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Showing 1 to 15 of 15 for “"Lacustrine deposits"”.
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Analysis of Lacustrine Deposits of Custer Lookout and Leftor Butte, Stark County, North Dakota
… These units are commonly considered to be of lacustrine origin, although no specific paleoenvironmental analysis has been conducted. The purpose of this research was to determine if petrographic or other laboratory evidence supports a lacustrine origin for these units. Methods included …
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Mammal and bird trackways in the Miocene Horse Spring Formation, Clark County, Nevada
… Miocene mammal and bird tracks associated with lacustrine deposits is beginning to become apparent.
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Late Holocene earthflows of the Willard Playa/dune complex, Estancia Valley, New Mexico; a geomorphic response to climatic change
… 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 gypsum derived …
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THE STRATIGRAPHIC POSITION OF FOSSIL VERTEBRATES FROM THE POJOAQUE MEMBER OF THE TESUQUE FORMATION (MIDDLE MIOCENE, LATE BARSTOVIAN) NEAR ESPAÑOLA, NEW MEXICO
… represented a dynamic alluvial fan-fluvial-lacustrine environment within the Española Basin while the Rio Grande Rift was active. Cavazza (1986) identified two paleodrainage systems (lithosome A, basin-margin facies and B, basin-floor facies) by means of sandstone and conglomerate petrology, …
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Neotectonic evolution of Grand Canyon : interaction between volcanism, river incision, epeirogenic uplift, and faulting
… of Grand Canyon's lava dams. Associated gravel deposits, internal cooling structures, and a general lack of lacustrine deposits suggests that the dams were removed in multiple stages and probably did not last for more than a few hundred to thousand years. Perched gravels under lava dams show …
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Terrestrial Impacts of the Central Atlantic Magmatic Province on western Pangea
… Point Member of the Moenave Formation is a lacustrine deposit with a disputed age of either late Triassic or early Jurassic and currently no absolute dating techniques can be applied to estimate an exact age. Therefore, I propose that identification of the CAMP carbon cycle perturbation …
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Organic influences on hydrated magnesium carbonate mineral formation
… carbonates thought to be associated with lacustrine deposits in Jezero Crater are an important target of the Mars Sample Return Mission. The presence of hydrated magnesium carbonates in the deposits suggests that these minerals experienced minimal postdepositional alteration and may have …
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Depositional environments of the lower Tullock Formation (Paleocene), Slope County, southwestern North Dakota
… paleo-raot systems. Well-drained swamp deposits are difficult to distinguish, but are probably located in the silt beds.</p> <p>There are two types of clay beds which were deposited in different envirorunents. The first type of clay bed is dark-colored, rich in organic matter, silty and …
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Age, Stratigraphy and Depositional Environment of the Pliocene Copper Canyon Formation, Death Valley, California
<p>The Copper Canyon Formation, a fluvial-lacustrine deposit exposed within the Black Mountains of Death Valley National Park, has only previously been broadly included in regional tectonic and depositional analyses. The formation is significant because it preserves numerous shoreline-playa …
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Estratigrafia de sequências do intervalo aptiano ao albiano na Bacia do Araripe, NE do Brasil
… characterized by fill channel and floodplain deposits; the facies of this system are associated vertically according to the textural thinning upward cycles (dirting-up trend pattern in well logs). Lacustrine environment is mainly related with the lithotypes of the Crato Formation, it shows a …
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Derivation of Acoustic and Physical Properties from High-Resolution Seismic Reflection Data
… and identify, previously unknown glacial and lacustrine deposits. The spectral-ratio technique was used to reliably estimate Q from seismic reflection data, without assumptions on how attenuation varies with frequency. Based on empirical observations, it is demonstrated here that Q can …
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Reservoir characterization and geology of the coals and carbonaceous shales of the Cherokee group in the Cherokee Basin, Kansas, Missouri and Oklahoma, U.S.A.
… in ascending order, are deep water marine or lacustrine deposits, rich in organic matter and are capable of generating gas. The primary gas productive coals in ascending order across the basin are the Riverton, the Rowe, the Weir-Pittsburg and the Mulky coals. The Aw, Neutral, Drywood, …
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Travertine from Egypt's Western Desert: a terrestrial record of North African paleohydrology and paleoclimate during the late Pleistocene
… ~450-600 ka. We also show that at least some lacustrine deposits at Dahkla Oasis associated with paleolithic artifacts are 300-350 ka rather than ~130 ka. A comparison of travertine geochemistry with modern groundwater chemistry suggests that a consistent Nubian groundwater source has fed …
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Paleoenvironment and paleoclimate of NE Pangea in early Permian-linking chemo- and cyclo-stratigraphy, Bogda Mountains, NW China
<p>"The overall objective of this study is to understand physical and chemical responses of Earth Systems to environmental and climatic perturbations of diverse magnitudes and time scales in Bogda Mountains, NE Pangea. Field investigations, petrographic observations, and geochemical analyses have …
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Depositional conditions, stratigraphic evolution, and allo- and autogenic controls of lower Permian non-marine carbonate rocks, Lucaogou low-order cycle, Bogda Mountains, NW china
… is to interpret the depositional conditions of lacustrine carbonate deposits of the lower Permian Lucaogou low-order cycle in the greater Turpan-Junggar continental rift basin, NW China. The depositional environments of ten carbonate lithofacies in the Tarlong-Taodonggou half graben and the …