Publications
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Effects of volcanism on the glaciers of Mount St. Helens Effects of volcanism on the glaciers of Mount St. Helens
The cataclysmic eruption of Mount St. Helens May 18, 1980, removed 2.9 km2 (about 0.13 km3) of glacier snow and ice including a large part of Shoestring, Forsyth, Wishbone, Ape, Nelson, and all of Loowit and Leschi Glaciers. Minor eruptions and bulging of the volcano from March 27 to May 17 shattered glaciers which were on the deforming rock and deposited ash on other glaciers. Thick ash...
Authors
Melinda M. Brugman, Austin Post
Potassium-argon ages from the Mount Taylor Volcanic Field, New Mexico Potassium-argon ages from the Mount Taylor Volcanic Field, New Mexico
Fourteen new K-Ar dates for volcanic rocks of the Mount Taylor field, New Mexico, indicate that most activity occurred between 4.3 and 1.5 m.y. (million years) ago. Peak activity was at about 3.0-2.5 m.y., both on the central andesite-rhyolite shield volcano and on the surrounding alkali basalt-trachyte volcanic plateau, and occurred concurrently with an episode of NNE-trending basin...
Authors
Peter W. Lipman, Harald H. Mehnert
Late Cenozoic volcanism, geochronology, and structure of the Coso Range, Inyo County, California Late Cenozoic volcanism, geochronology, and structure of the Coso Range, Inyo County, California
The Coso Range lies at the west edge of the Great Basin, adjacent to the southern part of the Sierra Nevada. A basement complex of pre‐Cenozoic plutonic and metamorphic rocks is partly buried by ∼35 km3 of late Cenozoic volcanic rocks that were erupted during two periods, as defined by K‐Ar dating: (1) 4.0–2.5 m.y., ∼31 km3 of basalt, rhyodacite, dacite, andesite, and rhyolite, in...
Authors
Wendell A. Duffield, Charles R. Bacon, G. Brent Dalrymple
Comment and reply on ‘Comparison of Miocene provincial foraminiferal stages to coccolith zones in the California Continental Borderland’: Reply Comment and reply on ‘Comparison of Miocene provincial foraminiferal stages to coccolith zones in the California Continental Borderland’: Reply
No abstract avalable.
Authors
James K. Crouch, David Bukry
Distribution of Quaternary rhyolite domes of the Coso Range, California: implications for extent of the geothermal anomaly. Distribution of Quaternary rhyolite domes of the Coso Range, California: implications for extent of the geothermal anomaly.
38 separate domes and flows of phenocryst-poor, high-silica rhyolite of similar major element chemical composition were erupted over the past 1My from vents arranged in a crudely S-shaped array atop a granitic horst in the Coso Range, California. Most of the extrusions are probably less than about 0.3My old. The central part of the rhyolite field is characterized by high heat flow, low...
Authors
C. R. Bacon, W. A. Duffield
Bulk density and magnetization measurements of samples from the Coso Range, California Bulk density and magnetization measurements of samples from the Coso Range, California
No abstract available.
Authors
Donald Plouff, William F. Isherwood, Charles R. Bacon, Wendell A. Duffield, H. Mark Van Buren
Geological and geophysical investigations and mineral resources potential of the proposed Great Rift Wilderness Area, Idaho Geological and geophysical investigations and mineral resources potential of the proposed Great Rift Wilderness Area, Idaho
No abstract available.
Authors
Mel A. Kuntz, Richard H. Lefebvre, Duane E. Champion, Lisa A. McBroome, Don R. Mabey, W. D. Stanley, H. R. Covington, James Ridenour, Ronald B. Stotelmeyer
Potential hazards from future eruptions in the vicinity of Mount Shasta Volcano, Northern California Potential hazards from future eruptions in the vicinity of Mount Shasta Volcano, Northern California
Mount Shasta has erupted, on the average, at least once per 800 years during the last 10,000 years, and about once per 600 years during the last 4,500 years. The last known eruption occurred about 200 radiocarbon years ago. Eruptions during the last 10,000 years produced lava flows and domes on and around the flanks of Mount Shasta, and pyroclastic flows from summit and flank vents...
Authors
C. Dan Miller
A plotting program for producing ashfall prediction maps from the output of the NOAA forecast trajectory program; application to and examples from the 1980 Mount St. Helens eruptions A plotting program for producing ashfall prediction maps from the output of the NOAA forecast trajectory program; application to and examples from the 1980 Mount St. Helens eruptions
No abstract available.
Authors
William K. Smith