I examined the relative roles of biotic and abiotic factors in structuring redband trout
Oncorhynchus mykiss distributions in the South Fork John Day. I first examined the
relationship between the biological traits of the fish assemblage and riparian-geomorphic features in context of prevailing theories of stream ecology stemming from the...
Basaltic volcanism provides a window into the Earth’s mantle. Seeing through this window requires seeing through the processes of magma genesis and evolution that distort the view. Radiogenic isotope ratios, and to a lesser extent incompatible elements and stable isotope ratios, allow us to see through these distortions and infer...
The response of adjacent structural systems to earthquake motions is investigated using the finite element framework OpenSees. Results of sensitivity analyses demonstrate that structural response quantities can increase in either or both of the adjacent structures for specific configurations. The structural models used include steel moment-resisting frames and rigid shear...
The two classic theories of the distribution of
cities in an urban system are the rank size rule
and central place theory. The rank size relationships,
as incorporated into G. K. Zipf's Principle
of Least Effort, is seen as the result of a balancing
of the opposing forces of urban...
Columbia River sediment was irradiated with ultraviolet light to
determine if organic material could be removed without altering the
sorptive properties of the hydrous oxides of iron and manganese.
A laboratory preparation of Zn-65 spiked hydrous ferric oxide
was subjected to ultraviolet irradiation in order to assess the photochemical
effect...
We report new major element, trace element, isotope ratio, and geochronological data on the Galapagos
Archipelago. Magmas erupted from the large western volcanos are generally moderately fractionated tholeiites of
uniform composition; those erupted on other islands are compositionally diverse, ranging from tholeiites to picritic
basanitoids. While these volcanoes do not...