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Showing 1 to 20 of 34 for “"valley fill"”.
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Hydrologic Response of Alternative Valley Fill Reclamation Designs
… Original Contour), involves the construction of valley fills of headwater systems. Recent research suggests that current MTM reclamation techniques increase stormflow response of the affected watersheds when compared to the original, undisturbed conditions. One method that has shown success in …
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Late Quaternary Mississippi River Incised Valley Fill: Transgressive Depositional Packages
… reentrenchment of the Mississippi River incised valley. Meltwater floods from proglacial lakes incised into older deposits followed by braided fluvial (substratum) aggradation due to reduced carrying capacity after floods followed by meandering fluvial(topstratum aggradation as fluvial gradients …
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Stream functional response to mountaintop removal and valley fill coal mining
Mountaintop removal and valley fill (MTRVF) mining has become a widespread means of coal extraction in the central Appalachians. During MTRVF several hundred meters of overburden are removed to access coal seams, and excess rubble is dumped into adjoining valleys and streams. Filling valleys …
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Comparison of Groundwater Seepage Modeling in Approximate Original Contour and Geomorphic Valley Fill Design
… West Virginia is generally placed in headwater valleys. Known as valley fills, these structures are designed to move water rapidly through constructed drains to maximize geotechnical stability using the conventional design method termed Approximate Original Contour (AOC). Seepage from valley …
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Small mammal communities on a reclaimed mountaintop mine/valley fill landscape in southern West Virginia
Mountaintop mine/valley fill is a large-scale form of strip mining whose effects on small mammals had not previously been examined. Small mammals were captured by Sherman trap and drift fence array (pitfall and funnel traps) on 3 treatments representing the mined landscape and intact forests …
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Using Electrical Resistivity Imaging to Relate Surface Coal Mining Valley Fill Characteristics to Effluent Stream Quality
… affecting water quality and aquatic ecology. Valley fills created from excess overburden are prominent features of many mined landscapes. Increased total dissolved solids (TDS), as measured by its surrogate specific conductance (SC), is a significant water quality concern related to the …
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Optimizing geo-cellular reservoir modeling in a braided river incised valley fill: Postle field, Texas County, Oklahoma
Includes bibliographical references (pages 123-130).
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Late quaternary valley fill sediments in the River Tyne valley: Understanding late Devensian deglaciation and early postglacial response in northern England
… and early post-glacial history of the River Tyne Valley, Northumberland. Data has been gathered through description and interpretation of sedimentary sequences and stratigraphies from quarry and cut-bank exposure, the development of a geochronology was attempted, based on optically stimulated …
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Valley Widening and the Composite Nature of Valley Margin Sequence Boundaries: Evidence from the Neilson Wash Compound Valley Fill, Cretaceous Ferron Sandstone, Utah
Incised valleys are at the center of a debate about whether sequence boundaries are chronostratigraphically significant. Current research has suggested that the sequence boundary that makes up the floor and walls of an incised valley is constantly being modified throughout the entire relative …
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High Efficiency SEPIC Converter For High Brightness Light Emitting Diodes (LEDs) System
… the middle capacitor is replaced with a valley-fill circuit. The valley-fill circuit could reduce the voltage stress of output diode and middle capacitor under the same power factor condition, thus achieving higher efficiency. Instead of using an electrolytic capacitor for the filter, a …
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Depositional Environments and Sequence Stratigraphy of Upper Mississippian Strata in the Central Appalachian Basin
… West Virginia constitute a wedge of strata that filled the Appalachian basin over a ~7 million year time interval. Seventeen transgressive-regressive sequences comprise the study interval in the basin depocenter. Five sequence types defined by the degree of incision and the thickness/ character …
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Intermontane valley fills
Sedimentary valley fills are a widespread characteristic of mountain belts around the world. They transiently store material over time spans ranging from thousands to millions of years and therefore play an important role in modulating the sediment flux from the orogen to the foreland and to …
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Electrical Resistivity Imaging of Preferenital Flow through Surface Coal Mine Valley Fills with Comparison to Other Land Forms
… parameter, specific conductance (SC). The SC of valley fill effluent is a function of fill construction methods, materials, and age; yet hydrologic studies that relate these variables to water quality are sparse due to the difficulty of implementing traditional hydrologic measurements in fill …
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Analyses of coal extraction and spoil handling techniques in mountainous areas
… operations (1) Coal Extraction, and (2) Valley fill slope stability are analyzed.;The objective of this research is to analyze the pertinent coal extraction methods, and to study the slope stability of valley fill slopes using deterministic as well as probabilistic approach.
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Recent fluvial geology in western North Dakota
… many drainage channels that are incised into valley fill are characterized by steep, unvegetated sides. Many such channels contain actively eroding scarps. The origin of these scarps is most frequently related to increased water velocity causing accelerated erosion on a steepened reach of the …
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Groundwater flow in part of the Little Missouri River Basin, North Dakota
<p> The Little Missouri valley in western North Dakota is deeply incised into slightly permeable Mesozoic and Cenozoic sediments. An evaluation of the groundwater flow in part of this valley was 'based on the present groundwater flow-system models. Abrupt changes in the hydrochemical facies have …
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Geology of the southern portion of Martin's Ridge Monitor Range, Nye County, Nevada
… homocline conical evidence suggest that Antelope Valley is a graben containing approximately 2,000 feet of valley fill. Combined geologic and geophysical evidence indicates that Martins Ridge is the west limb of a large anticlinal structure which once spanned Antelope Valley.</p>
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Raptor abundance and diversity and red-shouldered hawk ( Buteo lineatus) habitat characteristics on reclaimed mountaintop mines in southern West Virginia
… (migration, summer, and winter) on 3 mountaintop/valley fill mines in southern West Virginia. Habitat characteristics of Red-shouldered Hawks (Buteo lineatus) were examined at landscape and microhabitat scales. Forty-eight points were surveyed monthly (Feb. 2000--Jan. 2001) using broadcast calls. …
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Regional stratigraphy of the Newcastle Formation (Lower Cretaceous) in eastern Montana and western North Dakota
… environments: 1) Shallow marine deposits, 2) Valley-fill deposits. The shallow marine sediments were deposited while the Western Interior Sea was at its maximum lowstand position and exhibit a predominant coarsening-upward log character. The valley fill sediments were deposited as a result of …
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Analysis of a Middle Pennsylvanian Channel Complex in Pikeville, Kentucky
… fluvial architectural elements within an incised valley. A photo-mapping of the channel elements helped to identify major facies, and to interpret different autocyclic and allocylic factors. Backstripping revealed true dimensions of the units and magnitude of local subsidence. When the incised …
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