Columbia River Basalt Group dikes cut the tonalite-granodiorite Wallowa Batholith in northeastern Oregon, providing a natural setting in which to examine partial melting. Many dikes have up to 5 m-wide zones of quenched partially melted wallrock at their margins. This paper examines the progressive partial melting reactions in biotite-and hornblende-bearing...
The primary goal of this study is to assess the impact of a subduction component
added to the mantle wedge beneath the Oregon Cascades to the composition and fO2 of
primitive Cascade basalts. Olivine-hosted melt inclusions from compositionally diverse
basalts across the Cascade arc (~100 km) are utilized in an...
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lavas where
volcanic gasses are lost during eruption.
In this study we report an example of Fe
Heterogeneous catalysis modulates the rate and selectivity of reaction processes by
stabilizing a series of intermediate states on solid surfaces, facilitating the production
of many commodity chemicals modern society relies upon. Conventional, thermal
catalytic processes—conducted at elevated temperatures and pressures—source
thermal, mechanical, and chemical potential energy from carbon-hydrogen bonds—
combustion...
The intricate relationship between wildlife health and the quality of their environment is well established, with technological advances increasing our understanding and aiding the unraveling of underlying mechanisms. Large herbivores require forage of sufficient quality to maintain their condition to reproduce and survive, all while warding off parasites and predators...
Riparian zones are ecotones between terrestrial and aquatic ecosystems. Processes in streams are strongly influenced by riparian forest communities, age, stage and structure. Temperate forests across much of North America, including riparian areas, are recovering from historic land clearing with many stands in the stem-exclusion phase of development in which...
Clostridium perfringens is the causative agent of a wide variety of diseases in animals and humans. C. perfringens can produce more than 15 toxins. However, individual strains produce a subset of these toxins. Although a small percentage of C. perfringens isolates (mostly belonging to type A) produce C. perfringens enterotoxin...
This dissertation uses a new methodological approach for an in-depth analysis of three cartographic works. Studies within the discipline of the history of cartography have followed various methodologies throughout the past century. This dissertation argues that in order to come to a more complete understanding of how maps were produced...
Modern upwelling conditions and corresponding oceanographic properties are investigated and reconstructed for the Late Quaternary. The oceanographic conditions considered influence diatom ecology and the record of fossil diatom frustules in the sediments.
Diatoms from modern sediments are evaluated as paleoceanographic proxies and transfer functions (TFs) are calibrated using the Imbrie...