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The Mississippian sequence exposed at North Georgetown Canyon, Idaho is newly recognised as a facies belt, which adds to knowledge of Mississippian stratigraphy and petroleum geology in the Overthrust belt of Idaho, Wyoming, and Utah. In the newly recognized facies belt in the Aspen Range, the Madison Group is represented...

Forty oil samples from across the North Slope of Alaska have been analyzed by the U.S. Bureau of Mines and the U.S. Geological Survey. Results of these analyses suggest two separate genetic oil types. The first, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and...

Fragments of silicified rocks that are associated with deposits of base and precious metals may be transported as cobbles and pebbles in alluvium far downstream from the source outcrop. These rocks commonly exhibit certain characteristics which distinguish them from other detrital siliceous material, and may thus serve as a useful...

No abstract available....

Hydrogeologic studies prove that natural dissolution of bedded salt occurs at shallow depths in many parts of the Permian Basin of the southwestern U.S.A. This is especially well-documented on the east side of the basin in study areas on the Cimarron River and Elm Fork in western Oklahoma, and on...

Deformation along the Denali fault in the Delta River canyon was determined from geodetic surveys in 1941/1942, 1970, 1975, and 1979. The data were best for the 1975–1979 interval; in that period the average strain accumulation was essentially pure right lateral shear at a rate of 0.6 ± 0.1 μrad/a...

A positive magnetic anomaly extends discontinuously from the south side of the Copper River basin, along the southeast side of Cook Inlet and Shelikof Strait, and southwestward from Kodiak Island to near Sutwik Island. Regionally, this anomaly parallels the Border Ranges fault and...

Sky and solar radiance are of major importance in determining the ground temperature. Knowledge of their behavior is a fundamental part of surface temperature models. These two fluxes vary with elevation and this variation produces temperature changes. Therefore, when using thermal-property differences to discriminate geologic materials,...

The chemical composition and stratigraphy of the Black River Group in southwestern Ohio were studied. Chemical analyses were done on two cores of the Black River from Adams and Brown Counties, Ohio. These studies show that substantial reserves of high-carbonate rock are present in the Black River at depths of...

The basin fill beneath the Sevier Desert of western Utah contains evaporites that were deposited in a broad closed basin. All of the basin fill penetrated by the Gulf Oil 1 Gronning contains abundant volcanic detritus and its alteration products of Cenozoic age. Fission-track dating of tuffaceous sandstone yields ages...

A preliminary test of biogeochemical exploration for locating uranium occurrences in the Marfa Basin, Texas, was conducted in 1978. Only 6 of 74 plant samples (mostly catclaw mimosa, Mimosa biuncifera) contained uranium in amounts above the detection limit (0.4 ppm in the ash) of the conventional fluorometric method. The samples were...

Low levels of selenium (0.1-500 ppm) in both organic and inorganic geologic materials can be semiquantitatively measured by isolating Se as a thin film for presentation to an energy-dispersive X-ray fluorescence spectrometer. Suitably pulverized samples are first digested by fusing with a mixture of Na2CO3 and Na2O2. The fusion cake...

Rates of sedimentation calculated from analyses of 210Pb activities in cores from two shallow lakes whose mean depths are 2.4m, Upper Klamath Lake and Lake Euwana (Klamath County, Oregon), indicate that they are filling at approximately 3.0mm/yr. Average sedimentation rates for compaction-corrected cores range from 0.9mm/yr to 8.5mm/yr or from...

The fractionation of 13C between calcite and graphite, Δ(Cc-Gr). is consistently small (2.6–4.8 permil) in 34 assemblages from upper amphibolite- and granulite-facies marbles of the Grenville Province. In 25 samples from the Adirondack Mountains, New York, it decreases regularly with increasing metamorphic temperature. The fractionations are independent of absolute δ13C values...

Measurements have been made of the oxygen isotope and chemical composition of glass and phenocrysts in lavas and coexisting minerals in mantle nodules. Temperatures of formation of these assemblages have been estimated from various chemical thermometers and range from 855?? to 1,300?? C. The permil fractionations between coexisting orthopyroxene and...

Cretaceous silicoflagellate assemblages from Arctic Ocean USGS Core 437 show Vallacerta siderea the most abundant species; most species of Lyramula disappear halfway up the core; only L. burchardae, n. sp., persists into the upper sections. These occurrences are untypical of the few documented Cretaceous assemblages from other areas. A Campanian...

The glass transition has been experimentally detected in basalt as (1) an increase in the aggregate linear thermal expansion coefficient αL, (2) an abrupt change in the temperature dependence of Young's modulus dE/dT, and (3) a change in stress relaxation behavior that effectively separates the T> TG and T < TG creep regimes. Transition temperatures determined by the...

A network of seismograph stations has operated in north-central New Mexico since 1975. The network is approximately 200 by 300 km in size and encompasses the Rio Grande rift there. Several seismic refraction experiments have been reported in the literature for the region of the network and adjacent areas. Because...

A discussion of the means employed by the US Geological Survey to facilitate map usage, covering aspects of project Map Accessibility Program including special rolled and folded map packaging, new market testing, parks and campgrounds program, expanded map dealer program, new booklet-type State sales index and catalog and new USGS...

Vitrinite reflectance measured in immersion oil (Ro) on kerogen extracted from hydrothermally altered mudstones in borehole M-84 at the Cerro Prieto geothermal field exhibit an increase in mean reflectance (Ro">Ro) from 0.12 per cent at 0.24 km depth to 4.1 per cent at 1.7...

The Fraunhofer line discriminator (FLD), an airborne electro-optical instrument designed to measure solar-stimulated luminescence, has a sensitivity approaching that of current laboratory fluorescence spectrometers. The feasibility of using an airborne FLD for detection of near-coastal and open-ocean phytoplankton was established by using a laboratory fluorescence spectrometer to measure the luminescence...

The morphology and distribution of ridges and scarps on Mars in the ± 30° latitude belt were investigated. Two distinct types of ridges were recognized. The first is long and linear, resembling mare ridges on the Moon; it occurs mostly in plains areas. The other is composed of short, anastomosing...

Uranium ores at the Midnite mine, near Spokane, Washington, occur in phyllites and calcsilicates of the Proterozoic Togo Formation, near the margins of an anomalously uraniferous, porphyritic quartz monzonite of Late Cretaceous age. The present geometry of the ore zones is tabular, with the thickest zones above depressions in the...

A random model of fault motion in an earthquake is formulated by assuming that the slip velocity is a random function of position and time truncated at zero, so that it does not have negative values. This random function is chosen to be self-affine; that is, on change of length...

[No abstract available]...