Turbidity currents in the ocean and lakes are driven by suspended sediment. The vertical profiles of velocity excess density shaped interaction between current bed as well ambient water above. We present results a set 74 experiments that focus on characteristics fractional saline turbidity flowing over mobile bed. gravity flows include flows, hybrid saline/turbidity pure current. use dissolved salt is surrogate for mud so fine it does not settle out readily. Thus, all can be considered to...

There is a growing need across different disciplines to develop better predictive tools for flow conditions of density and turbidity currents. Apart from resorting complex numerical modeling or expensive field measurements, little known about how estimate gravity parameters scarce available data they relate each other. This study presents new method normal flows channel morphology based on an extensive set laboratory measurements. The compilation consists 78 published works containing 1092...

Rapidly decelerating sediment-laden flows typically emplace confined sedimentary deposits. In the fluvial environment, when rivers reach lakes flow emplaces a subaerial delta with distinctive topset, foreset, and bottomset submarine turbidity currents undergoing rapid deceleration commonly wedges (i.e., deposits thinning in downstream direction). Froude-supercritical have an intrinsic self-regulating mechanism for deceleration, that faster they flow, more incorporate ambient sea water...

A self‐accelerating current is a particle‐driven gravity flow moving on sloping bottom whose velocity increases in the downstream direction as result of increasing suspended sediment concentration due to entrainment from bed. This implies that net balance between deposition onto bed and erosion into must be favorable latter; thus, larger mass particles being picked up suspension than settling out. The self‐accelerative stage cannot continue indefinitely. Either slope drops off point where...

Abstract Intense turbidity currents occur in the Malaylay Submarine Canyon off northern coast of Mindoro Island Philippines. They start very shallow waters at shelf break and reach deeper where a gas pipeline is located. The was displaced by current 2006 its rock berm damaged another 10 years later. Here we propose that they are triggered near mouth Baco rivers direct sediment resuspension transport to canyon heads typhoon-induced waves currents. We show these unlikely generate hyperpycnal...

Turbidity currents in the ocean are driven by suspended sediment. Yet results from surveys of modern sea floor and turbidite outcrops indicate that they capable transporting as bedload depositing particles coarse cobble sizes. While cannot drive turbidity currents, it can strongly influence nature deposits emplace. This paper reports on first set experiments which focus transport granular material density underflows. These underflows include saline flows, hybrid saline/turbidity a pure...

As a river-carrying sediment mixture aggrade, it creates stratigraphic signature that records this evolution. This stratigraphy is characterized by the vertical/horizontal variation of substrate grain size distribution. If river degrades, mines stratigraphy, and transfers so accessed farther downstream. Although several numerical models tracking creation/consumption are available, none has been tested against experiments under plane bed regime conditions. Here nine physical modelling...

Abstract A self‐accelerating current is a particle‐driven gravity flow moving on sloping bed whose velocity surges in the downstream direction as result of increasing suspended sediment concentration entrained from bed. This concept although introduced decades ago has proved elusive to be measured, but it critical explain evidence that turbidity currents are arguably leading process for conveying sediments down continental slope and beyond. It implies both increase due feedback loop up point...

The flow of deep-sea turbidity currents in meandering channels has been considerable recent interest. Here we focus on the secondary associated with a subaqueous bottom current channel. For simplicity, saline may be used as surrogate for driven by dilute suspension fine-grained sediment that does not easily settle out. In case open channel flow, i.e. rivers, classical Rozovskiian paradigm is often invoked to explain channels. This indicates near-bottom bend directed inward, toward inner...

A series of large-scale experiments on nonchannelized, depositional turbidity currents show the evolution and complex stratigraphy channel-lobe systems developed updip downdip a break in slope.Two different sets experimental with sediment concentrations were run.The results provided comparative picture gross structure fans, information their surfaces, growth sequences, times activity incised channels lobed features.In particular, data analysis focused on: (a) velocity suspended-sediment...

Despite of considerable research activity during the last decades uncertainties still remain in prediction Vortex Induced Vibrations (VIV) risers. Model tests risers subjected to current have been shown be a useful method for investigation VIV behavior with and without suppression devices. In order get further insight on risers, an extensive hydrodynamic test program riser models vortex-induced vibrations was undertaken winter 2010 by Shell Oil Company. The VIV-model campaign performed...

Abstract Tropical cyclones impose stresses on narrow and shallow continental shelves. The interaction of strong wind- wave-induced currents with the local topography near shore gives rise to complex flow sediment transport patterns. Considerable uncertainty remains initiation mechanisms turbidity currents, particularly in coastal oceanic settings subject extreme weather events. Here we use state-of-the-art numerical models investigate implications tropical cyclone-induced circulation...

This study focuses on a numerical model of turbidity currents with reversing buoyancy, i.e., flows that are rendered heavier than the ambient water due to presence suspended sediment but as sedimentation progresses become lighter difference in temperature or salinity. The considered here may be either pulsed events continuous flows. It is well known these subject buoyancy reversal. Flows issuing upstream sufficient load and thus form bottom underflow. As deposits downstream direction,...

Decelerating turbidity currents commonly emplace sedimentary wedges. Here wedge is used as a generic term for sediment deposit, the thickness of which gradually decreases in downdip direction. Examples wedges relevant to research reported here include a) deposits submarine minibasins, b) on zones lower slopes stepped profiles, and c) levees channels. In present work, configuration study flows that These consisted succession sustained saline density underflows, were surrogates driven by...

Management of fine sediments presents an important engineering and environmental problem. The active dredging large volumes from harbors reservoirs involves the use expensive equipments with operational costs. In several situations, however, passive systems can afford efficient low cost alternative. This work assesses feasibility eroding bed sediment by jet discharges subsequent transport in suspension ensuing turbidity current.A calibrated numerical model is applied to study flow capacity...

This paper addresses a practical problem: “What portion of fairing or strake coverage may be lost damaged, before the operator must take corrective measures?” explores effect fairings (the exposure length) on Vortex-Induced Vibration (VIV) flexible cylinders. The source data is recent model test, conducted by SHELL Exploration and Production. A 38m long pipe with varying amounts was tested. Response as function percent length reported. Unexpected results are also reported: (i) ribbon used in...

Sediment management in reservoirs with the help of water jets has motivated this work. Erosion caused by single and multiple submerged circular turbulent wall on a noncohesive sediment bed finite thickness lying fixed boundary was studied laboratory experiments. Different combinations jet diameter, separation, to diameter ratio were tested. Results show relation between dimensionless parameters characterizing steady state profile densimetric particle Froude number F0 given velocity at nozzle...