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Geodetic Gps Measurements In South Iceland: Strain Accumulation And Partitioning In A Propagating Ridge System, P. C. Lafemina, Timothy H. Dixon, R. Malservisi, T. Arnadottir, E. Sturkell, F. Sigmundsson, P. Einarsson Nov 2005

Geodetic Gps Measurements In South Iceland: Strain Accumulation And Partitioning In A Propagating Ridge System, P. C. Lafemina, Timothy H. Dixon, R. Malservisi, T. Arnadottir, E. Sturkell, F. Sigmundsson, P. Einarsson

School of Geosciences Faculty and Staff Publications

GPS observations in south Iceland between 1994 and 2003 are compared with two-dimensional elastic half-space and viscoelastic coupling models for two parallel rift zones, representing the Western and Eastern volcanic zones (WVZ, EVZ). GPS data from the Hreppar block, between the WVZ and EVZ, fit a rigid block model within uncertainties. Spreading rates across the WVZ increase from 2.6 ± 0.9 mm/yr in the northeast to 7.0 ± 0.4 mm/yr in the southwest. Conversely, spreading rates in the EVZ decrease from 19.0 ± 2.0 mm/yr in the northeast to 11.0 ± 0.8 mm/yr in the southwest, the direction of ridge …

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Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin Sep 2005

Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin

Theses and Dissertations

The Golden Throne Quadrangle is located within Capitol Reef National Park, south-central Utah. Geologic mapping of this 1:24,000 scale 7.5 minute quadrangle began in 2003 as the National Parks Service desired to have geologic maps at this scale produced within the park. Stratigraphically, ten bedrock formations and ten Quaternary deposits are exposed within the Golden Throne Quadrangle. Geologic formations range in age from Permian to Jurassic. This map contains details not included on previous geologic maps including; the members of the Carmel, Chinle, and Moenkopi Formations. Additionally, the Page Sandstone is herein mapped as an independent unit. Structurally the Golden …

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Bibliography Of New Mexico Invertebrate Paleontology, Barry S. Kues Aug 2005

Bibliography Of New Mexico Invertebrate Paleontology, Barry S. Kues

Earth and Planetary Sciences Faculty and Staff Publications

Bibliography contains citations for published papers on New Mexico invertebrate paleontology from 1848 to 2004

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A Geodetic Investigation Of Ground Deformation At Yucca Mountain, Southern Nevada, Emma Mccaughey Aug 2005

A Geodetic Investigation Of Ground Deformation At Yucca Mountain, Southern Nevada, Emma Mccaughey

Publications (YM)

The data from 28 continuous BARGEN GPS stations in the Yucca Mountain region were processed for January 2000 to June 2004. The data have been processed independently using both the GIPSY and GAMIT software packages for quality assurance purposes, yielding an RMS of velocity differences between the solutions of 0.06 mm/yr for the east and 0.10 mm/yr for the north. The velocity solution for the local Yucca Mountain network has a relatively smooth signal showing NW-trending rightlateral shear. The magnitude of the velocity contrast across the local network, from east to west, is 0.95 ± 0.04 mm/yr. The GPS results …

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Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson Jul 2005

Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson

Theses and Dissertations

Hydrogeologically important features of fault zones include undamaged country rock, the damage zone, and the core zone. Fault cores generally have low porosity and permeability, and often act as a barrier to groundwater flow. The damage zone, by contrast, consists of small faults and fracture networks, which can act as conduits. Timpoweap Canyon near Hurricane, Utah has superb exposures of the fault core and damage zone of the Hurricane Fault. Also within the canyon, springs discharge from the damage zone into the Virgin River, providing an ideal natural laboratory for the study of groundwater discharge from a fault zone. The …

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Upper Mantle Reflectivity Beneath An Intracratonic Basin: Insights Into The Behavior Of The Mantle Beneath Illinois Basin., Maxwell Sunday Okure Jun 2005

Upper Mantle Reflectivity Beneath An Intracratonic Basin: Insights Into The Behavior Of The Mantle Beneath Illinois Basin., Maxwell Sunday Okure

