Publications
Filter Total Items: 3130
Geothermal resources in the Crater Lake area, Oregon Geothermal resources in the Crater Lake area, Oregon
No abstract available.
Authors
Charles R. Bacon, Manuel Nathenson
Type of faulting and orientation of stress and strain as a function of space and time in Kilauea's south flank, Hawaii 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...
Authors
D. Gillard, M. Wyss, P. Okubo
The 40Ar/39Ar and K/Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project The 40Ar/39Ar and K/Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project
Mauna Kea lava flows cored in the Hilo hole range in age from
Authors
W.D. Sharp, B. D. Turrin, P.R. Renne, M. A. Lanphere
Aeromagnetic map of the Clear Lake region on parts of the Santa Rosa and Ukih 1° by 2° quadrangles, California Aeromagnetic map of the Clear Lake region on parts of the Santa Rosa and Ukih 1° by 2° quadrangles, California
No abstract available.
Authors
Water Resources Division U.S. Geological Survey
The initial cooling of pahoehoe flow lobes The initial cooling of pahoehoe flow lobes
In this paper we describe a new thermal model for the initial cooling of pahoehoe lava flows. The accurate modeling of this initial cooling is important for understanding the formation of the distinctive surface textures on pahoehoe lava flows as well as being the first step in modeling such key pahoehoe emplacement processes as lava flow inflation and lava tube formation. This model is
Authors
L. Keszthelyi, R. Denlinger
Channel adjustment of an unstable coarse-grained stream: Opposing trends of boundary and critical shear stress, and the applicability of extremal hypotheses Channel adjustment of an unstable coarse-grained stream: Opposing trends of boundary and critical shear stress, and the applicability of extremal hypotheses
Channel adjustments in the North Fork Toutle River and the Toutle River main stem were initiated by deposition of a 2.5km3 debris avalanche and associated lahars that accompanied the catastrophic eruption of Mount St. Helens, Washington on 18 May 1980. Channel widening was the dominant process. In combination, adjustments caused average boundary shear stress to decrease non-linearly with...
Authors
Andrew Simon, Colin R. Thorne
Growth of the Tongariro volcanic complex: New evidence from K-Ar age determinations Growth of the Tongariro volcanic complex: New evidence from K-Ar age determinations
New K-Ar age determinations indicate that the exposed portion of the Tongariro volcanic complex has grown steadily since at least 275 ka, with intervals of vigorous cone growth at 210-200.130-70. and 25 ka to the present day.
Authors
B.J. Hobden, Bruce F. Houghton, M. A. Lanphere, I.A. Nairn
Volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory 1995 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...
Authors
Robert G. McGimsey, Christina A. Neal
Provisional geologic map of Augustine Volcano, Alaska Provisional geologic map of Augustine Volcano, Alaska
No abstract available.
Authors
R. B. Waitt, J. E. Beget, Juergen Kienle
The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics
The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036º N., long 121.883º W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip occurred on a dipping fault surface about 35...
Authors
Paul A. Spudich, Gregory C. Beroza, George Choy, John Boatwright, Stephen H. Hartzell, Gordon L. Stewart, Carlos Mendoza, Stephen Horton, John G. Anderson, Andres J. Mendez, Hiroo Kanamori, Kenji Satake, Michael Lisowski, Mark Hunter Murray, Jerry L. Svarc, Grant Marshall, Ross S. Stein, Karen McNally, Gerald W. Simila, Judy G. Brown, J.L. Nabelek, Ze’ev Reches, Mark D. Zoback, Jamison Steidl, Ralph J. Archuleta, Aaron A. Velasco, Thorne Lay, Jiajun Zhang, David J. Wald, Donald V. Helmberger, Thomas H. Heaton, Chesley R. Williams, Paul Segall, Francis T. Wu, Mingdong Wu, J.W. Rudnicki
A new model for the emplacement of Columbia River basalts as large, inflated pahoehoe lava flow fields A new model for the emplacement of Columbia River basalts as large, inflated pahoehoe lava flow fields
Extensive flows of the Columbia River Basalt (CRB) Group in Washington, Oregon, and Idaho are dominantly inflated compound pahoehoe sheet lavas. Early studies recognized that CRB lavas are compound pahoehoe flows, with textures suggesting low flow velocities, but it was thought that the great thickness and extent of the major flows required very rapid emplacement as turbulent floods of...
Authors
S. Self, Th. Thordarson, L. Keszthelyi, G.P.L. Walker, K. Hon, M.T. Murphy, P. Long, S. Finnemore
Crater Lake National Park: Presently tranquil Crater Lake National Park: Presently tranquil
No abstract available.
Authors
Hans Nelson, Charles R. Bacon