A5087251009- Geological formations and processes
- Geology and Paleoclimatology Research
- earthquake and tectonic studies
- Methane Hydrates and Related Phenomena
- Landslides and related hazards
- Geological and Geophysical Studies
- Coastal wetland ecosystem dynamics
- Mercury impact and mitigation studies
- Reservoir Engineering and Simulation Methods
- Cryospheric studies and observations
- Geological and Tectonic Studies in Latin America
- Marine and coastal ecosystems
- Hydrology and Sediment Transport Processes
- Hydrocarbon exploration and reservoir analysis
- Isotope Analysis in Ecology
- Oceanographic and Atmospheric Processes
- Astronomical Observations and Instrumentation
- Microplastics and Plastic Pollution
- Geophysics and Gravity Measurements
- Inertial Sensor and Navigation
- CO2 Sequestration and Geologic Interactions
- Climate change and permafrost
- Marine Biology and Ecology Research
- Maritime and Coastal Archaeology
- Geological Modeling and Analysis
Durham University
2019-2024
University of Victoria
2022
Abstract Here we show how major rivers can efficiently connect to the deep-sea, by analysing longest runout sediment flows (of any type) yet measured in action on Earth. These seafloor turbidity currents originated from Congo River-mouth, with one flow travelling >1,130 km whilst accelerating 5.2 8.0 m/s. In year, these eroded 1,338-2,675 [>535-1,070] Mt of submarine canyon, equivalent 19–37 [>7–15] % annual suspended flux present-day rivers. It was known earthquakes trigger...
Seabed sediment flows called turbidity currents form some of the largest accumulations, deepest canyons and longest channel systems on Earth. Only rivers transport comparable volumes over such large areas; but there are far fewer measurements from currents, ensuring they much more poorly understood. Turbidity differ fundamentally rivers, as driven by that suspend. Fast can pick up sediment, self-accelerate (ignite); whilst slow deposit dissipate. Self-acceleration cannot continue...
Until recently, despite being one of the most important sediment transport phenomena on Earth, few direct measurements turbidity currents existed. Consequently, their structure and evolution were poorly understood, particularly whether they are dense or dilute. Here, we analyze largest number monitored to date from source sink. We show internal flow characteristic as runout. Observed frontal regions (heads) fast (>1.5 m/s), thin (<10 m), (depth averaged concentrations up 38%vol), strongly...
Abstract The delivery and burial of terrestrial particulate organic carbon (OC) in marine sediments is important to quantify, because this OC a food resource for benthic communities, if buried it may lower the concentrations atmospheric CO 2 over geologic timescales. Analysis sediment cores has previously shown that fjords are hotspots burial. Fjords can contain complex networks submarine channels formed by seafloor flows, called turbidity currents. However, efficiency distribution currents...
Abstract Landslide-dams, which are often transient, can strongly affect the geomorphology, and sediment geochemical fluxes, within subaerial fluvial systems. The potential occurrence impact of analogous landslide-dams in submarine canyons has, however, been difficult to determine due a scarcity sufficiently time-resolved observations. Here we present repeat bathymetric surveys major canyon, Congo Canyon, offshore West Africa, from 2005 2019. We show how an ~0.09 km 3 canyon-flank landslide...
ABSTRACT Turbidity currents triggered at river mouths form an important highway for sediment, organic carbon, and nutrients to the deep sea. Consequently, it has been proposed that deposits of these flood-triggered turbidity provide long-term records past floods, continental erosion, climate. Various depositional models have suggested identify river-flood-triggered turbidite deposits, which are largely based on assumption a characteristic velocity structure current is preserved as...
Submarine canyons and channels are globally important pathways for sediment, organic carbon, nutrients pollutants to the deep sea, they form largest sediment accumulations on Earth. However, studying these remote submarine systems comprehensively remains a challenge. In this study, we used only complete-coverage repeated bathymetric surveys yet very large system, which is Congo Fan off West Africa. Our aim understand channel-modifying features such as subaqueous landslides, meander-bend...