Theses and Dissertations

Reflectivity images of the lower crust and uppermost mantle beneath the Illinois basin have been derived from reprocessing of several hundred kilometers of industry seismic reflection data using extended vibroseis recorrelation. The recorrelation was based on extending an originally 4-s correlated record, acquired with a 16-s sweep from 14 to 126 Hz, to the absolute limit of the full 20 s (~70 km) listening travel time. The reconstructed bandwidth includes frequency components suitable for imaging structures from signals received from both sedimentary basin reflectors and those received from reflectors in the deep crust and upper mantle. Mantle and sub-Moho reflectors …

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Absent Homosexuality: The Mediated Discourses Of Masculinity On The Design And Construction Of The Sydney Opera House, Greg Young Jun 2005

Absent Homosexuality: The Mediated Discourses Of Masculinity On The Design And Construction Of The Sydney Opera House, Greg Young

Journal of International Women's Studies

This paper examines the controversy surrounding the construction of the Sydney Opera House at mid-century, and the role of “absent” homosexuality in shaping the new ideals of the country as a modern nation. Australian popular culture--in this instance, the Opera House--is an example of “feminine” culture being incorporated into what had hitherto been a masculinist Australian civic identity. The public discourse surrounding the opera house reveals clear anxieties regarding gender and sexuality in Australia in the 1950s, and the inherently unstable narratives of gender and sexuality under Australian patriarchy from the 19th century onwards. Henning Bech’s notion of “absent homosexuality” …

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Evaluation Of Coalbed Methane Resource Potential Using Limited Data, Oluwabiyi Michael Olaniran May 2005

Evaluation Of Coalbed Methane Resource Potential Using Limited Data, Oluwabiyi Michael Olaniran

Engineering

This study presents the results of the evaluation of the Coalbed Methane (CBM) resource potential of the Cook Inlet Basin using a computer-aided well log analysis of the subsurface data. Coal seams were identified from the well logs. Formation and reservoir fluid properties including porosity, water saturation and net pay thickness of the coal seams were determined. The analysis revealed discontinuous coal seams interspaced largely by mudstone, silt, and sandstone formations within the depth of investigation. The CBM resource (Original Gas In Place) and recoverable reserves were estimated on per acre-foot basis. Monte Carlo simulation was run to refine the …

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The Caves And Karst Of Rota Island, Commonwealth Of The Northern Mariana Islands, Thomas M. Keel May 2005

The Caves And Karst Of Rota Island, Commonwealth Of The Northern Mariana Islands, Thomas M. Keel

Theses and Dissertations

Rota Island, the southernmost island in the Commonwealth of the Northern Mariana Islands in the western Pacific, has the types of caves previously documented on the other limestone mantled islands in the Mariana Arc that have been investigated for caves: Aguijan, Guam, Tinian and Saipan. Caves developed at the edge of the fresh-water lens by zones of enhanced carbonate dissolution produced by fresh-water/salt-water mixing are most common. Among these mixing zone caves, flank margin caves dominate. Flank margin caves were found singly and in extensive horizons representing significant sea-level still stands. However, another type of mixing zone cave was found …

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Port Jefferson Geomorphology, Danielle. Mulch, Gilbert N. Hanson Apr 2005

Port Jefferson Geomorphology, Danielle. Mulch, Gilbert N. Hanson

Long Island Geologists' Abstracts

Program for the Twelfth Conference on Geology of Long Island and Metropolitan New York

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Cave Talk, April 2005, Susan Berdeaux Apr 2005

Cave Talk, April 2005, Susan Berdeaux

Cave Talk

Contents: Six NCA Caves Designated By National Geographic -- 2005 National Cave And Karst Management Symposium -- Paul Rubin Joins Howe Caverns Staff -- Cave License Plates? -- Year of the Cave -- Convention 2005 -- Is It Info Or Is It Spam? -- Penny for Your Thoughts? -- NCA Board of Directors Meeting -- Insurance Update -- NCA Insurance Committee -- Crisis Guide -- Final Thoughts Mid-Winter Meeting February 26, 2005 -- Join the NCA Insurance Program! Steps to Becoming a Member of the NCA Insurance Program

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2005 Seventeenth Annual Imsa Presentation Day, Illinois Mathematics And Science Academy Apr 2005

2005 Seventeenth Annual Imsa Presentation Day, Illinois Mathematics And Science Academy

IMSAloquium Event Booklets

"The Student Inquiry and Research Program fosters the development of students as highly skilled and integrative problem finders, problem solvers, and apprentice investigators, all skills required to succeed in the global workplace of the 21" Century."

