authors
Richard M. Iverson
How should mathematical models of geomorphic processes be judged? How should mathematical models of geomorphic processes be judged?
No abstract available.
Authors
Richard M. Iverson
Preliminary volcano-hazard assessment for Great Sitkin Volcano, Alaska Preliminary volcano-hazard assessment for Great Sitkin Volcano, Alaska
Great Sitkin Volcano is a composite andesitic stratovolcano on Great Sitkin Island (51°05’ N latitude, 176°25’ W longitude), a small (14 x 16 km), circular volcanic island in the western Aleutian Islands of Alaska. Great Sitkin Island is located about 35 kilometers northeast of the community of Adak on Adak Island and 130 kilometers west of the community of Atka on Atka Island. Great...
Authors
Christopher F. Waythomas, Thomas P. Miller, Christopher J. Nye
Infrasonic tremor observed at Kilauea Volcano, Hawai'i Infrasonic tremor observed at Kilauea Volcano, Hawai'i
[1] Infrasonic array data collected at Kīlauea Volcano, Hawai'i, during November 12–21, 2002 indicate that the active vents and lava tube system near the Pu'u 'Ō'ō vent complex emit almost continuous infrasound in the 0.3–10 Hz frequency band. The spectral content of these infrasonic signals matches well that of synchronous seismic tremor. In sites protected from wind noise, significant...
Authors
M. Garces, A. Harris, C. Hetzer, J. Johnson, S. Rowland, E. Marchetti, P. Okubo
Volcano seismology Volcano seismology
A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of portable broadband seismic instrumentation, availability...
Authors
B. Chouet
New K-Ar ages and the geologic evidence against rejuvenated-stage volcanism at Haleakalā, East Maui, a postshield-stage volcano of the Hawaiian island chain New K-Ar ages and the geologic evidence against rejuvenated-stage volcanism at Haleakalā, East Maui, a postshield-stage volcano of the Hawaiian island chain
The postshield and previously inferred rejuvenated-stage history of Haleakalā volcano is reevaluated on the basis of 52 new K-Ar ages, 42 from the postshield Kula Volcanics and 10 from the overlying Hāna Volcanics. Postshield extrusion was robust from 0.93 to 0.76 Ma. A period of low extrusion rate or volcanic quiescence occurred between 0.76 and 0.65 Ma, well within Kula time. A...
Authors
David R. Sherrod, Yoshitomo Nishimitsu, Takahiro Tagami
Preliminary geologic map of Great Sitkin Volcano, Alaska Preliminary geologic map of Great Sitkin Volcano, Alaska
No abstract available.
Authors
Christopher F. Waythomas, Thomas P. Miller, Christopher Nye
Preliminary geologic map of Kanaga Volcano, Alaska Preliminary geologic map of Kanaga Volcano, Alaska
Kanaga Volcano is a 1,300 m (4,287-foot) high, historically active cone-shaped stratovolcano located on the north end of Kanaga Island in the Andreanof Islands Group of the Aleutian Islands. The volcano is undissected, symmetrical in profile, and is characterized by blocky andesitic lava flows, with well-developed levees and steep flow fronts, that emanate radially from, or near, the 200...
Authors
T. P. Miller, C. F. Waythomas, C.J. Nye
Monthly Strontium/Calcium oscillations in symbiotic coral aragonite: Biological effects limiting the precision of the paleotemperature proxy Monthly Strontium/Calcium oscillations in symbiotic coral aragonite: Biological effects limiting the precision of the paleotemperature proxy
In thermodynamic equilibrium with sea water the Sr/Ca ratio of aragonite varies predictably with temperature and the Sr/Ca ratio in coral have thus become a frequently used proxy for past Sea Surface Temperature (SST). However, biological effects can offset the Sr/Ca ratio from its equilibrium value. We report high spatial resolution ion microprobe analyses of well defined skeletal...
Authors
A. Meibom, M. Stage, Joseph L. Wooden, B.R. Constantz, R. B. Dunbar, A. Owen, N. Grumet, C. R. Bacon, C. P. Chamberlain
Debris-flow hazards caused by hydrologic events at Mount Rainier, Washington Debris-flow hazards caused by hydrologic events at Mount Rainier, Washington
At 4393 m, ice-clad Mount Rainier has great potential for debris flows owing to its precipitous slopes and incised steep valleys, the large volume of water stored in its glaciers, and a mantle of loose debris on its slopes. In the past 10,000 years, more than sixty Holocene lahars have occurred at Mount Rainier (Scott et al., 1985), and, in addition more than thirty debris flows not...
Authors
James W. Vallance, Michelle L. Cunico, Steve P. Schilling
A compilation of whole-rock and glass major-element geochemistry of Kilauea Volcano, Hawai'i, near-vent eruptive products: January 1983 through September 2001 A compilation of whole-rock and glass major-element geochemistry of Kilauea Volcano, Hawai'i, near-vent eruptive products: January 1983 through September 2001
This report presents major-element geochemical data from 652 glasses (~6,520 analyses) and 795 whole-rock aliquots from 1,002 fresh samples of olivine-tholeiitic lava collected throughout the near-continuous eruption of Kïlauea Volcano, Hawai'i, from January 1983 through September 2001. The data presented herein provide a unique temporal compilation of lava geochemistry that best...
Authors
Carl R. Thornber, Ken Hon, Christina Heliker, David A. Sherrod