Linking submarine channel-levee facies and architecture to flow structure of turbidity currents: insights from flume tank experiments

Sedimentology ◽  
2017 ◽  
Vol 65 (3) ◽  
pp. 931-951 ◽  
Author(s):  
Jan de Leeuw ◽  
Joris T. Eggenhuisen ◽  
Matthieu J. B. Cartigny
Keyword(s):  
Flow Structure ◽  
Turbidity Currents ◽  
Submarine Channel

Flow structure of turbidity currents

Sedimentology ◽  
2002 ◽  
Vol 49 (3) ◽  
pp. 397-419 ◽  
Author(s):  
M. Felix
Keyword(s):  
Flow Structure ◽  
Turbidity Currents

scholarly journals How Do Deep-Sea Gravity Currents Transport Sediment So Far?

Eos ◽  
2018 ◽  
Vol 99 ◽  
Author(s):  
Terri Cook
Keyword(s):  
Deep Sea ◽  
Field Measurements ◽  
Gravity Currents ◽  
Turbidity Currents ◽  
Spiral Flow ◽  
Submarine Channel

The first field measurements of turbidity currents flowing around submarine channel bends indicate spiral flow plays a key role in keeping sediment suspended for hundreds of kilometers.

Character, spatial and temporal variation of turbidity currents on a source-to-sink scale.

2020 ◽  
Author(s):  
Kate Heerema ◽  
Peter Talling ◽  
Matthieu Cartigny ◽  
Gwyn Lintern ◽  
Cooper Stacey ◽  
...  
Keyword(s):  
Full Range ◽  
Turbidity Current ◽  
Spatial And Temporal Variation ◽  
Turbidity Currents ◽  
Deep Basin ◽  
Data Set ◽  
Sedimentary Deposits ◽  
Submarine Channel ◽  
Direct Measurements ◽  
Adcp Data

<p>Seafloor avalanches of sediment called turbidity currents are one of the principle mechanisms for moving sediments across our planet. However, turbidity currents are notoriously difficult to monitor directly in action, and we still mainly depend on their sedimentary deposits as well as physical and numerical models to understand their temporal and spatial evolution. In recent years, multiple studies have successfully made direct measurements within active turbidity currents at multiple sites along their pathway. However, these direct measurements are often limited to the upper reaches of submarine systems, only cover relatively short (few months to a couple of years) time scales, or have very few measurement stations (<3). To capture the full range of turbidity current types and recurrence times we need to combine direct monitoring with longer-term archives in sedimentary deposits. Here we present an unusual data set that extends from the submarine channel on the delta, to the final deposits in the deep basin. The dataset combines short-term (< 1 year) direct measurements of flows with long-term sediment deposits (dating back to about 100 years). This combination of data types allows us to understand turbidity current frequencies, runouts, heights and characteristics along an entire submarine system.  </p><p>We analyse data from Bute Inlet, which is a fjord in British Colombia, Canada. The entire turbidity current system stretches out for 80 km, with an incised submarine channel extending for 45 km. 46 Cores have been collected between 2015 and 2018. Simultaneously, direct measurements of the currents have been obtained in 2016 and 2018 using Acoustic Doppler Current Profilers (ADCPs) in the submarine channel.</p><p>Our objective is two-fold. First, we look at flow frequency over time and space. Visual logs of the sediment cores, as well as sediment accumulation rates for a selection of cores, are used to infer flow frequencies. We then use the ADCP data to understand more frequent and recent flows at 6 places along the channel. These ADCP measurements are used to infer frequencies which are not necessarily recorded in the deposits, and give additional insights into current-day activity. This allows us to reconstruct the change in frequency over space and time.</p><p>Second, we consider the variation in turbidity current character to understand how flows evolve along the channel. Facies determination and grain size data are used to infer turbidity current character. Cores along the channel, on terraces and in the deep basin are used to understand the spatial variation. Finally, comparison of deposits and monitoring (ADCP) data shows how submarine flows are recorded by their deposits.</p>

scholarly journals The stratigraphic evolution of a submarine channel: linking seafloor dynamics to depositional products