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A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …

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Report Of The Working Group On Deep-Water Ecology (Wgdec), 8-11 March 2005, Jm Hall-Spencer Mar 2005

Report Of The Working Group On Deep-Water Ecology (Wgdec), 8-11 March 2005, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant Mar 2005

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …

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Topographic Complexity And Benthic Community Variability Within A Kelp Forest In Monterey Bay, Ca : A Thesis ..., Eric J. Sandoval Jan 2005

Topographic Complexity And Benthic Community Variability Within A Kelp Forest In Monterey Bay, Ca : A Thesis ..., Eric J. Sandoval

Capstone Projects and Master's Theses

By understanding species and habitat associations, predictions of species composition can be made about a benthic community based on available habitat. In a kelp forest, topographic complexity can affect an organism, by modifying flow, altering food availability, altering light availability, and provide refuges and barriers that fragment the habitat. There are many qualitative ways to evaluate topographic complexity. Rugosity is a quantitative measure and is defined as the ratio of surface area to planar area. Using habitat maps developed in GIS from multibeam bathymetry data, regions of varying rugosity were mapped in southern Monterey Bay, CA. Associated benthic communities were …

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Sedimentary Environments Of East And West Flower Garden Banks Area, Kathryn M. Scanlon, Seth D. Ackerman, Jill E. Rozycki Jan 2005

Sedimentary Environments Of East And West Flower Garden Banks Area, Kathryn M. Scanlon, Seth D. Ackerman, Jill E. Rozycki

Gulf of Mexico Science

No abstract provided.

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Geology Of Centennial Valley And Stratigraphy Of Pleistocene Fossil-Bearing Sediments, Christopher L. Hill Jan 2005

Geology Of Centennial Valley And Stratigraphy Of Pleistocene Fossil-Bearing Sediments, Christopher L. Hill

Anthropology Faculty Publications and Presentations

This paper is based on stratigraphic studies conducted at the Merrell Locaility and other locations in Centennial Valley. The Merrell Locality is situated in southwest Montana, on the western end of Centennial Valley (Figure 30). It is notable for containing the fossil vertebrate remains of mammoth (Mammuthus cf. M. columbi), scimitar cat (a member of the sabretooths, Homotherium serum), horse (Equidae) and Yesterday's camel (Camelops cf. hesternus), as well as other plant and animal fossils of Pleistocene age (Dundas 1990; Dundas, Hill, and Batten 1996). Summaries and reports of research conducted at the locality include …

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Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto Jan 2005

Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Brazilian Tapajós gold province contains the first evidence of high-sulfidation gold mineralization in the Amazonian Craton. The mineralization appears to be in large nested calderas. The Tapajós–Parima (or Ventuari–Tapajo´ s) geological province consists of a metamorphic, igneous, and sedimentary sequence formed during a 2.10 to 1.87 Ga ocean ̶ continent orogeny. The high-sulfidation mineralization with magmatic-hydrothermal alunite is related to hydrothermal breccias hosted in a rhyolitic volcanic ring complex that contains granitic stocks ranging in age from 1.89 to 1.87 Ga. Cone-shaped hydrothermal breccias, which flare upward, contain vuggy silica and have an overlying brecciated cap of massive silica; …

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Dye Tracing Recharge Features Under High-Flow Conditions, Onion Creek, Barton Springs Segment Of The Edwards Aquifer, Hays County, Texas, Brian B. Hunt Jan 2005

Dye Tracing Recharge Features Under High-Flow Conditions, Onion Creek, Barton Springs Segment Of The Edwards Aquifer, Hays County, Texas, Brian B. Hunt

KIP Data Sets and Technical Reports

The Barton Springs/Edwards Aquifer Conservation District, in cooperation with the City of Austin, injected non-toxic organic dyes into two caves within the Barton Springs segment of the Edwards aquifer to trace groundwater flow paths and determine groundwater-flow velocities. Antioch and Cripple Crawfish Caves are located about 14.0 and 17.5 miles south, respectively, of Barton Springs, the primary discharge point from the aquifer. Twenty-five pounds of sodium fluorescein were injected into Antioch Cave on August 2, 2002 and arrived at Barton Springs between 7 to 8 days after the injection. Thirty-five pounds of eosine were injected into Cripple Crawfish Cave on …

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Paradigms Of Positive Change: Reordering The Nation's Land Use System, John R. Nolon Jan 2005

Paradigms Of Positive Change: Reordering The Nation's Land Use System, John R. Nolon

Elisabeth Haub School of Law Faculty Publications

This article begins with a brief look at the system’s familiar dysfunctions, continues with a lengthier examination of positive examples of reform, emphasizes the importance of coalition building in the reform process, and ends with the observation that reform efforts should be organized by the task of creating essential connections among the governments involved.

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National Cave And Karst Research Institute 2004-2005 Annual Report, National Cave And Karst Research Institute Jan 2005

National Cave And Karst Research Institute 2004-2005 Annual Report, National Cave And Karst Research Institute

KIP Articles

No abstract provided.

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The Silver Spring And Blackrock Faults, East-Central Nevada: Kinematics, Timing, And Role Of Low-Angle Normal Faulting In The Development Of Railroad Valley, Tyler R Knudsen Jan 2005

The Silver Spring And Blackrock Faults, East-Central Nevada: Kinematics, Timing, And Role Of Low-Angle Normal Faulting In The Development Of Railroad Valley, Tyler R Knudsen

UNLV Retrospective Theses & Dissertations

The structural development of Railroad Valley, a large and economically important Tertiary basin in east-central Nevada, has been the focus of much debate. This study addresses many of the points of controversy through a detailed geologic study of structures in the southwestern White Pine Range; Detailed geologic mapping and construction of cross-sections reveal both low- and high-angle normal faults. The low-angle faults consist of three bedding-parallel faults, two top-to-the-southwest and one top-to-the-south, and two large displacement (>8 km heave) (26,000 ft) top-to-the-west detachments that denude a range-scale Mesozoic fold. Two spatially distinct groups of high-angle normal faults are present: …

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The Role Of Transverse Faults In Great Basin Extension: Transfer Faults Or N-S Extension?, Tandis S Bidgoli Jan 2005

The Role Of Transverse Faults In Great Basin Extension: Transfer Faults Or N-S Extension?, Tandis S Bidgoli

UNLV Retrospective Theses & Dissertations

New geologic map data (1:24,000 scale), geometric analyses, and kinematic analyses in the vicinity of the Crescent Spring fault zone (CSFZ), an E-W-striking fault zone in eastern Nevada, allow the recognition of four distinct extensional episodes. The episodes are pre-volcanic (pre-27 Ma), syn-volcanic (∼27-18 Ma), Miocene (?) post-volcanic, and Miocene (?) - Pliocene or Quaternary post-volcanic extension. This extensional pattern, which is consistent with other fault studies along the broadly defined Timpahute lineament, has several important aspects. (1) Transverse faults of the CSFZ are normal faults that accommodated a distinct N-S extensional event. (2) The strain field within this part …

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Petrogenesis And Geochemistry Of Pleistocene And Pliocene Basalt Flows Of The Pine Valley Volcanic Field, Utah And Their Relationship To The Tectonics Of The Utah Transition Zone, Matthew Faust Jan 2005

Petrogenesis And Geochemistry Of Pleistocene And Pliocene Basalt Flows Of The Pine Valley Volcanic Field, Utah And Their Relationship To The Tectonics Of The Utah Transition Zone, Matthew Faust

