Download or read book Trace Elements in High Cascade Volcanic Rocks written by Gary Jacob Anttonen and published by . This book was released on 1972 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Trace Element Geochemistry of Several Volcanic Centers in the High Cascades written by Terry Laurence Steinborn and published by . This book was released on 1972 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petrography and Petrology of Volcanic Rocks in the Mount Jefferson Area High Cascade Range Oregon written by Robert C. Greene and published by . This book was released on 1968 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geochemical Analyses Age Dates and Flow volume Estimates for Quaternary Volcanic Rocks Southern Cascade Mountains Washington written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Data collected over the last three years as part of a continuing study of the Quaternary volcanic rocks of the southern Cascade Mountains are presented. Whole-rock chemical analyses, selected trace element geochemistry, volume approximations, specific gravity determinations, and locations are provided for most of the 103 samples collected, and 21 radiometric age dates are included. In addition, partial information, including names and flow-volumes, are presented for 98 additional samples, collected for related studies. The study extends from the Columbia River north to the Cowlitz River and Goat Rocks Wilderness area, and from the Klickitat River west to the Puget-Willamette Trough. The volcanic rocks are all younger than 3 million years and consist primarily of tholeiitic and high-alumina basalts and basaltic-andesites erupted from numerous shield volcanoes and cinder cones. A few analyses of more silicic rocks, including hornblende and/or pyroxene andesites and dacites characteristic of the stratovolcanoes of the region, are also presented. However, systematic sampling of the stratovolcanoes in the study area, Mount Adams and Mount St. Helens, was not conducted. A map of the areal extent of Quaternary volcanic units and sample locations is included. It has been based on the 1:125,000 reconnaissance geologic map of the southern Cascade Range by Hammond (1980).
Download or read book Trace Element Geochemistry of Volcanic Rocks written by D. A. Wyman and published by . This book was released on 1996 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petrogenesis of Compositionally Distinct Silicic Volcanoes in the Three Sisters Region of the Oregon Cascade Range written by Brittain E. Hill and published by . This book was released on 1991 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Three Sisters region of the Oregon High Cascades has developed three compositionally and petrogenetically distinct silicic (i.e., SiO2 [greater than or equal to] 58%) magma systems within the last 600 k.y. These silicic systems evolved from the same High Cascade mafic magma system and developed in the same 20x30 km area of the arc, but did not interact. The Broken Top system (BT) evolved to 71% SiO2 through a combination of plag + px + Fe-Ti oxides ± ap (PPFA) fractionation and 20%-35% mixing of rhyolitic (74% SiO2) crustal melts. In contrast, part of the Three Sisters system (3S) evolved to 66% SiO2 through PPFA fractionation alone, while other parts evolved to 66% SiO2 through PPFA fractionation coupled with [greater than or equal to} 40% mixing of rhyolitic ([greater than or equal to]72% SiO2) crustal melts. The 3S system was intermittently active from [less than or equal to] 340 ka to 2 ka. The petrogenesis of intermediate composition rocks at Middle Sister (340 ka, 100 ka) was controlled by PPFA fractionation to [less than or equal to] 66% SiO2. Rhyolite (72%-76% SiO2) was first erupted in the 3S system at [approximately] 100 ka, at the start of South Sister (SS) volcanism. Major and trace element abundances preclude derivation of 3S rhyolite through crystal fractionation, but are consistent with 20-30% dehydration melting of mafic amphibolite. The petrogenesis of intermediate composition rocks at SS was controlled by PPFA fractionation coupled with 30-40% rhyolitic magma mixing. However, the rhyolitic magma mixed into an essentially mafic system, which limited intermediate differentiation at SS to [less than or equal to] 66% SiO2. The BT system was active from [approximately] 600 ka to at least 200 ka. Major and trace element abundances preclude derivation of BT rhyolite (74% SiO2) through crystal fractionation, but are consistent with [approximately] 30% dehydration melting of older tonalitic intrusions. BT petrogenesis was controlled by PPFA fractionation accompanied by 10-20% mixing of rhyolitic magmas to [approximately] 63% SiO2, with [approximately] 30% rhyolite mixing from 63% to 71% SiO2. In contrast to the 3S system, differentiation proceeded beyond 66% SiO2 because rhyolitic magma was mixed into a more evolved ([approximately] 60%-65% SiO2) system. The observed temporal and spatial variations in petrogenesis were not controlled by regional changes in tectonic setting, crustal thickness or crustal composition. However, small-scale changes in the magnitude of crustal extension occurred in this area, and are thought to have controlled petrogenesis by localizing mid-crustal mafic magmatism and thus crustal heat flow.
Download or read book Geological Survey Professional Paper written by and published by . This book was released on 1972 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Trace Elements in Igneous Petrology written by C.J. Allègre and published by Elsevier. This book was released on 2013-10-22 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Trace Elements in Igneous Petrology, 5: Developments in Petrology: A Volume in Memory of Paul W. Gast focuses on the contributions and influence of Gast in petrology, including crystallization, magmatic processes, isotopic composition, and ocean ridge basalt chemistry. The selection first takes a look at quantitative models of trace element behavior in magmatic processes; application of trace elements to the petrogenesis of igneous rocks of granitic composition; and an assessment of local and regional isotopic equilibrium in the mantle. Discussions focus on evidence derived from time constraints, scale of isotopic disequilibrium, fractional crystallization, trace element modeling, geodynamics and tectonic setting, partition coefficients, quantitative models for trace elements, and parameter determination and inverse-problem solution. The publication then examines the isotopic composition of lead in oceanic basalt and its implication to mantle evolution; strontium isotopes in basalts from the Pacific Ocean basin; and trace elements in ocean ridge basalts. Concerns cover variations in ocean ridge basalt chemistry, trace elements in ocean ridge basalts, disequilibrium partial melting, seawater alteration, background for lead isotope tracer studies, and uranium, thorium, and lead concentrations in basalts. The book examines trace elements and anorthosite genesis, lead isotopes in Archaean plutonic rocks, early Archaean rocks and geochemical evolution of the earth's crust, and factors controlling the noble gas abundance patterns of deep-sea basalts. The selection is a valuable source of data for researchers interested in petrology.
Download or read book Trace Elements in Magmas written by Denis M. Shaw and published by Cambridge University Press. This book was released on 2006-03-09 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book brings together the essential theory required to understand the behaviour of trace elements in magmas and magma-derived rocks.
Download or read book Water resources Investigations Report written by and published by . This book was released on 1998 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Geological Survey Bulletin written by and published by . This book was released on 1983 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water quality and Algal Conditions in the North Umpqua River Basin Oregon 1992 95 and Indications for Resource Management written by Chauncey W. Anderson and published by . This book was released on 1998 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Publications of the U S Geological Survey written by and published by . This book was released on 1990 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by United States. Superintendent of Documents and published by . This book was released on 1966 with total page 1320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Publications of the Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 1989 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geological Studies in the Klamath Mountains Province California and Oregon written by Arthur W. Snoke and published by Geological Society of America. This book was released on 2006-01-01 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accompanying CD-ROM includes additional images and maps.
Download or read book New Publications of the U S Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 1990 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:
