4D forward stratigraphic modelling of the late Quaternary Congo deep-sea fan: Role of climate/vegetation coupling in architectural evolution

Autor: Stéphane Molliex, Laurence Droz, Tania Marsset, Marina Rabineau, Marie Picot, Dimitri Laurent, Didier Granjeon
Přispěvatelé: Unité de recherche Géosciences Marines (Ifremer) (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), IFP Energies nouvelles (IFPEN), Laboratoire Géodynamique et enregistrement Sédimentaire (LGS), Géosciences Marines (GM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
Jazyk: angličtina
Rok vydání: 2020
Předmět:
010504 meteorology & atmospheric sciences
Sedimentary cycles
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences
DionisosFlow (TM)
010502 geochemistry & geophysics
Oceanography
Monsoon
Palaeoclimate
01 natural sciences
Deep sea
palaeoclimate
Quaternary
Paleontology
Geochemistry and Petrology
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry
DionisosFlow TM
Stratigraphic modelling
geophysical data
0105 earth and related environmental sciences
Turbidite system
sedimentary cycles
Deep-sea fan
Sediment
Geology
Vegetation
Vegetation/climate coupling
Sedimentation
vegetation/climate coupling
Turbidite
Geophysical data
Congo
13. Climate action
[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology
[SDE]Environmental Sciences
deep-sea fan
stratigraphic modelling
Sedimentary rock
turbidite system
Zdroj: Marine Geology (0025-3227) (Elsevier BV), 2020-11, Vol. 429, P. 106334 (22p.)
Marine Geology
Marine Geology, Elsevier, 2020, 429, pp.106334. ⟨10.1016/j.margeo.2020.106334⟩
Marine Geology, 2020, 429, pp.106334. ⟨10.1016/j.margeo.2020.106334⟩
ISSN: 0025-3227
DOI: 10.1016/j.margeo.2020.106334⟩
Popis: International audience; The relative impacts of autogenic and allogenic controls on the architectural evolution of deep-sea fans are not well constrained, mainly because of the difficulty in evaluating the role of each control on any specific stratigraphic pattern. This study presents four-dimensional (4D) forward stratigraphic modelling of the Late Quaternary Congo Axial Fan, which provides new insights on forcing factors of sedimentation over time. This modelling is based on a geological model describing successive sedimentary progradational/retrogradational cycles in the Congo turbidite system during the last 38 kyr. Analyses of geophysical and marine core data have suggested that the architectural cycles were controlled by changes in fluvial sediment discharge in relation to arid and humid periods in the Congo River watershed. The aims of this study were to simulate the architectural evolution of the Late Quaternary Congo Axial Fan from 210 ka to the present and investigate the factors controlling sedimentation using DionisosFlow™, a process-based stratigraphic forward modelling software. For this objective, several scenarios were tested to simulate the role of autogenic and climate forcings based on proxies recorded in marine sediments. The modelling results confirmed that climatic variations of sediment and water discharge succeeded in reproducing the timing, position, and sediment volume of basin-scale progradational/retrogradational cycles. The best-fit simulations particularly emphasise the role of continental vegetation cover expansion, governed by the precession-driven West African monsoon, on the sediment flux to the deep-marine environment. This vegetation/climate coupling acts directly on the transport capacity of flow over time by controlling the magnitude of river runoff and the timing of sediment production, storage, and transfer from the continent to the ocean. Thus, our results confirm the utility of stratigraphic forward models in constraining “source-to-sink” models for the architectural evolution of submarine fans.
Databáze: OpenAIRE
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