UNLV Retrospective Theses & Dissertations

The Pine Valley Volcanic Field in southwestern Utah consists of at least 24 mafic lava flows and 10 vents. Eruptions have spanned the past 2.4 m.y. The youngest eruptions at the Snow Canyon and Diamond Valley cones occurred between 1 and 20 ka. Lava flows range in composition from basalt to andesite, and include both alkaline and subalkaline rocks throughout the field. Trace element abundances for the youngest lavas show both oceanic island basalt (OIB) and mid-oceanic ridge basalt (MORB) components in their source. Sr and Nd isotopic ratios exhibit evolved values, spanning a large range from epsilon Nd of …

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Geologic Map And Topographic Profile Of The Newark Quadrangle, Nebraska, Steven M. Condon Jan 2005

Geologic Map And Topographic Profile Of The Newark Quadrangle, Nebraska, Steven M. Condon

United States Geological Survey: Publications

Newark Quadrangle, Nebraska

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Geologic Map And Topographic Profile Of The Elm Creek West Quadrangle, Nebraska, Steven M. Condon Jan 2005

Geologic Map And Topographic Profile Of The Elm Creek West Quadrangle, Nebraska, Steven M. Condon

United States Geological Survey: Publications

Geologic Map and Topographic Profile of the Elm Creek West Quadrangle, Nebraska

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Geologic Studies Of The Platte River, South-Central Nebraska And Adjacent Areas—Geologic Maps, Subsurface Study, And Geologic History, Steven M. Condon Jan 2005

Geologic Studies Of The Platte River, South-Central Nebraska And Adjacent Areas—Geologic Maps, Subsurface Study, And Geologic History, Steven M. Condon

United States Geological Survey: Publications

The Platte River of south-central Nebraska was studied at three scales to place the river in its geological context and to trace its evolution through geologic time. At the largest scale the Elm Creek West and the Newark 7.5 minute quadrangles were mapped. These quadrangles are located just west and just east of Kearney and serve to illustrate the main geomorphic elements of the present Platte River Valley. The central elements of the quadrangles are the Platte River channels, islands, and bottomlands, which are flanked by terraces that step up away from the river to the north and south. Significant …

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Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed Jan 2005

Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Typical porphyry-type Cu–Mo mineralization occupies two connected domal centers, the eastern Pittsmont and western Anaconda domes, that predate and largely underlie the well-known, throughgoing, Main Stage polymetallic veins of Butte. Among the sulfur-bearing minerals recovered from deep drill core of this early pre-Main Stage hydrothermal assemblage are anhydrite, chalcopyrite, pyrite, and molybdenite in veinlets bordered by K-silicate alteration, and pyrite from slightly younger quartz–pyrite veinlets with dgray-sericiticT alteration selvages. The ranges of δ34S values for minerals of the K-silicate assemblage are 9.8–18.2%◦ for anhydrite (n=23 samples), 3.0%◦ to 4.7%◦ for molybdenite (n=6), 0.4%◦ to 3.4%◦ for pyrite (n=19), …

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Chromian Spinel–Olivine Phase Chemistry And The Origin Of Primitive Basalts Of The Southern Washington Cascades, Diane R. Smith, W. P. Leeman Jan 2005

Chromian Spinel–Olivine Phase Chemistry And The Origin Of Primitive Basalts Of The Southern Washington Cascades, Diane R. Smith, W. P. Leeman

Earth and Environmental Geosciences Faculty Research

Geochemically diverse basalts occur in an ~160-km-wide transect that stretches across the Quaternary southern Washington Cascades (SWC) volcanic arc. Two fundamental groups of SWC basalts can be identified on the basis of major and trace element chemistry. On primitive mantle-normalized “spidergrams”, Group I lavas resemble within-plate basalts, whereas Group II lavas exhibit chemical characteristics (e.g., Nb, Ta, and Ti depletions) typical of subduction-related magmas. The primitive nature of many SWC basalts is indicated by their high MgO (>6.5 wt.%, up to 9.5 wt.%), Ni (>85 ppm) and Cr (>180 ppm) contents. Electron microprobe analyses of olivine–spinel pairs …

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