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Five samples were made available as standards for the 1984 Fission Track Workshop held in the summer of 1984 (Rensselaer Polytechnic Institute, Troy, New York). Two zircons, two apatites and a sphene were distributed prior to the meeting to 40 different laboratories. To date, 24 different analysts have reported results....

Although the United States is the world's largest producer and exporter of phosphates, serious doubts have arisen in recent years that U. S. deposits could sustain this important role. The development of borehole mining; i. e. , extracting the phosphate matrix as a slurry through a drill hole, however, is...

The water level response to a slug or bailer test in a well completed in a confined aquifer has been evaluated taking into account well-bore storage and inertial effects of the water column in the well. The response range, from overdamped with negligible inertial effects to damped oscillation, was covered...

A groundwater management model is used to design an aquifer restoration system that removes a contaminant plume from a hypothetical aquifer in four years. The design model utilizes groundwater flow simulation and mathematical optimization. Optimal pumping and injection strategies achieve rapid restoration for a minimum total pumping cost. Rapid restoration...

We began continuous monitoring of H2 concentration in soil along the San Andreas and Calaveras faults in central California in December 1980, using small H2/O2 fuel-cell sensors. Ten monitoring stations deployed to date have shown that anomalous H2 emissions take place occasionally in addition to diurnal changes. Among the ten...

A viable rheological model should consist of both a time-independent part and a time-dependent part. A generalized viscoplastic fluid model that has both parts as well as two major rheological properties (i. e. , the normal stress effect and soil yield criteria) is shown to be sufficiently accurate, yet practical,...

This report describes results of some preliminary analyses of Landsat-4 Thematic Mapper data for the NASA Landsat Image Quality Analysis program. The work is being done under interagency agreement S-12407-C between the U. S. Geological Survey and NASA-Goddard Space Flight Center. Landsat-4 TM scenes for Washington, D. C. Macon, Georgia...

This preliminary report examines those radiometric characteristics of the Landsat 4 Thematic Mapper (TM) that can be established without absolute calibration of spectral data. Analysis is based largely on radiometrically raw (B type) data of three daytime and two nighttime scenes; in most scenes, a set of 512 lines were...

Many phenomena and processes in the earth sciences are a result of the electrochemical properties of rocks and minerals. Examples include formation of mineral deposits and petroleum reservoirs control of drilling muds, and success or failure of toxic waste isolation barriers. Such phenomena can be observed at a distance using...

Landsat-4 Thematic Mapper (TM) data recorded over an arid terrain were analyzed to determine the applicability of using of TM data for identifying and mapping hydrothermally altered, potentially mineralized rocks. Clays, micas, and other minerals bearing the OH anion in specific crystal lattice positions have absorption bands in the 2.2-??m...

The largest gas fields in the Rocky Mountain region occur in abnormally pressured reservoirs. These gas accumulations are different from more conventional gas accumulations in that they are commonly located in basin-center positions, they occur downdip from water-bearing rocks, and they are in overpressured or underpressured low-permeability reservoirs. We suggest...

A comparison of the aquifer parameter values obtained through the analysis of a local and a regional aquifer test involving the same area in southeast Georgia is made in order to evaluate the validity of extrapolating local aquifer-test results for use in large-scale flow simulations. Time-drawdown and time-recovery data were...

The M//L approximately equals 6. 5 earthquake that occurred near Coalinga, California, on May 2, 1983 induced changes in near-surface fault slip along the San Andreas fault. Coseismic steps were observed by creepmeters along a 200-km section of the San Andreas. some of the larger aftershocks induced additional steps, both...

An arrival time difference method utilizing refracted arrivals from earthquakes in a homogeneous, layered earth model has been developed for the simultaneous determination of near-source (in situ) velocity and relative locations of earthquakes. The method is particularly applicable when analyzing data from arrays in which most of the recording stations...

Instrumental-neutron-activation analyses are reported for two uncontaminated rocks, a phlogopite-rich clot, and two contaminated rocks from the Coyote Peak diatreme, northwestern California. These data, combined with Nd, Sr, and Pb isotopic evidence, have been modeled to a multi-stage evolution for the...

Incidental catches of 12,243 Common Murres (Uria aalge), 875 Atlantic Puffins (Fratercula arctica), 36 Black Guillemots (Cepphus grylle), and 9 Razorbills (Alca torda) were recorded off Newfoundland during the summers of 1980-1982 (26,445 net-days of fishing effort). Most catch occurred in stationary gill nets set on the sea floor at...

Chelate-extractable iron and manganese concentrations in soils over and around the Bell Creek oil field suggest that compared to low average background values, there are moderate amounts of these elements directly over the production area and higher concentrations distributed in an...

Errors in complex conceptual precipitation-runoff models may be analyzed by placing them into a statistical framework. This amounts to treating the errors as random variables and defining the probabilistic structure of the errors. By using such a framework, a large array of techniques, many of which have been presented in...

Recruitment of a mallard (Anas platyrhynchos) population was assessed on a 10,041-km2 study area in central North Dakota during 1977-80. We equipped 338 hens with radio transmitters and monitored them during the breeding season. Two hundred thirty-five of these hens furnished data reported here. Habitat use, nest site selection, fate...

Mapping of lithofacies and porosities of stratigraphic units is complicated because these properties vary in three dimensions. The method of moments was proposed by Krumbein and Libby (1957) as a technique to aid in resolving this problem. Moments are easily computed from wireline logs and are simple statistics which summarize...

Digital image transformation and rectification can be described in three categories: (1) digital rectification of spacecraft pictures on workable stereoplotters; (2) digital correction of radar image geometry; and (3) digital reconstruction of shaded relief maps and perspective views including stereograms. Digital rectification can make high-oblique pictures workable on stereoplotters that...

The gases evolved from geothermal fields, after condensation of H2O, CO2, H2S and NH3 in caustic solution, contain He, H2, Ar, O2, N2, CH4 and higher hydrocarbons. The analysis for the major components in these residual gas mixtures can be achieved by use of two simple gas chromatographs in parallel,...

The US Geological Survey (USGS) collects hydrologic data from 1332 stream, lake, and ground-water sites in Oklahoma. Information on the quantity of water from a network of 123 streamflow stations, 30 lakes, 42 peak-flow stations, three low-flow stations, and on the quality of water from 40 stream locations is published...

The discharge of effluents containing creosote and pentachlorophenol into two unlined surface impoundments at a wood-treatment facility in Pensacola, Florida, resulted in contamination of the underlying sand and gravel aquifer. These wastes contained significant amounts of chlorinated dioxins, such as isomers of hexa- and heptachlorodibenzo-p-dioxins and octachlorodibenzo-p-dioxin, probably derived from...

Pyrolusite (MnO2), hausmanite (Mn3O4), and bixbyite (Mn2O3), are important ore minerals of manganese and accurate values for their thermodynamic properties are desirable to understand better the {p(O2), T} conditions of their formation. To provide accurate values for the entropies of these important manganese minerals, we have measured their heat capacities...