The largest canyons on Earth occur the seafloor, and seabed sediment flows called turbidity currents play a key role in carving these submarine canyons. However, processes by which erode are very poorly documented understood. Here we analyse first detailed time-lapse bathymetric surveys of large canyon, its continuation as less-deeply incised channel. These also most comprehensive before after major canyon-channel flushing current. unique field data come from Congo Submarine Fan offshore...
Abstract Turbidity currents carve the deepest canyons on Earth, deposit its largest sediment accumulations, and break seabed telecommunication cables. Powerful canyon‐flushing turbidity sensors placed in their path, making them notoriously challenging to measure, thus poorly understood. This study provides first remote measurements of flows, using ocean‐bottom seismographs located outside flow's destructive revolutionizing flow monitoring. We recorded internal dynamics longest flows yet...
Abstract Here we document for the first time how major rivers connect directly to deep-sea, by analysing longest runout sediment flows (of any type) yet measured in action. These seafloor turbidity currents originated from Congo River-mouth, with one flow travelling >1,130 km whilst accelerating 5.2 8.0 m/s. In year, these eroded 1-2 3 of just submarine canyon, equivalent 14-28% annual global-flux rivers. It was known earthquakes trigger canyon-flushing flows. We show river-floods also...
Seabed telecommunication cables can be damaged or broken by powerful seafloor flows of sediment (called turbidity currents), which may runout for hundreds kilometres into the deep ocean. These have potential to affect multiple near-simultaneously over very large areas, so it is more challenging reroute traffic repair cables. However, cable-breaking currents that ocean were poorly understood, and thus hard predict, as there no detailed measurements from these in action. Here we present first...
&lt;p&gt;Turbidity currents form many of the largest sediment accumulations, longest channels, and deepest canyons on our planet. These seabed avalanches can be very (&gt; 10 m/s) fast, runout for hundreds kilometres, break cables that now backbone internet global data transfer. It was once thought detailed monitoring turbidity in action impractical, ensuring these flows were relatively poorly understood. However, a series recent projects have used new approaches technology to...
Earth and Space Science Open Archive This preprint has been submitted to is under consideration at Journal of Geophysical Research - Biogeosciences. ESSOAr a venue for early communication or feedback before peer review. Data may be preliminary.Learn more about preprints preprintOpen AccessYou are viewing the latest version by default [v2]How turbidity currents dictate organic carbon fluxes across river-fed fjordsAuthorsSophieHageiDValierGalyMatthieu J.B.CartignyCatharinaHeeremaMaarten...
The increasing plastic pollution of the world&#8217;s oceans represents a serious threat to marine ecosystems and has become well-known topic garnering growing public attention. global input waste into is estimated be approximately 10 million tons per year predicted rise by one order magnitude 2025. More than 90% that enters thought end up on seafloor, seafloor sediment samples show plastics are concentrated in confined morphologies sedimentary environments such as submarine canyons....
&lt;p&gt;Seafloor avalanches of sediment called turbidity currents are one the principle mechanisms for moving sediments across our planet. However, notoriously difficult to monitor directly in action, and we still mainly depend on their sedimentary deposits as well physical numerical models understand temporal spatial evolution. In recent years, multiple studies have successfully made direct measurements within active at sites along pathway. these often limited upper reaches...
Earth and Space Science Open Archive This preprint has been submitted to is under consideration at Journal of Geophysical Research - Biogeosciences. ESSOAr a venue for early communication or feedback before peer review. Data may be preliminary.Learn more about preprints preprintOpen AccessYou are viewing an older version [v1]Go new versionHow turbidity currents dictate organic carbon fluxes across river-fed fjordsAuthorsSophieHageiDValierGalyMatthieu J.B.CartignyCatharinaHeeremaMaarten...
&lt;p&gt;Submarine canyons and channels include the largest sediment transport systems on our planet. They are an important pathway for sediment, organic carbon, nutrients pollutants to deep sea. However, it is challenging study these submarine locations, especially larger seafloor, they remain poorly understood. Here we use first extensive time-lapse bathymetric surveys of Congo Submarine Fan (offshore West Africa), one fans in world. Channel-modifying processes (such as landslides,...