Conference Papers

Recent geologic mapping on the Island of Hawaii is compiled in a detailed new 1:100,000-scale geologic map. The lava flows and pyroclastic deposits of each volcano are assigned to major lithostratigraphic units based on lithology and stratigraphic relations. However, the emphasis of the map is strongly chronostratigraphic. Lavas of latest Pleistocene and Holocene age, which form almost all of the

No abstract available at this time.

Alternate conceptual models to explain near-surface heat-flow observations in the central Oregon Cascade Range involve (1) an extensive mid-crustal magmatic heat source underlying both the Quaternary arc and adjacent older rocks or (2) a narrower deep heat source which is flanked by a relatively shallow conductive heat-flow anomaly caused by regional ground-water flow (the lateral-flow model). Rel

Equipment and methodology have been developed to monitor sediment resuspension at two sites in Old Tampa Bay. Velocities are measured with electromagnetic current meters and suspended solids and turbidity are monitored with optical backscatterance sensors. In late November 1989, a vertical array of instrument pairs was deployed from a permanent platform at a deep-water site, and a submersible inst

The U.S. Geological Survey has acquired a large collection of geotechnical data, drill cores, and crushed samples of oil shale from the Eocene Green River Formation in Colorado, Wyoming, and Utah. The data include about 250,000 shale-oil analyses from about 600 core holes. Most of the data is from Colorado where the thickest and highest-grade oil shales of the Green River Formation are found in th

As part of the paleohydrology study of the Yucca Mountain Project, strontium-isotope analyses of carbonate deposits, ground water, and major rock reservoirs of strontium are in progress. This paper presents a summary of the strontium-isotope data obtained through 1989. Calcium carbonate is ubiquitous in the vicinity of Yucca Mountain, where it occurs as pedogenic horizons and rhizoliths, small vei

This study was initiated to investigate the impacts of geothermal development in the Corwin Springs Known Geothermal Resources Area (KGRA) on the hydrothermal features of Yellowstone National Park. To determine possible hydrogeochemical connections, we used the diagnostic stable and radioactive isotopes of several elements, and the chemical and gas compositions of thermal and cold waters from the

Sea otters (Enhydra lutris) that were captured in western Prince William Sound (PWS) or the Gulf of Alaska, treated, and held in captivity at the temporary rehabilitation centers established in response to the T/V Exxon Valdez oil spill were instrumented with radio transmitters, released into eastern PWS, and monitored by radiotelemetry. We undertook the present study to gain information for guidi

Within the State boundaries are numerous gold deposits and anomalies scattered throughout the geological record. Many examples occur in rocks ranging in age from Archean to Tertiary, and in Quaternary to Recent unconsolidated gravels and sands. Yet relatively few of these deposits and anomalies have been explored and only a handful have been drilled. Since much of Wyoming is underlain by an Archea

Four methods were used for marking sea otters (Enhydra lutris) captured and treated during the response to the T/V Exxon Valdez oil spill. Colored and numbered flipper tags were placed on each sea otter that was brought to the otter treatment centers. These tags allowed individual recognition and permitted the tracking of individuals through the treatment and holding processes. Recovery of tagged

The study of Quaternary geology provides information to evaluate geologic conditions and identify geologic constraints on construction in the West Desert Hazardous Industry Area (WDHIA). The WDHIA includes portions of the Great Salt Lake Desert to the west, underlain by several thousand feet of sediments capped by saline mudflats, and Ripple Valley to the east, separated from the Desert by the Gra

Trench 14 was excavated to investigate the extent of Quaternary movement on the Bow Ridge fault, a north-south structure on the east side of Yucca Mountain. The trench exposes calcite and opaline silica as fault breccia cements, veinlike fault fillings, and slope-parallel calcretes. Although the latter are clearly similar to calcretes of pedogenic origin, the cementing and fault-filling mineraliza