Publications

Present Mount Shasta, California, area hydrologic characteristics were documented to compare future changes due to land use or volcanic activity. Lower flanks of Mount Shasta consist of broad aprons of pyroclastic-flow, debris flow, and fluvial deposits, with incised channels on upper parts of the mountain. Data include glacial areas and volumes, streamflow, sediment concentrations, temperature, a

No abstract available.

No abstract available.

The climactic eruption of Mount Mazama has long been recognized as a classic example of rapid eruption of a substantial fraction of a zoned magma body. Increased knowledge of eruptive history and new chemical analyses of ∼350 wholerock and glass samples of the climactic ejecta, preclimactic rhyodacite flows and their inclusions, postcaldera lavas, and lavas of nearby monogenetic vents are used her

Study of active volcanoes yields information of much broader significance than to only the discipline of volcanology. Some applications are 1) interpretation of lava-flow structures, stratigraphic complexities, and petrologic relations in older volcanic units; 2) interpretation of bulk properties of the mantle and constraints on partial melting and deep magma transport; 3) interpretation of geophy

The 1987 International Symposium on Erosion and Sedimentation in the Pacific Rim, held August 3–7, 1987, in Corvallis, Oreg., included a special session on the geomorphic and hydrologic dynamics of zero-order drainage basins. “Zero-order basin” is one of several terms used to describe unchanneled swales or hollows that may occupy considerable areas of higher-order drainage basins. These basins ser

The 75th anniversary of the founding of the U.S. Geological Survey (USGS) Hawaiian Volcano Observatory (HVO) was celebrated during January 1987. The festivities began on January 9 with the opening in Hilo of a major exhibit at the Wailoa Center on the current work of HVO, its history, and its special relationship to Hawaii Volcanoes National Park. In addition to spectacular photographs of volcanic

No abstract available.

Eocene siliceous and calcareous phytoplankton, with emphasis on silicoflagellates, were studied in 62 samples from DSDP Sites 612 and 613 on the continental slope and rise off New Jersey. The mid-latitude assemblages correlate well with assemblages from California, Peru, and offshore of southern Brazil, but are distinctly different from high-latitude cold-water assemblages of the Falkland Plateau

Quaternary silicoflagellates from Deep Sea Drilling Project (DSDP) Mid-Atlantic Leg 94 are generally sparse and dissolution-thinned. Mesocena quadrangula, a low-latitude biostratigraphic guide species, occurs at all four sites studied (606, 607, 609, and 611), allowing identification of low-latitude zones—Dictyocha aculeata Zone, Mesocena quadrangula Zone, and Dictyocha stapedia stapedia Zone. A l

To test whether a catastrophic earthquake could affect an active magma system, mean abundances (adjusted for "olivine control") of titanium, potassium, phosphorus, strontium, zirconium, and niobium of historic lavas erupted from Mauna Loa Volcano, Hawaii, after 1868 were analyzed and were found to decrease sharply relative to lavas erupted before 1868. This abrupt change in lava chemistry, accompa

Debris flows exhibit conspicuous dynamic interactions among their solid and fluid constituents. Key features of the interactions are neglected in traditional theories that treat debris flows as viscoplastic continua or as uniformly dispersed grain flows, but improved understanding of grain-grain and fluid-grain interactions has emerged from recent experimental and theoretical research. Grain-flow