The Bransfield Strait is the narrow, late Tertiary to Quaternary marginal basin separating the South Shetland Islands from the northern end of the Antarctic Peninsula magmatic arc. Quaternary volcanism in the strait is tholeiitic to mildly alkaline, and contrasts chemically with the pre-Quaternary calc-alkaline arc volcanism. Geochemical evidence presented here...
Volcanic rocks from hotspots and island arcs/backarcs typically have enriched trace
element and isotopic compositions that contain a contribution from subducted oceanic crust.
Isotopic and trace element data suggest that the enriched components in hotspot volcanism
are ancient subducted sediment and crust, and the enriched components in arc/backarc
volcanism are...
The current thesis presents contingent valuation research incorporating social psychological measures that investigates recreationists' willingness to pay recreation access fees at McDonald-Dunn Forest, Oregon. Context is provided through an extensive literature review of recreation fee management, issues and concerns related to recreation fees, recreationists' attitudes toward fees, relevant social psychological...
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Randall S. Rosenberger
The current thesis presents contingent valuation research
The endangered Hawaiian Duck (koloa maoli; Anas wyvilliana), a non-migratory and island-endemic species, experienced a significant population decline during the twentieth century due to factors such as habitat loss, overharvest, introduced mammalian predators, and hybridization with introduced feral Mallards (A. platyrhynchos). A key objective for Hawaiian Duck recovery is to...
The global mid-ocean ridge system is the largest magmatic system encompassing over 75% of the Earth’s total volcanism. As magmas ascend through the vertically variable oceanic crust, melts begin to crystallize and diversify and subsequently erupt at the surface. The interpretation of these erupted products observed on the seafloor requires...
The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall concrete dam on the Calapooia River, Oregon, was removed in...
The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. Improvements in instrumentation, sample preparation methods, and new material obtained by recent drilling...
The Cobb Seamount Chain in the northeast Pacific basin records the composition of the Cobb hot spot for the past 33 Myr, as the migrating Juan de Fuca Ridge approached and ultimately overran it ca. 0.5 Myr ago. In this first comprehensive geochemical study of the Cobb chain, major and...
Full-coverage multibeam bathymetric mapping of twelve seamounts in the Gulf of Alaska reveals that
they are characterized by flat-topped summits (rarely with summit craters) and by terraced, or step-bench,
flanks. These summit plateaus contain relict volcanic features (e.g., flow levees, late-stage cones, and
collapse craters) and as such must have...
Previous work has developed the What You See Is What You Test (WYSIWYT) methodology for testing spreadsheets. This methodology has been shown to help end users test, debug, and modify spreadsheets. To date, however, this system has provided no support for creating, reusing, and managing test cases, a process that...
