Conference Papers

The availability of space-age materials and implementation of state-of-the-art electronics is making possible the recent developments of hydrologic instrumentation. Material developments include: Synthetic-fiber sounding and tag lines; fiberglass wading rod; polymer (plastic) sheaves, pulleys and sampler components; and polymer (plastic) bucket wheels for current meters. These materials are very c

The El Nino conditions of 1982 and 1983 produced unusually frequent and intense storms along the central California coast. These storms produced much greater than normal beach erosion in Monterey Bay, causing extensive damage to coastal structures, erosion of coastal cliffs, and loss of sand from coastal dunes. The beaches accreted during the summer of 1983 and eroded again the next winter. Every

This paper describes the approach used in designing a regional network to monitor the complex ground-water-quality conditions in the San Joaquin Valley, California. The actual network approximates the ideal network with the constraint of primarily using wells that are already being monitored by someone for some purpose. Further inventories of monitoring networks and installation of some specialize

In 1979 the U.S. Fish and Wildlife Service continued its program of mark and recapture. From 31 March to 4 May field crews working at Point Barrow, Alaska, captured and marked a total of 15 polar bears (Table I). The small number was due to very poor ice conditions off the coast of Alaska, making tracking and capturing difficult. Four of the bears were recaptures from previous years. In addition,

Tissue from a calcite concretion (coal ball) and attached coal of semianthracite rank from the Belgium Bouxharmont coal bed were analyzed separately by elemental chemical, **1**3C nuclear magnetic resonance, reflectance, and paleobotanical techniques to compare relative degrees of coalification. The results indicate that static load pressure has no perceptible effect on coalification up to and inc

Field measurements of suspended sediment-transport were made across a dissipative surf zone during a storm. A correlation between high suspended mass in the water column and periods of onshore flow caused a net onshore transport of suspended sediment even though the mean near-bottom flow was directed offshore. The observed onshore migration of a nearshore bar was predicted by gradients in the cros

Because modern geochemical laboratories can seldom have all new analytical equipment, it is clear that priorities must be assigned and choices made when selecting each new instrument. X-ray fluorescence (XRF) spectroscopy has come to play a vital role in this environment largely because it is a dependable, multielement, rapid method that covers a wide range of elemental concentrations, commonly wi

Runoff, sediment transport, and precipitation were measured in three gaged basins composing two-thirds of the 20-acre site, and in a 3. 5-acre basin located 0. 3 mile south of the site. Locations and dimensions of surface collapses at the site were recorded by the site contractor. Volumes of collapsed material were calculated and converted to an equivalent weight of earth material by applying a me

Schlumberger soundings were made in the Newberry volcano area of Oregon to categorize the electrical properties of possible Cascade geothermal systems. An east-west geoelectric cross section constructed from the interpreted soundings shows a low-resistivity zone in the caldera, that corresponds to the increase in thermal gradient observed in a U. S. Geological Survey test well. Another low resisti

A 16 station array was operated over the 200 km**2 central portion of Sao Miguel utilizing 8 permanent Instituto Nacional de Meterologia e Geofisica stations and 8 USGS portable stations. Forty four local events with well constrained solutions and 15 regional events were located. In addition, hundreds of unlocatable seismic events were recorded. The most interesting seismic activity occurred in a

Designing structures to withstand earthquakes requires an accurate estimation of the expected ground motion. While engineers use the peak ground acceleration (PGA) to model the strong ground motion, seismologists use physical characteristics of the source and the rupture mechanism, such as fault length, stress drop, shear wave velocity, seismic moment, distance, and attenuation. This study present

A one-dimensional unsteady flow model has been applied to the tidal Potomac River, including its major tributaries and marginal embayments, between Washington, D. C. and Indian Head, Md. The computer model has been calibrated to simulate the combined effects of tide, freshwater inflows, and wind conditions governing flow in the system of channels. The comprehensive flow data provided by the model