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The Great Salt Lake (GSL) of Utah, USA, is the largest saline lake in North America, and its brines are some of the most concentrated anywhere in the world. The lake occupies a closed basin system whose chemistry reflects solute inputs from the weathering of a diverse suite of rocks in its drainage basin. GSL is the remnant of a much larger lacustrine body, Lake Bonneville, and it has a long history of carbonate deposition. Inflow to the lake is from three major rivers that drain mountain ranges to the east and empty into the southern arm of the lake, from precipitation directly on the lake, and from minor groundwater inflow. Outflow is by evaporation. The greatest solute inputs are from calcium bicarbonate river...
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This report provides detailed (1:63,360-scale) mapping of the Tanana A-1 and A-2 quadrangles (500 square miles; equivalent to eight 7.5-minute quadrangles). The area is part of the Manley Hot Springs-Tofty mining districts and adjacent to the Rampart mining district to the south of the Tanana B-1 Quadrangle. This report includes detailed bedrock, surficial, structural, and stratigraphic data. Based on the resulting geologic maps, field investigations, and laboratory materials analyses, the report also includes derivative maps of geologic construction materials and geologic hazards. The Tanana A-1 and A-2 Quadrangles and surrounding area comprise several isolated mountainous ridges in the western Yukon-Tanana Upland...
Tags: 40Ar/39Ar, Aerial Photography, Aeromagnetic Map, Aeromagnetic Survey, Age Dates, All tags...
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Pollen morphology and pollen morphology in conjunction with other characteristics have elucidated the origin and evolution of various plant groups. Many studies of fossil pollen rarely discuss the effects of diagenesis and sample preparation on pollen characteristics. This paper examines the relationship of diagenesis, sample preparation (e.g., acetolysis), and staining techniques on the preservation and interpretation of pollen characteristics viewed with light, scanning and transmission electron microscopy. Based on empirical studies, different species under similar experimental conditions have different reflectance values, indicating the individual species respond differently to diagenetic events. The quantitative...
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Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Sagavanirktok B-1 Quadrangle (640 square km�equivalent to four 7.5 minute quadrangles). This mapping project reinterprets micropaleontologic correlations for 17 Sagavanirktok Quadrangle wells, and reprocesses data from the one publicly-available seismic line. Surface geologic mapping, subsurface-to-surface stratigraphic age control, and seismic framework are required to reliably decipher the complex geology of this key area of the Brooks Range. Outcrops within the Sagavanirktok B-1 Quadrangle are the closest surface expressions of Prudhoe Bay source and reservoir rocks. This study yields critical petroleum-related...
The illite layer content of mixed-layer illite/smectite (I/S) in a 2.5 m thick, zoned, metabentonite bed from Montana decreases regularly from the edges to the center of the bed. Traditional X-ray diffraction (XRD) pattern modeling using Markovian statistics indicated that this zonation results from a mixing in different proportions of smectite-rich R0 I/S and illite-rich R1 I/S, with each phase having a relatively constant illite layer content. However, a new method for modeling XRD patterns of I/S indicates that R0 and R1 I/S in these samples are not separate phases (in the mineralogical sense of the word), but that the samples are composed of illite crystals that have continuous distributions of crystal thicknesses,...
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This study contains TOC and programmed pyrolysis data, as well as vitrinite reflectance collected from 12 samples taken from the Babouri-Figuil Sedimentary basin in northern Cameroon.
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The State of Alaska Division of Geological & Geophysical Surveys (DGGS) and Division of Oil & Gas (DOG) are currently engaged in a multi-year study of the hydrocarbon potential of the Tertiary and Mesozoic strata in Cook Inlet basin. Modal analyses and routine core analyses were performed on Tertiary and Mesozoic siltstones and sandstones collected during the 2007-2010 field seasons from six geographic areas in upper and lower Cook Inlet. The reservoir quality of Cook Inlet sandstones varies widely depending on their mineralogy, geologic age, burial depth, and depositional environment. Tuxedni and Naknek sandstones have poor reservoir quality and are likely to be of equally poor quality down dip. West Foreland sandstones...
Tags: Aleutian Arc, Beluga Basin, Bluff Point, Capps Glacier, Chert, All tags...
X-Ray powder diffraction and thin section analyses indicate that marginal lacustrine mudstones of the Green River Formation in the south-central Uinta basin, Utah, contain abundant analcime. The analcime has a low Si/A1 ratio (<2.31) and occurs as very fine grained disseminated crystals and, to a lesser extent, as coarser-grained pore-filling cement. Analcime-rich mudstones and associated sandstones, siltstones, and carbonates lack volcanic detritus and zeolites other than analcime, thus making it diflicult to support the concept that the analcime formed from precursor zeolites derived from volcanic glass altered in saline, alkaline-lake water. Abundant dolomite, syneresis cracks, and the absence of freshwater pelecypods...
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Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Sagavanirktok B-1 Quadrangle (640 square km�equivalent to four 7.5 minute quadrangles). This geologic map was produced by merging a bedrock geologic map and a surficial geologic map of the Eagle A-2 Quadrangle. This mapping project reinterprets micropaleontologic correlations for 17 Sagavanirktok Quadrangle wells, and reprocesses data from the one publicly-available seismic line. Surface geologic mapping, subsurface-to-surface stratigraphic age control, and seismic framework are required to reliably decipher the complex geology of this key area of the Brooks Range. Outcrops within the Sagavanirktok B-1...


    map background search result map search result map Geologic map of the Tanana A-1 and A-2 quadrangles, central Alaska Petrology and reservoir potential of Tertiary and Mesozoic sandstones, Cook Inlet, Alaska: A preliminary analysis of outcrop samples collected during 2007-2010 field seasons Geological map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Interpretive bedrock-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Reflectance and spectral fluorescence data from the effect of diagenesis on the preservation of morphology and ultrastructural features of pollen Data from Cretaceous formations of the Babouri-Figuil Sedimentary Basin, northern Cameroon Data from Cretaceous formations of the Babouri-Figuil Sedimentary Basin, northern Cameroon Geological map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Interpretive bedrock-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Geologic map of the Tanana A-1 and A-2 quadrangles, central Alaska Petrology and reservoir potential of Tertiary and Mesozoic sandstones, Cook Inlet, Alaska: A preliminary analysis of outcrop samples collected during 2007-2010 field seasons Reflectance and spectral fluorescence data from the effect of diagenesis on the preservation of morphology and ultrastructural features of pollen