Publications
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Calc-alkaline, shoshonitic, and primitive tholeiitic lavas from monogenetic volcanoes near Crater Lake, Oregon
Quaternary monogenetic volcanism in the High Cascades of Oregon is manifested by cinder cones, lava fields, and small shields. Near Crater Lake caldera, monogenetic lava compositions include: low-K (as low as 0·09% K2O) high-alumina olivine tholeiite (HAOT); medium-K. calc-alkaline basalt, basaltic andesite, and andesite; and shoshonitic basaltic andesite (2·1% K2O, 1750 ppm Sr at 54% SiO2). Thole
Authors
Charles R. Bacon
Chapter 14: Middle Cretaceous silicic metavolcanic rocks in the Kings Canyon area, central Sierra Nevada, California
Metamorphosed silicic volcanic and hypabyssal rocks of middle Cretaceous (110 to 100 Ma) age occur in two roof pendants in the Kings Canyon area of the central Sierra Nevada. The metavolcanic remnants are similar in age to or are only slightly older than the voluminous enclosing batholithic rocks. Thus, high to surface levels of the batholith are implied for this region. This is interesting consid
Authors
J.B. Saleeby, R. W. Kistler, Samuel Longiaru, James G. Moore, Warren J. Nokleberg
Reef growth and volcanism on the submarine southwest rift zone of Mauna Loa, Hawaii
A marine sampling program, utilizing the PISCES-5 submersible operated by the Hawaii Undersea Research Laboratory (NOAA), has confirmed the presence of a major submerged coral reef offshore from Ka Lae (South Point), Hawaii. The top of the reef is now 150–160 m below sea level. Radiocarbon and Useries dating indicates that it drowned about 13.9 ka by the combined effects of island subsidence (2.5
Authors
James G. Moore, W. R. Normark, B. J. Szabo
Subsidence and volcanism of the Haleakala Ridge, Hawaii
Side-looking sonar (GLORIA) mapping has revealed a series of four arcuate bands of high sonic backscatter on the crest of the Haleakala Ridge, a major rift-zone ridge extending 135 km east of the island of Maui. Dredge recovery indicates that the shallowest of these bands is a drowned coral reef, and the deeper bands are also inferred to be coral reefs. The reefs occur above a prominent submarine
Authors
James G. Moore, D. A. Clague, K. R. Ludwig, R. K. Mark
Monitoring the hydrologic system for potential effects of geothermal and ground-water development in the Long Valley caldera, Mono County, California, U.S.A.
In the early 1980's, renewed interest in the geothermal potential of the Long Valley caldera, California, highlighted the need to balance the benefits of energy development with the established recreational activities of the area. The Long Valley Hydrologic Advisory Committee, formed in 1987, instituted a monitoring program to collect data during the early stages of resource utilization to evaluat
Authors
C. D. Farrar, D. L. Lyster
Lava domes modeled as brittle shells that enclose pressurized magma, with application to Mount St. Helens
No abstract available.
Authors
R. M. Iverson
A new tree-ring date for the "floating island" lava flow, Mount St. Helens, Washington
Anomalously narrow and missing rings in trees 12 m from Mount St. Helens' "floating island" lava flow, and synchronous growth increases in trees farther from the flow margin, are evidence that this andesitic flow was extruded between late summer 1799 and spring 1800 a.d., within a few months after the eruption of Mount St. Helens' dacitic layer T tephra. For ease of reference, we assign here an 18
Authors
D.K. Yamaguchi, R. P. Hoblitt, D.B. Lawrence
A decade of dome growth at Mount St. Helens, 1980-90
The growth of the dacite dome at Mount St. Helens between 1980 and 1986 has been more intensively studied than that of any other dome-building eruption. The growth has been complex in detail, but remarkably regular overall. This paper summarizes some of what has been learned and provides many references to additional information. Whether dome building has ended is an open question, particularly in
Authors
D. A. Swanson
Rhyolitic calderas of the Yukon-Tanana Terrane, east central Alaska: volcanic remnants of a mid-Cretaceous magmatic arc
Four large but poorly exposed rhyolitic calderas are present in the Yukon-Tanana terrane (YTT) in east central Alaska. At least two are mid-Cretaceous in age (~93 Ma). Similar volcanic rocks, the South Fork Volcanics, occur northeast of the Tintina fault in Yukon Territory. Evidence for the calderas consists of thick deposits of devitrified crystal- and lithic-rich densely welded tuff, interpreted
Authors
C. R. Bacon, H.L. Foster, James G. Smith
The eruption of Redoubt Volcano, Alaska, December 14, 1989-August 31, 1990
No abstract available.
Authors
Thomas J. Casadevall, Bernard A. Chouet, John N. Davies, Steven A. Estes, Cynthia A. Gardner, Richard P. Hoblitt, John C. Lahr, Richard G. Lahusen, Jon J. Major, Robert G. McGimsey, Thomas P. Miller, Thomas L. Murray, Christina A. Neal, Christopher J. Nye, Robert A. Page, Thomas C. Pierson, John Power, Christopher D. Stephens, Richard B. Waitt