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Showing 1 to 20 of 35 for “"Alluvial fans"”.
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Climatic and Geomorphic Interactions on Alluvial Fans in the Atacama Desert, Chile
Alluvial fan surfaces in the Atacama Desert of northern Chile preserve evidence of recent, precipitation-driven, surface flows. Determining the hydrologic characteristics of these flows is important for understanding the effects of rare yet significant storms in the region. Flow reconstruction, …
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REMOTELY MAPPING SURFACE ROUGHNESS ON ALLUVIAL FANS: AN APPROACH FOR UNDERSTANDING DEPOSITIONAL PROCESSES
… and understand depositional processes on active, alluvial fan surfaces in Death Valley, CA. Surface roughness on the scales of grain size and topography on alluvial fan surfaces is expected to vary with depositional processes, including fluvial and mass movement events, as well as surface runoff …
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Comparison of models to mitigate flood hazard to transportation alignments on alluvial fans
… may provide better discharge estimates for alluvial fan flood mitigation studies than the one-dimensional, stochastic Federal Emergency Management Agency (FEMA) model; A modified version of the one-dimensional, stochastic FEMA model (French, 1992), and the one- and two-dimensional, …
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Pedogenesis and geomorphic implications of soils developed on Blue Ridge alluvial fans, Virginia
Alluvial fans along the western footslopes of the Blue Ridge province, Virginia range over a linear distance of at least 200 km and spread westward up to 4.8 km. Certain soils formed on the fans appear old and highly weathered. Little detailed physical, chemical, or mineralogical data is available …
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Dating of alluvial fans from NW Argentina using cosmogenic nuclides and optically stimulated luminescence technique
Alluvial fans are important geomorphic markers and sedimentary archives of tectonic and climatic changes. Hence, basins providing perfect studying conditions can often be found in arid regions due to the low weathering impact and thus well preservation of sedimentary features. Twelve samples for …
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Ravine alluvial fans as records of landscape change in the Le Sueur River Basin, southern Minnesota
Ravine alluvial fans in the Le Sueur River Basin (LSRB) of south-central Minnesota record post-glacial Holocene changes and modern anthropogenic disturbances to land cover and hydrology in high-latitude watersheds. Seventy meters of base-level drop at the end of the last glaciation initiated …
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Talus Features of the Middle Columbia River: Typological and Locational Analyses
… Pit features are also located in colluvium and alluvial fans, and at the base of cliff overhangs. Over 568 of these features have been documented for 48 sites within the project area of the Priest Rapids and Wanapum reservoirs. Pits may have been used for hunting blinds, storage (food and/or …
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The Muddy Creek Formation: Depositional environment, provenance, and tectonic significance in the western Lake Mead area, Nevada and Arizona
… of the River Mountain conglomerate forming alluvial fans that were constrained to the basin margins. When extension subsided, coarse-grained material prograded into the basin, forming the Boulder Basin conglomerate. (Abstract shortened with permission of author.).
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Soil Heterogeneity in Arid Shrublands: Biotic and Abiotic Processes
… the evolution of soil heterogeneity on arid alluvial fans. Soil formation begins when depositional or erosional processes cease and a geomorphic surface becomes stable. The transformation of sediment to soil (pedogenesis) affects a multitude of hydrologic processes operating across a range of …
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Aspectos físicos e o uso do solo na microbacia do rio da ribeira, município de Santa rita – PB.
… grooves, and gully, plus a large quantity of alluvial fans that protrude over the lowlands, often choking small streams and springs. Aside from these aspects should be highlighted the large amount of pesticides used on this crop, which infiltrate the soil, then reappear on the surface through …
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FUNZIONE DEL BOSCO NELLA FASE DI ARRESTO DEI DEBRIS FLOW
… hazards is represented by debris flows. Alluvial fans, which have been just built by debris flow events occurred in the past, in fact, are areas where human activities (homes, factories, etc.) have always been developed. People living in mountain areas, in this way, must adopt expensive …
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Landscape forcing mechanisms on Quaternary timescales: The Tabernas Basin, SE Spain
… sedimentary assemblages (river terraces and alluvial fans) often provide important records of long-term landscape evolution. The reconstruction of global terrace sequences has enabled the identification of numerous external and internal forcing mechanisms which operate within the Quaternary …
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Quantitative geomorphology and hydrology of the Cass River Basin, New Zealand
… four geomorphic areas: bedrock areas, high-angle fans, moderate-angle fans, and a low-angle fan. The bedrock areas consist of fractured greywacke; the high-angle fans are active talus cones; the moderate-angle fans are inactive fans preserved from the last glacial advance; and the low-angle fans …
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Sedimentology of the Penrith sandstone and brockrams (Permo-Triassic) of Cumbria, north-west England
… are predominantly the deposits of coalescing alluvial fans which accumulated as the products of subaerial sheetflood, transitional debris flow and braided river processes at the margins of desert basins bordering the upstanding Lake District. The fans were deposited on an irregular topography …
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Evaluating different remote sensing techniques for detection of Saharan dust and characterisation of dust sources
… dust sources are detected during 2008, 45% from alluvial fans, 15% from lake, 13% from alluvial plains, 6% from agriculture, 6% from river, 2% from multiple landforms in a single MODIS pixel and thus their nature could not be determined, while 13% were diffuse and no source could be detected. …
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The geology of the Waterberg group in the southern Portion of the Waterberg basin
… Formations are interpreted as a series of alluvial fans forming a bajada along the scarp caused by the uplifted block on the southern side of the Murchison strike-slip fault zone. The Skilpadkop and Setlaole Formations are considered to have been deposited on narrow braidplains. The …
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Groundwater and Tidal Controls on Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia
… 1995 and 1997 by removing the toe of small sandy alluvial fans and covering the underlying coarse gravel bed with a low permeability cap. The basal Quaternary gravels were deposited in a creek valley incised into a thick sand-and-clay Cretaceous delta. The alluvial-fan apron developed at the base …
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Mechanisms governing avulsions in transient landscapes : analysis of the May 2006 Suncook River avulsion in Epsom, New Hampshire
… in environments such as deltas, floodplains, and alluvial fans where net-deposition can raise the bed of the river above its floodplain. Avulsions are less frequent in transient landscapes, such as New England, where topography and hydrography are still responding to recent glaciation. One of …
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