Publications
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Mount St. Augustine volcano fumarole wall rock alteration: Mineralogy, zoning, composition and numerical models of its formation process
Intensely altered wall rock was collected from high-temperature (640 °C) and low-temperature (375 °C) vents at Augustine volcano in July 1989. The high-temperature altered rock exhibits distinct mineral zoning differentiated by color bands. In order of decreasing temperature, the color bands and their mineral assemblages are: (a) white to grey (tridymite-anhydrite); (b) pink to red (tridymite-hema
Authors
A. Getahun, M.H. Reed, R. Symonds
Origin and depositional environment of clastic deposits in the Hilo drill hole, Hawaii
Volcaniclastic units cored at depths of about 87, 164, 178, 226, and 246 m below sea level and carbonate units located between depths of 27 and 53 m below sea level in the Hilo drill core were found to be deposited at or near sea level. Four of these units are hydroclastic deposits, formed when subaerially erupted Mauna Loa lava flows entered the ocean and fragmented to produce quenched, glassy fr
Authors
M.H. Beeson, D. A. Clague, J. P. Lockwood
Mauna Loa lava accumulation rates at the Hilo drill site: Formation of lava deltas during a period of declining overall volcanic growth
Accumulation rates for lava flows erupted from Mauna Loa, as sampled in the uppermost 280 m of the Hilo drill hole, vary widely for short time intervals (several thousand years), but overall are broadly similar to those documented elsewhere on this volcano since 100 ka. Thickness variations and accumulation rates for Mauna Loa lavas at the Hilo drill site have been strongly affected by local paleo
Authors
P. W. Lipman, J. G. Moore
Rockslide-debris avalanche of May 18, 1980, Mount St. Helens Volcano, Washington
This report provides a detailed picture of the rockslide-debris avalanche of the May 18, 1980, eruption of Mount St. Helens volcano. It provides a characterization of the deposit, a reinterpretation of the details of the first minutes of the eruption of May 18, and insight into the transport mechanism of the mass movement.
Details of the rockslide event, as revealed by eyewitness photographs, are
Authors
Harry Glicken
Catalog of earthquake hypocenters for Augustine, Redoubt, Iliamna, and Mount Spurr volcanoes, Alaska: January 1, 1991 - December 31, 1993
The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska, Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained a program of seismic monitoring at potentially active volcanoes in the Cook Inlet region since 1988. The principal objectives of this program include the seismic sur
Authors
Arthur D. Jolly, John A. Power, Scott D. Stihler, Lalitha N. Rao, Gail Davidson, John F. Paskievitch, Steve Estes, John C. Lahr
Volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory 1995
The Alaska Volcano Observatory (AVO) responded to eruptive activity or suspected volcanic activity (SVA) at 6 volcanic centers in 1995: Mount Martin (Katmai Group), Mount Veniaminof, Shishaldin, Makushin, Kliuchef/Korovin, and Kanaga. In addition to responding to eruptive activity at Alaska volcanoes, AVO also disseminated information for the Kamchatkan Volcanic Eruption Response Team (KVERT) on t
Authors
Robert G. McGimsey, Christina A. Neal
Aeromagnetic survey over U.S. to advance geomagnetic research
A proposed high‐altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic‐anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER‐2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The collection of tota
Authors
T. G. Hildenbrand, R. J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
Type of faulting and orientation of stress and strain as a function of space and time in Kilauea's south flank, Hawaii
Earthquake focal mechanisms of events occurring between 1972 and 1992 in the south flank of Kilauea volcano, Hawaii, are used to infer the state of stress and strain as a function of time and space. We have determined 870 fault plane solutions from P wave first motion polarities for events with magnitudes ML ≥ 2.5 and depth ranging between 6 and 12 km. Faulting is characterized by a mixture of dec
Authors
D. Gillard, M. Wyss, P. Okubo
Hot dry rock and the U.S. geological survey: a question of priorities
The enactment of the Energy Policy Act of 1992 saw the assignment of definite responsibilities relating to hot dry rock (HDR) to the US Geological Survey (USGS). This mandate provided some explicit guidelines and individual tasks in areas in which the USGS already had close ties to the Department of Energy and a number of its national laboratories. This paper discusses various tasks in terms of pr
Authors
John H. Sass
Recurrent eruption and subsidence at the Platoro caldera complex, southeastern San Juan volcanic field, Colorado: New tales from old tuffs
Reinterpretation of a voluminous regional ash-flow sheet (Masonic Park Tuff) as two separate tuff sheets of similar phenocryst-rich dacite erupted from separate source calderas has important implications for evolution of the multicyclic Platoro caldera complex and for caldera-forming processes generally. Masonic Park Tuff in central parts of the San Juan field, including the type area, was erupted
Authors
P. W. Lipman, M.A. Dungan, L.L. Brown, A. Deino
Outburst floods from glacier-dammed lakes: The effect of mode of lake drainage on flood magnitude
Published accounts of outburst floods from glacier‐dammed lakes show that a significant number of such floods are associated not with drainage through a tunnel incised into the basal ice—the process generally assumed—but rather with ice‐marginal drainage, mechanical failure of part of the ice dam, or both. Non‐tunnel floods are strongly correlated with formation of an ice dam by a glacier advancin
Authors
Joseph S. Walder, John E. Costa
Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania
As a comparison to airborne infrared (IR) flux measurements, ground-based sampling of fumarole and soil gases was used to characterize the quiescent degassing of CO2 from Oldoinyo Lengai volcano. Aerial and ground-based measurements are in good agreement: ~75% of the aerially measured CO2 flux at Lengai (0.05-0.06 x 1012 mol yr-1 or 6000-7200 tonnes CO2 d-1) can be attributed to seven large crater
Authors
K.W. Koepenick, S.L. Brantley, J. M. Thompson, G.L. Rowe, A.A. Nyblade, C. Moshy