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Modern computer technology offers cartographers the potential for transition from conventional film-oriented methods to digital techniques as the way of mapping in the future. Traditional methods utilizing silver halide aerial and lithographic films for storage are time proven, and film is a very high density archival storage media. In view...

As Cain (1979) indicated might happen in the last IUGG quadrennial report, added resources were made available during the past few years and a real impulse was added to the geomagnetic work in the US by the launching of the MAGSAT Satellite. This new effort paid off in terms of...

Phytoplankton dynamics in the upper reach of the northern San Francisco Bay estuary are usually characterized by low biomass dominated by microflagellates or freshwater diatoms in winter, and high biomass dominated by neritic diatoms in summer. During two successive years of very low river discharge (the drought of 1976-77), the...

Igneous rocks commonly have large magnetic susceptibilities so that high topographic relief in crystalline terrane can produce significant anomalies in aeromagnetic surveys. Topographic anomalies are particularly significant in relatively undeformed volcanic terrane because young volcanic rocks generally have large natural remanent magnetizations as well as large susceptibilities. These anomalies commonly...

Tectonism in SW Wyoming and adjoining areas, and fluctuations of sea level in the central USA during the mid-Cretaceous are represented by the regional stratigraphy of the Frontier Formation. The Frontier consists mainly of clastic rocks that were deposited in marine and nonmarine environments during latest Albian, Cenomanian, Turonian, and...

Methods are described for developing geochemical reaction models from the observed chemical compositions of ground water along a hydrologic flow path. The roles of thermodynamic speciation programs, mass balance calculations, and reaction-path simulations in developing and testing reaction models are contrasted. Electron transfer is included in the mass balance equations...

The Eastern Devonian shales are represented by a sequence of sediments extending from New York state, south to the northern regions of Georgia and Alabama, and west into Ohio and to the Michigan and Ilinois Basins. Correlatives are known in Texas. The shale is regionally known by a number of...

A method of preparing a detailed landslide-inventory map has been developed which provides the engineering geologist with the basic information for evaluating and reducing landslide hazards or risk on a regional or community level. For each landslide, the map depicts state of activity, certainty of identification, dominant type of slope...

Studies of stream and sediment-pore waters largely explain the genesis of concretionary Mn-Fe-oxides in Maine. Waters of two small streams near Jackman, Maine, were studied in terms of pH, Eh, dissolved oxygen, dissolved organic carbon, dissolved Mn, total dissolved Fe, and ferrous and ferric Fe. Pyrite Creek has profuse concretions...

The large (mean height 25 m, spacing 300 m), relatively straight-crested dunes of the central Oregon coast migrate an average of 3.8 m/yr toward an azimuth of 26°. The dunes are transverse to the strong, south-southwesterly winter storm winds that are responsible for...

Most workers agree that Proterozoic anorthosite massifs represent the crystallization products of mantle-derived magmas1,2, although the composition of the parental melts is a major unsolved petrological problem 3. As mantle-derived rocks, the massifs can be used as geochemical probes of their late Precambrian upper mantle sources. We report here Nd...

The U.S. Geological Survey and Petroleum Information Corporation in Denver, Colorado, developed the Eastern Gas Shale Project (EGSP)Data System for the U.S. Department of Energy, Morgantown, West Virginia. Geological, geochemical, geophysical, and engineering data from Devonian shale samples from more than 5800 wells and outcrops in the Appalachian basin were...

The Nd and Sr isotopic ratios on a suite of continental alkali basalts from Marie Byrd Land, West Antarctica, define a change in the source over the range of K/Ar dates between 1 and 28 m.y. ago. The 87Sr/86Sr isotopic ratios (0.7026 to 0.7031) are unusually low for continental alkali...

A regression equation used to estimate a variable is appropriately used only to estimate the dependent variable of that equation; the equation is inappropriately used when solved for an independent variable. Examples given here of this misuse of regression equations are based on...

No abstract available....

Cloacal swabs collected from wild bald eagle nestlings (Haliaeetus leucocephalus) were tested for viruses. A virus isolated from one of these samples had a lipid coat and contained DNA. Electron microscopy confirmed that it was a herpesvirus. This appears to be the first report of a herpesvirus isolation from a...

Several species of nymphs from the family Hypoderidae have been reported from pelecaniform birds (Cerny, 1969, Folia Parasit. (Praha) 16:271-274; Pence, 1972, J. Med. Ent. 9: 435-438; Pence and Courtney, 1973, J. Parasitol. 59: 711-718); however, there are no records from the white pelican, Pelecanus erythrorhynchos. I report here the...

No abstract available....

176Hf/177Hf ratios are presented for oceanic volcanics representing both extremes of the range of mantle HfNdSr isotopic variation. Hf from critical mid-ocean ridgebasalts shows that 176Hf/177Hf does indeed have a greater variability than 143Nd/144Nd and 87Sr/86Sr in the depleted mantle. This extra variation is essentially of a random nature, and...

Data acquired by Landsats 1, 2, and 3, are beginning to provide the information on which an improved mineral and energy resource exploration strategy can be based. Landsat 4 is expected to augment this capability with its higher resolution (30 m) and additional spectral bands in the Thematic Mapper (TM)...

This article establishes approximate empirical relations for determining the minimum unit stream power, bed shear stress and mean flow velocity capable of moving cobbles and boulders on streambeds. The derived equations then are used to estimate the minimum paleoflows that could have transported the boulders of two ancient...

The U. S. Geological Survey, in cooperation with the U. S. Bureau of Mines and the Office of Surface Mining Reclamation and Enforcement, is investigating effects of mining on flood frequency and magnitude within the basin. Changing land use, particularly the acceleration of surface mining, may cause or contribute to...

The Wasatch Mountains in northern Utah are a north-south trending range with steep slopes caused by faulting less than 10,000 years ago. Through the natural processes of rain, frost-wedging, gravity, and earthquakes these slopes are slowly being eroded. A geologic history of instability is recorded at the base of the...

No abstract available....