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Showing 1 to 13 of 13 for “"Cross-stratification"”.
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Flume studies of large-scale cross-stratification produced by migrating bed forms
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1981.
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High- and low-sinuosity stream deposits of the Sentinel Butte Formation (Paleocene) McKenzie County, North Dakota
… an erosional base. The sand beds contain epsilon cross-stratification, within which stratification changes upward from large-scale trough crossstratification to horizontal stratification and small-scale crossstratification, indicating upward decrease in flow regime due to accretion of …
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Depositional environments of the upper part of the Sentinel Butte Formation, southeastern McKenzie County, North Dakota
… interpreted as channel plug deposits. Epsilon cross-strata are common. Cross-stratification grades from large-scale at the base to small scale at the top of the bed and grain size decreases upward. </p><p> An elongate, trough-shaped sand bed 15 meters thick and 400 meters wide and an elongated …
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Depositional environments of the lower Tullock Formation (Paleocene), Slope County, southwestern North Dakota
… are wedge-shaped and contain climbing ripple cross-stratification, interbedded sand lenses and lignitized 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 …
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Stratigraphy And Depositional Environments Of Lower And Middle Cambrian Strata In The Lake Mead Region, Southern Nevada And Northwestern Arizona
… and flaser-bedding, wrinkle marks, herringbone cross-stratification, convolute bedding, primary current lineations, interference ripple marks, bird's eye structures, thrombolites, intraformational conglomerates, oncoids, cryptalgal laminites, and Arenicoloides, Corophioides, and Skolithos …
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High-Resolution Correlation of a Time-Bounded Unit of the Pisco Formation, Peru
<p>Correlation of beds in the Pisco Basin across significant distances is problematic and has not yet been effectively achieved. I chose to examine an interval bounded by two time markers, an 40Ar/39Ar-dated white tuff at the base and an 40Ar/39Ar-dated tuff couplet at the top. This interval was …
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Sedimentology of Marine Vertebrate Burial in the Miocene Pisco Fm., Peru
… to locate 10 outcrops containing specimens in cross section, which allowed us to do detailed sedimentological studies of the beds surrounding the whales. We discovered that six of the 10 specimens were buried in channels; the details of the other four burials are too disparate to meaningfully …
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Storm-dominated shelf sedimentation marginal to a delta: an example from the Devonian of southwestern Virginia and eastern West Virginia
… of sequence types characterized by hummocky cross stratification. Individual beds usually have sharp erosive bases and gradational tops. A hydrodynamic interpretation of hummocky sequences suggests that they are the result of extremely large but infrequent storm events and are surrounded by …
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Paleoenvironmental Reconstruction of an Upper Ordovician Rocky Shoreline: The Lindsay Formation of Heywood and Partridge Islands, Ontario
… an outer ramp setting. The presence of hummocky cross-stratification, tempestites, large-scale wave ripples, and fragmented and disarticulated fossils, combined with the abundance of quartz clasts in the carbonate and mudstone units indicates frequent influence of storm activity during deposition.
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The stratigraphy and sedimentology of the Sentinel Butte Formation (Paleocene) in south-central Williams County, North Dakota
… sandstones, and the identification of epsilon cross-stratification in the tabular sandstones support a fluvial origin for some of the strata. The strongest evidence for the interpretation of lacustrine deposition is the presence of limestone bodies within these strata. Examination of thin …
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Sedimentology of the Bullion Creek and Sentinel Butte formations (Paleocene) in a part of southern McKenzie County, North Dakota
… within the channel fill include large-scale cross-stratification, climbing-ripple cross-lamination, and planar lamination. Also included at various levels within channel fills are claystone lag-gravel accumulations.</p> <p>Two types of channels are present in the Sentinel Butte Formation. A …
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Interpretation of coarsening upwards hemicycles in the Upper Paleozoic rocks of South-central West Virginia
… of channel parameters (from epsilon cross-stratification, channel fill width, channel depth and channel perimeter silt and clay percentage) indicate that most of the Carboniferous paleochannel were relatively small and had a mean annual discharge in the range of 1800 to 5100 cfs, …
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Geo- and biodynamic evolution at the northern margin of Gondwana during Late Silurian to Early Devonian time (Hazro Area, SE Turkey)
… and tide driven forces as documented by swaley cross stratification, mud drapings and a high mineralogical and textural maturity. The two successive progradational sequences of the 5th order were separated from each other by a period of non-deposition and erosion, which is reflected by the …