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Showing 1 to 20 of 44 for “"turbidity currents"”.
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3-D Numerical Modeling of Turbidity Currents
<p>The hydrodynamics of density currents are difficult to study in the natural envi- ronment, whereas laboratory experiments are limited to small-scale flows, are time- consuming and are not necessarily easier when it comes to measuring flow properties or establishing relationships between the …
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Experimental study of reservoir turbidity currents venting
… on a laboratory flume to analyze the behavior of turbidity currents while using the pass-through sediment management technique of venting. The main focus was to explore and develop a better understanding of the streamwise flow velocity and suspended sediment concentration vertical profiles, and …
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Layer-averaged modeling of turbidity currents with a finite element method
… system of partial differential equations for a turbidity current flowing in deep ambient water. Since the standard Galerkin method yields spurious oscillations when applied to convection-dominated flows, the dissipative-Galerkin technique which has a selective damping property, is used. In order …
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Bedload Transport, Self Acceleration, Downstream Sorting, and Flow Dynamics of Turbidity Currents
The experiments reported here are performed in configuration to test the concept of an internal delta. Dissolved salt is used as a surrogate for the finer phase, and lightweight plastic particles are used as a surrogate for the coarser phase. The plastic particles are carried mostly as bedload. …
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Evolution of a non-cohesive granular bed subject to a succession of erosive turbidity currents
… granular bed subject to a succession of erosive turbidity currents to evaluate the applicability of a proposed interface model that prescribes a relationship between the bed shear stress and the local bed elevation and local bed slope. This study considered only the relationship between the local …
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Detrainment and Settling of Sediment in Turbidity Currents: A Study to Inform Deep Seabed Mining
… that the creation, and subsequent traveling, of turbidity currents across the seabed as a result of deep-sea mining will lead to impacts on a scale that is not yet entirely understood. Building on decades of studies on gravity currents (both related and unrelated to deep-sea mining) the focus of …
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Quantifying turbidity current interactions with topography
… our understanding of how transport properties of turbidity currents are mediated by interactions with seafloor topography, specifically channelized surfaces. Turbidity currents are responsible for crafting the morphology of continental margins. Unfortunately, very few direct observations exists …
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Bedforms and Gravity Underflows in Marine Environments
… the argument that supercritical density and turbidity currents can develop long-wavelength, upstream-migrating bedforms is presented for the first time. Additional experimental evidence of the coexistence of upstream-migrating antidunes and small-scale downstream-migrating ripples created by …
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Controls on sedimentation in submarine canyons: Nazare, Setubal and Cascais canyons, West Iberian Margin
… that, during the glacial stages, turbidity currents are the dominant process of<br/>sediment transport, erosion and deposition in these canyons. Turbidity currents are<br/>mostly in the form of small-volume, high-frequency events that are generated by fluvial<br/>and hydrodynamic …
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Turbidity current processes and deposits on the northwest African Margin
… background sedimentation, alongslope bottom currents, and downslope gravity flows. A large section of the margin can be classified as a fine-grained clastic slope apron, although the presence of numerous volcanic islands and seamounts leads to a more complex distribution of sedimentary …
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Sedimentology and Stratigraphy of Glacial Lake Souris, North Dakota: effects of a glacial-lake outburst
… outburst sediments: braided rivers, low-density turbidity currents (the dominant process), and high-density turbidity currents or modified grain flows. Most high-density flows resulted directly from the influx of the outburst or from continuous avalanching due to rapid sedimentation. Low-density …
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Quantifying channelized submarine depositional systems from bed to basin scale
The challenges of directly observing active turbidity currents necessitates the consideration of preserved deposits for deciphering the behavior of these systems. In this thesis, I take advantage 3-D subsurface seismic data and outcrop exposures to study turbidites at scales ranging from bed to …
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Kerogen variation in a Devonian half graben system
… influence of inflowing sediment and oxygen rich turbidity currents. The quiescent environment in this area allowed the greatest amount of laminite facies accumulation. It was found that high TOC (total organic carbon), H/C (hydrogen/carbon ratio) and spore numbers were associated with these areas …
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The evolution of a sand-rich basin-fill sequence in the Pendleian (Namurian,E1c)of North-West England
… features were cut by infrequent, high energy turbidity currents. They were filled by progradation of a coarse-grained turbidite sand-body deposited from smaller, more frequent turbidity currents trapped in the first-order channel. During this process, second-order channels were cut and filled …
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Cenozoic geology of the continental slope and rise off western Nova Scotia
… that slope canyons existed at that time. Abyssal currents eroded the upper rise and smoothed relief on the continental slope in the Oligocene and middle(?) Miocene. In the Miocene, turbidites may have ponded on the upper rise landward of seafloor highs uplifted by salt ridges or pillows. …
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Failure processes in submarine landslides: a geomorphological approach
… initial evacuation of the surface sediment as turbidity currents, the area failed<br/>as an extensive spread. The spreading blocks subsequently underwent higher displacement<br/>and remoulding, and were partly removed by debris flows and turbidity currents. The<br/>renewed instability within …
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Stratigraphy and sedimentology of the northern part of the upper Gazelle Formation, eastern Klamath Mountains, northern California
… indicative of deposition by low-density turbidity currents. The sandstones are green lithic graywackes composed of approximately 15% quartz, 30% plagioclase, and 55% volcanic lithic fragments. Geochemical analyses indicate that the sandstones were derived from an Ordovician-Silurian …
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Experimental and numerical modeling of submarine channel flow and morphodynamics
… as products of density-driven flows known as turbidity currents. The flow field and the morphodynamics of these channels, however, remain poorly understood due to dormancy of these systems during the present geologic time. Both laboratory and numerical modeling allow the study of submarine …
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The Geology of the Arakapas Fault Belt Area Troodos Massif, Cyprus
… mass transport processes (slides, slurries, turbidity currents). All these rocks were later intruded by serpentinite and cut by a closely related system of normal and reverse east-west faults. The petrography and geochemistry of the APB area basalts is investigated and compared to those from …
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The influence of steps topography on the behavior of density currents – a numerical study
… channel levees. These bed features are formed by turbidity currents, and in turn, influence the flow characteristics of the density currents and their sediment transport behavior, thus affecting sedimentation in the oceans. To explore the interaction between density currents and stepped …
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