The magnitude, seasonality, and duration of peak discharge responses to forest removal and regrowth and roads in 10 pairs of experimental basins in the western Cascade Range of Oregon are consistent with fundamental water balance and routing concepts in hydrology. Hypothesized effects of forestry treatments on evapotranspiration, cloud water interception,...
Since their discovery in 1977, hydrothermal vent communities have offered scientists
a unique glimpse into a world that is supported primarily by chemically derived
energy rather than direct energy from the sun. Furthermore, studies of hydrothermal
vent ecosystems have introduced scientists to amazing animals that have successfully
adapted to living...
This thesis presents a hydrogeologic study of the Parrett Mountain Region,
located approximately 20 miles south of Portland, Oregon. The aim of the study was
to investigate the impacts of Columbia River Basalt on the regional groundwater
system, to expand our understanding of flow through fractured basalt, to improve
management...
This study investigates riparian cover change between 1939 and 1996 utilizing aerial
photography, bank conditions and stream gauge data. Three sites under 1.0 km2, along a 10-
km reach north of Harrisburg, Oregon, were evaluated. The cover classification scheme
included 18 classes composed of 3 canopy densities and 8 structural...
The Mount Fubilan Intrusion is part of a geologically young hypabyssal stock in the Star Mountains of Papua New Guinea. This stock was mapped as the Ok Tedi Intrusive Complex and divided into four separate bodies: the Mount Fubilan, Sydney Intrusion, Kalgoorlie, and Ningi Intrusions. Hydrothermal fluids caused alteration of...
This study examined the logbook record of the Oregon trawl fishery using a geographic information system (GIS) to determine the spatial and temporal distribution of English sole, Pleuronectes vetulus. The original logbook data for the years 1981,1982,1994,1995,1996 were filtered twice to provide both a general description of trends in the...
A model for the spatial and temporal evolution of the gray sericitic (GS) and sericite with remnant biotite (SBr) hydrothermal alteration selvages within the Butte Quartz Monzonite (BQM) of the porphyry copper deposit at Butte, Montana, is presented. The model provides a mathematical description for the location and advance of...
Typical porphyry-type Cu-Mo mineralization predates and underlies the well-known
Main Stage polymetallic veins of the Butte district, Montana. This thesis presents the
first systematic study of the isotopic characteristics of the pre-Main Stage K-silicate and
sericitic wallrock alteration related to the porphyry Cu-Mo stage.
Oxygen and hydrogen isotopic compositions were...
This study traces the development history of the city of Corvallis, Oregon. Historic
reconstruction methods and GIS analysis are used to define and describe spatial aspects of the
city's expansion through time.
Pre-settlement and early settlement landscape conditions are considered. The city's
history is divided into three time periods, 1845-1900,...
Bankfull discharge is an important indicator of streamfiow and affects
physical instream habitat. Geographic Information Systems (G IS), hydrologic
modeling, and statistical analysis were utilized to assess the relationship of
bankfull discharge recurrence intervals and land use / land cover watershed
wide and for stream adjacent buffers and bands of...