Coral reef ecosystems are the most diverse on earth, and their subsistence is being threatened by natural and adverse anthropogenic patterns and processes. In an effort to understand and protect these marine environments, several programs have outlined strategies and initiatives. For example, the United States Coral Reef Task Force’s Mapping...
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...
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...
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...
Glacial deposits on San Francisco Mountain, Arizona, were mapped in order to provide constraints on ice extents in separate valleys for late Pleistocene glacial events. Qualitative and semi-quantitative relative dating methods were employed in order to correlate moraines between drainages and to provide a basis for distinguishing between separate glacial...
Fast ice flow and unstable ice sheet behavior were characteristic features of the Lake Michigan Lobe of the southern Laurentide Ice Sheet. Such behavior may result from some combination of subglacial-sediment deformation and decoupled sliding at the ice-bed interface. Both mechanisms depend on high water pressure relative to ice pressure....
The High Lava Plains province (HLP) of southeastern Oregon is a Miocene to Recent volcanic upland characterized by widespread basaltic volcanism and west-migrating rhyolitic volcanism. New ⁴⁰Ar/³⁹Ar ages for HLP rhyolites demonstrate that the trend of migrating rhyolitic volcanism is robust, reflecting westward migration at a rate of -35 km/m.y....
The San Vicente zinc lead deposit is located in the Eastern Andes of
Central Peru. The deposit is an epigenetic Mississippi Valley-type deposit
based on stratigraphic, geologic, petrographic, and geochemical evidence.
The dolomite host rocks of the Pucara Group are of Triassic-Jurassic
age. The source of metals are red sandstones...
Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to...
The Clarno Formation is a series of volcanic, volcaniclastic, and related intrusive rocks located in central Oregon. It is the westernmost extent of a broader Eocene magmatic belt that covers much the western United States. The magmatic belt stretches eastward from Oregon to western South Dakota, and from the Canadian...