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Showing 1 to 20 of 33 for “"paleocurrent"”.
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Paleocurrent Analysis of the Cretaceous Mitchell Formation, North-Central Oregon
… objective of this research was to expand the paleocurrent analysis using both macro- and micro-fabric to provide additional evidence of sediment transport direction. This information allows a better prediction of the extent, thickness, and petroleum potential of the marine Cretaceous …
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Using Cross-sets for Paleodischarge Estimation and Paleocurrent Vectors in the Parthenon Sandstone, Northwest Arkansas
… (paleodischarge and give magnitudes for paleocurrent directions) of the ancient river system which deposited the Parthenon Sandstone in northwest Arkansas. Set thickness is the vertical thickness of a group of strata conformable series (Mckee and Weir, 1953); set thickness represents …
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Influence of the West Virginia Dome on paleocurrent patterns in the Upper Devonian-Lower Mississippian Price Formation in the Central Appalachians
… in the Central Appalachians of West Virginia. Paleocurrent data collected from the Price Formation demonstrates the significance of the dome on paleoflow patterns. Exposures in West Virginia are located along the Allegheny Front and include the lowermost marine Oswayo Member, Riddlesburg Shale …
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Sedimentology of the Bullion Creek and Sentinel Butte formations (Paleocene) in a part of southern McKenzie County, North Dakota
… were measured and described. In addition, paleocurrent data were gathered from primary sedimentary structures, positions of paleochannel outcrops were noted, and samples were collected. Laboratory work consisted of thin-section petrography, scanning electron microscopy, and X-ray …
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Paleogeography of Western North America: Insights from Detrital Zircon U-Pb Geochronology and Hf Isotope Geochemistry
… zircons, as well as, geologic mapping and paleocurrent analysis. The Neoproterozoic through Pennsylvanian Yukon-Tanana terrane (YTTs) in the Coast Mountains of southeastern Alaska, the Cretaceous through Eocene strata in the San Juan basin of northwestern New Mexico and southwestern …
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Depositional history of the Black Mountain conglomerate, Mohave County, Arizona: Sedimentary response to Miocene extension
… in bedding orientation, clast compositions, paleocurrent directions, and provenance. (Abstract shortened by UMI.).
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Storm-dominated Lower Cambrian depositional environments in the Ravenswood area, Lander County, Nevada
… in a wave-dominated or storm-dominated system. Paleocurrent indicators suggest that strong westerly (present orientation of continent) winds created landward-directed currents transporting carbonate debris from the shelf to nearshore environments. Subsequently, storm-surge-ebb flows transported …
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The Muddy Creek Formation: Depositional environment, provenance, and tectonic significance in the western Lake Mead area, Nevada and Arizona
… basalt, rhyolite, quartz monzonite, and granite. Paleocurrent data for the basal River Mountain conglomerate suggest that the transport direction was to the southeast, parallel to the regional strike of high-angle normal faults. The River Mountain conglomerate may have been transported along the …
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Heterogeneity, paleohydrology, and 3D facies architecture of ancient point bars, Ferron Sandstone, Notom Delta, South-central Utah
… and paleohydraulic reconstructions. Paleocurrent measurements are consistent within one depositional unit (such as a unit bar or channel belt) and can be used to infer channel flow and bar migration patterns. Four hundred and eight paleocurrent directions were integrated with …
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Stratigraphic evolution and architectural analysis of structurally confined submarine fans: a tripartite outcrop-based study
… California. In Chapter 2, geologic mapping, paleocurrent measurements, architectural analysis, and correlation of stratigraphic columns document that the ponded Guaso I turbidite system was fed by westward- and northwestward-oriented channels currently exposed in the Southeast (Updip) Field …
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Cenozoic Sedimentary Evolution of the Helmville Basin, West-Central Montana
… grains and conglomerate clasts, and measured paleocurrent directional indicators . The western edge of the study area consists mainly of massive undifferentiated andesite and basalt that is Eocene in age. Oligocene sedimentary strata belong to the Cabbage Patch beds of the Renova Formation, …
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Cenozoic Sedimentary Evolution of the Helmville Basin, West-Central Montana
… grains and conglomerate clasts, and measured paleocurrent directional indicators . The western edge of the study area consists mainly of massive undifferentiated andesite and basalt that is Eocene in age. Oligocene sedimentary strata belong to the Cabbage Patch beds of the Renova Formation, …
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Provenance and depositional environments of the upper Permian-lowermost Triassic fluvial and lacustrine sandstones, Wutonggou low-order cycle, Bogda Mountains, NW China
… and lithics and conglomerate compositions and paleocurrent directions are documented. These data indicate that rocks of the eastern North Tianshan Suture (ENTS) and rift shoulders were the provenance lithology. Moreover, the upsection changes of petrofacies and conglomerate compositions suggest …
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Stratigraphic Architecture and Paleogeography of the Juniata Formation, Central Appalachians
… inner shelf to the upper shoreface. Isopach and paleocurrent data suggest the shoreline was oriented NE–SW and detrital sediment was dispersed west and southwest across the basin. Tectonics controlled the 2nd-Order basin-fill pattern, and these patterns vary along the strike of the basin. …
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Do Muds Sort? Experimental Test of a Hypothesis Key to Understanding Marine Bottom Currents
… within a deposit can be used as a proxy for paleocurrent velocity. Slow deposition rates on contourites (2−10 cm/kyr) make it difficult to test this hypothesis in the field and few laboratory studies have been conducted. To test the 'sortable silt' hypothesis in the laboratory, a …
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Detrital Zircon Analysis of Permian Victoria Group Sandstones, Transantarctic Mountains, Antarctica
… in mid Permian time. Sedimentary petrology and paleocurrent data indicate that this basin had two major detrital sources, a cratonic source and a volcaniclastic source that characterizes the upper Buckley Formation and younger Triassic beds. In order to investigate the sedimentary provenance …
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Distribution and origin of elongate sandstone concretions, Bullion Creek and slope formations (Paleocene), Adams County, North Dakota
… a strongly east-west orientation. Averages of paleocurrent measurements of the associated sand and sandstone are also easterly.</p> <p>The elongate concretions occur slightly above and below the Rhame bed (a white marker zone at the top of the Slope Formation), in sand units at the base of the …
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The stratigraphy and sedimentology of the Sentinel Butte Formation (Paleocene) in south-central Williams County, North Dakota
… thicker than previously estimated. </p><p> Paleocurrent data from this area indicate a SSW flow direction. This information, combined with data from earlier studies, suggests that the source area for these sediments was not the Powder River Basin. Examination of the thicknesses of various …
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Sedimentology of the Catalina Dome and taxonomy of Mistaken Point small fronds
… Turbidite ripple marks show a change in paleocurrent direction from eastward to southward in the Trepassey Formation, consistent with a change from convergent to strike-slip tectonics that occurred diachronously across the basin. Volcanic ash beds are more common in the Catalina Dome …
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Paleoenvironmental and tectonic reconstruction of the lower Eocene Ghazij Formation and related units, Balochistan, Pakistan: Implication for India -Asia collision
… of sandstone and shale dominate in the east, (3) paleocurrent directions indicate southeastward flowing sediment dispersal paths during late Paleocene-early Eocene time, opposite that found in the late Cretaceous, suggesting a reversal in the depositional slope of the Cretaceous shelf, (4) the …
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