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Showing 1 to 16 of 16 for “"Lacustrine sediment"”.
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Dating of fallout in lacustrine sediment in southwestern Utah
… The reservoir was shown to have a constant sedimentation rate and to be relatively undisturbed. A 40 centimeter (cm) core taken from this reservoir contained sediment deposited after 1974 and did not reach back to the NTS fallout years of 1951 to 1959 or back to the peak worldwide fallout …
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Lacustrine Sediment Record of Multiple Quaternary Lava Dams on the Owyhee River, Southeastern Oregon
… the Quaternary evolution of the Owyhee River. Sediment records from lava-dammed lakes were investigated to understand effects of the West Crater (WC) lava dam (~70 ka), the Saddle Butte 2 lava dam (~144 ka), and the Bogus Rim lava dam (~1.9 Ma). Evidence from the WC lava dam and related …
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Late Pleistocene-Holocene sedimentary processes at the active margin of South-Central Chile : marine and lacustrine sediment records as archives of tectonics and climate variability
… to study both processes, I examined marine and lacustrine sediments from different depositional environments on- and offshore the south-central Chilean coast (38-40°S). I combined sedimentological, geochemical and isotopical analyses to identify climatic and tectonic signals within the …
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Pleistocene stratigraphy of the Red Lake Falls area, Minnesota
… Minnesota. Five formations are largely glacial, sediment, and two are largely lacustr1ne sediment deposited during phases of Lake Agassiz. </p><p> The Gervais Formation (pre-Wisconsinan or early Wisconsinan) is mostly fluvial or lacustrine sediment modified by glacial ice of unknown source. The …
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Late Holocene earthflows of the Willard Playa/dune complex, Estancia Valley, New Mexico; a geomorphic response to climatic change
Late-middle to late Holocene dune sediment that overlies Pleistocene lacustrine sediment marks the onset of xeric conditions in the Estancia Valley, central New Mexico. Incised into the underlying lacustrine sediments, the modern deflation basins are enclosed by parabolic dunes composed of clay and …
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Quaternary geology of Sargent County, North Dakota
… Sargent County were to (1) describe the surface sediment and interpret its origin, (2) correlate, where possible, this sediment with that of adjacent areas, and (3) recon struct the general geologic history of the county for the Quaternary Period. </p><p> A geologic map of the county was prepared …
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CHEMICAL AND PHYSICAL ANALYSIS OF LAMINATED SEDIMENT FORMED IN LOE POOL, CORNWALL
Laminated and annually-laminated sediments are found in Loe Pool. The origins of such laminations are investigated and evidence for their conditions of formation are presented. In all sediment analysed the combustion residue was greater than 80%, and in the black and grey annually-laminated …
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Pleistocene geology of the Grand Forks-Bemidji area, northwestern Minnesota
… to Holocene and include glacial, glaciofluvial, lacustrine, bog, eolian, and alluvial sediments.</p> <p>Sixteen power-auger test holes, two measured sections along the Red Lake River, two composite sections from earlier drilling pro grams and surface exposures were used to characterize seven near …
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Holocene climate and environmental dynamics on the Tristan da Cunha island group, South Atlantic
… from the central South Atlantic. Peat and lacustrine sediment sequences were retrieved from the Tristan da Cunha island group in the central South Atlantic. These sequences were analysed with a multiproxy approach including pollen analysis, measurements of total carbon, nitrogen and …
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A Glacial Sedimentary System in Northwest Spitzbergen
… been constructed using an integrated analysis of lacustrine, terrestrial and marine sediments. Thirty-four piston cores were taken from two series of linked lakes in Signedalen, fed by three small cirque glaciers. Six further cores were taken from the fjord inlet, Signehamna, into which meltwater …
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Stratigraphy and history of the Sakakawea Sequence, south-central North Dakota
… Formation (Wisconsinan) is mainly glacial sediment. The Emmons Formation (late Wisconsinan) is mainly glacial sediment. The Four Bears Formation (Wisconsinan) is mainly either fluvial or lacustrine sediment. The Coteau Formation (Holocene) is mostly fluvial, colluvial, or slough sediment. …
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The geologic history of Lake of the Woods, Minnesota, reconstructed using seismic-reflection imaging and sediment core analysis
… of the best-preserved sequences of Lake Agassiz sediments are found in remnant lake basins where erosional processes are less pronounced than in adjacent higher-elevation regions. Lake of the Woods (LOTW), Minnesota, is among the largest of the Lake Agassiz remnant lakes and is an ideal location …
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Hydrology across scales : sensitivity of East African lakes to climate changes
… interpretation of paleoclimate information from lacustrine sediment proxies. On the other hand, the sensitivity of rift lakes often provides paleoclimate records of excellent quality characterized by a high signal-to-noise ratio. This study aims at better understanding of the climate-proxy …
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Magnetic records from latest Triassic to earliest Jurassic red beds, Utah and Arizona, and from mid-Pleistocene lake beds, New Mexico
… framework to tie Triassic-Jurassic sedimentation in the southwest U.S.A to marine strata in the United Kingdom, Turkey, and Italy, and to the Pangean rift history including extrusive igneous rocks, preserved in Morocco, and in the Newark Basin, northeast U.S.A. In addition, …
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Thermokarst dynamics in central-eastern Beringia
… is recorded in paleoenvironmental archives. Lake sediments are important archives that allow reconstruction of local limnogeological processes as well as past environmental changes driven directly or indirectly by climate dynamics. This study aims at reconstructing Late Quaternary permafrost and …
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Surface water and groundwater in a changing climate: applications of hydrogeophysics and trend analysis to understand hydrologic systems
… are buried beneath thick (5 to 10 m) fine lacustrine sediment, indicating that they were first deposited in proglacial lakes, where their large pore space was infilled slowly with lake sediments over time. </p> <p>Multiple geophysical surveys were carried out to study the internal structure …