Publications
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Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan
This study investigates 31 years of fumarole gas and condensate (trace elements) data from Showa-Shinzan, a dacitic dome-cryptodome complex that formed during the 1943-1945 eruption of Usu volcano. Forty-two gas samples were collected from the highest-temperature fumarole, named A-1, from 1954 (800??C) to 1985 (336??C), and from lower-temperature vents. Condensates were collected...
Authors
R.B. Symonds, Y. Mizutani, Paul H. Briggs
Exsolved magmatic fluid and its role in the formation of comb-layered quartz at the Cretaceous Logtung W-Mo deposit, Yukon Territory, Canada Exsolved magmatic fluid and its role in the formation of comb-layered quartz at the Cretaceous Logtung W-Mo deposit, Yukon Territory, Canada
Comb-layered quartz is a type of unidirectional solidification texture found at the roofs of shallow silicic intrusions that are often associated spatially with Mo and W mineralisation. The texture consists of multiple layers of euhedral, prismatic quartz crystals (Type I) that have grown on subplanar aplite substrates. The layers are separated by porphyritic aplite containing equant...
Authors
J. B. Lowenstern, W.D. Sinclair
This dynamic earth: the story of plate tectonics This dynamic earth: the story of plate tectonics
In the early 1960s, the emergence of the theory of plate tectonics started a revolution in the earth sciences. Since then, scientists have verified and refined this theory, and now have a much better understanding of how our planet has been shaped by plate-tectonic processes. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and...
Authors
W. Jacquelyne Kious, Robert I. Tilling
Sedimentary processes in a tectonically active region: Puerto Rico north insular slope Sedimentary processes in a tectonically active region: Puerto Rico north insular slope
No abstract available.
Authors
Kathryn M. Scanlon, Douglas G. Masson
City of Flagstaff Project: Ground Water Resource Evaluation, Remote Sensing Component City of Flagstaff Project: Ground Water Resource Evaluation, Remote Sensing Component
Many regions, cities, and towns in the Western United States need new or expanded water resources because of both population growth and increased development. Any tools or data that can help in the evaluation of an area's potential water resources must be considered for this increasingly critical need. Remotely sensed satellite images and subsequent digital image processing have been...
Authors
Pat S. Chavez, Miguel G. Velasco, Jo-Ann Bowell, Stuart C. Sides, Rosendo R. Gonzalez, Deborah L. Soltesz
Damage and restoration of geodetic infrastructure caused by the 1994 Northridge, California, earthquake Damage and restoration of geodetic infrastructure caused by the 1994 Northridge, California, earthquake
We seek to restore the integrity of the geodetic network in the San Fernando, Simi, Santa Clarita Valleys and in the northern Los Angeles Basin by remeasurement of the network and identification of BMs which experienced non-tectonic displacements associated with the Northridge earthquake. We then use the observed displacement of BMs in the network to portray or predict the permanent...
Authors
Kathleen M. Hodgkinson, Ross S. Stein, Kenneth W. Hudnut, Jay Satalich, John H. Richards
Earthquake technology fights crime Earthquake technology fights crime
Scientists with the U.S. Geological Survey have adapted their methods for quickly finding the exact source of an earthquake to the problem of locating gunshots. On the basis of this work, a private company is now testing an automated gunshot-locating system in a San Francisco Bay area community. This system allows police to rapidly pinpoint and respond to illegal gunfire, helping to...
Authors
John C. Lahr, Peter L. Ward, Peter H. Stauffer, James W. Hendley
Catalog of earthquake hypocenters for Augustine, Redoubt, Iliamna, and Mount Spurr volcanoes, Alaska: January 1, 1991 - December 31, 1993 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...
Authors
Arthur D. Jolly, John A. Power, Scott D. Stihler, Lalitha N. Rao, Gail Davidson, John F. Paskievitch, Steve Estes, John C. Lahr
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
Chemical analyses for the geologic map of the Island of Hawaii Chemical analyses for the geologic map of the Island of Hawaii
No abstract available.
Authors
E.W. Wolfe
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
Database of potential sources for earthquakes larger than magnitude 6 in Northern California Database of potential sources for earthquakes larger than magnitude 6 in Northern California
The Northern California Earthquake Potential (NCEP) working group, composed of many contributors and reviewers in industry, academia and government, has pooled its collective expertise and knowledge of regional tectonics to identify potential sources of large earthquakes in northern California. We have created a map and database of active faults, both surficial and buried, that forms the...
Authors