2020 ◽  
Vol 90 (7) ◽  
pp. 673-686
Author(s):  
Stephen M. Hubbard ◽  
Zane R. Jobe ◽  
Brian W. Romans ◽  
Jacob A. Covault ◽  
Zoltan Sylvester ◽  
...  
Keyword(s):  
Turbidity Currents ◽  
High Concentration ◽  
Bounding Surface ◽  
Cross Sectional ◽  
Genetic Link ◽  
Submarine Channel ◽  
Time Space ◽  
Stratigraphic Evolution ◽  
Geomorphic Surfaces ◽  
The Relationship

ABSTRACT We investigate the relationship between the cross-sectional geomorphic expression of a submarine channel as observed on the seafloor and the stratigraphic product of long-lived erosion, bypass, and sediment deposition. Specifically, by reconstructing the time–space evolution of an individual channel fill (i.e., channel element) exposed in outcrop, we establish a genetic link between thick-bedded channel-element-axis sandstone to thinly interbedded channel-element-margin deposits. Although the bounding surface between axis sandstone and margin thin beds is sharply defined, it is composed of a series of geomorphic surface segments of various ages; as such, the composite stratigraphic surface (∼ 17 m relief) was formed from numerous incision events that repeatedly sculpted the conduit. By demonstrating the origin of the stratigraphic surface, we conclude that geomorphic surfaces with 2–7 m of erosional relief were largely responsible for the observed intra-channel-element architecture (and ultimately, the composite 17-m-thick element). The widely documented channel element axis-to-margin architecture is a product of submarine-channel thalweg dynamics, primarily recording interactions between the seafloor and the basal high-concentration layers of channelized turbidity currents.

Experimental observation of the flow structure of turbidity currents

2011 ◽  
Vol 49 (2) ◽  
pp. 168-177 ◽  
Author(s):  
Zahra Nourmohammadi ◽  
Hossein Afshin ◽  
Bahar Firoozabadi
Keyword(s):  
Experimental Observation ◽  
Flow Structure ◽  
Turbidity Currents

3-D Simulation of Conservative and Non-Conservative Density Current

2006 ◽  
Author(s):  
S. Hormozi ◽  
B. Firoozabadi ◽  
H. Ghasvari Jahromi ◽  
S. M. H. Moosavi Hekmati
Keyword(s):  
Flow Structure ◽  
Environmental Flows ◽  
Three Dimensional ◽  
Turbidity Currents ◽  
Density Current ◽  
Density Currents ◽  
Straight Channel ◽  
Suspended Material ◽  
Series Of Experiments ◽  
Good Agreement

Flows generated by density differences are called gravity or density currents which are generic features of many environmental flows. These currents are classified as the conservative and non-conservative flows whether the buoyancy flux is conserved or changed respectively. In this paper, a low Reynolds k-ε turbulence model is used to simulate three dimensional density and turbidity currents. Also, a series of experiments were conducted in a straight channel to study the characteristics of the non-conservative density current. In experiments, Kaolin was used as the suspended material. Comparisons are made between conservative and non-conservative's height, concentration and velocity profiles of the current and their variations along the transverse intersections. Outcomes indicate that the presence of the particles influences the flow structure sensibly. The results are compared with the experiments and showed a good agreement.

Flow structure in sinuous submarine channels: Velocity and turbulence structure of an experimental submarine channel

2006 ◽  
Vol 229 (3-4) ◽  
pp. 241-257 ◽  
Author(s):  
Gareth M. Keevil ◽  
Jeff Peakall ◽  
James L. Best ◽  
Kathryn J. Amos
Keyword(s):  
Flow Structure ◽  
Turbulence Structure ◽  
Submarine Channels ◽  
Submarine Channel

Quasi-stationary flow structure in turbidity currents

2020 ◽  
Vol 35 (6) ◽  
pp. 659-665 ◽  
Author(s):  
Shun Nomura ◽  
Giovanni De Cesare ◽  
Mikito Furuichi ◽  
Yasushi Takeda ◽  
Hide Sakaguchi
Keyword(s):  
Flow Structure ◽  
Stationary Flow ◽  
Turbidity Currents
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