Cenozoic siliciclastic sediment budget at continent-scale, Africa.
International audience Siliciclastic sediment budget measurements was performed along the margins and onshore basins of Africa for Cenozoic times. Our objective was first to quantify the ratio between onshore and offshore sediment preservation in the case of a relief with mostly no mountain belt and...
Main Authors: | , , , |
---|---|
Other Authors: | , , , , , , |
Format: | Conference Object |
Language: | English |
Published: |
HAL CCSD
2013
|
Subjects: | |
Online Access: | https://hal-insu.archives-ouvertes.fr/insu-00853376 |
id |
ftccsdartic:oai:HAL:insu-00853376v1 |
---|---|
record_format |
openpolar |
spelling |
ftccsdartic:oai:HAL:insu-00853376v1 2023-05-15T18:21:15+02:00 Cenozoic siliciclastic sediment budget at continent-scale, Africa. Guillocheau, François Robin, Cécile Calves, Gérôme Baby, Guillaume Géosciences Rennes (GR) Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1) Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES) Géosciences Environnement Toulouse (GET) Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP) Météo France-Centre National d'Études Spatiales Toulouse (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD) Vienne, Austria 2013-04 https://hal-insu.archives-ouvertes.fr/insu-00853376 en eng HAL CCSD insu-00853376 https://hal-insu.archives-ouvertes.fr/insu-00853376 BIBCODE: 2013EGUGA.1512482G Geophysical Research Abstracts EGU General Assembly 2013 https://hal-insu.archives-ouvertes.fr/insu-00853376 EGU General Assembly 2013, Apr 2013, Vienne, Austria. pp.EGU2013-12482 [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/conferenceObject Conference papers 2013 ftccsdartic 2021-10-24T14:43:45Z International audience Siliciclastic sediment budget measurements was performed along the margins and onshore basins of Africa for Cenozoic times. Our objective was first to quantify the ratio between onshore and offshore sediment preservation in the case of a relief with mostly no mountain belt and secondly to understand the factors forcing the sediment supply along the passive margins of Africa that can be long to very-long relief deformation (mantle dynamics, ridge push.) or climate changes (with the major aridification of Africa since Middle Miocene). This study is based on basin-scale regional sections (seismic reflection data from industry and academics, wells correlation), calibrated in age and lithology on different types of wells (industry, DSDP/ODP). Most of the effort was on the revaluation of the ages (calibration and uncertainties). The volumes of sediments and uncertainties on depth conversion velocity laws, lithology and ages were measured using software developed by J. Braun (Grenoble University, France). * The sediment preserved onshore (750 000 km3) is one of magnitude less than was is preserved offshore * The main deformations controlling the sediment supply are (1) the growth or the domes of the East African rift and (2) the marginal bulge of the central and equatorial segments of the South Atlantic Ocean (from southern Angola to Guinea). * The aridification of Africa since at least Middle Miocene is very sensitive in the south (fossilization of the relief of the South African Plateau) and in the northwest, with a sharp decrease of the sediment supply. * Some buffer effects are very important, for example for the Nile and the Zambezi, where sediments were first stored in onshore basins, Sudan or Malawi rift, and later drained because of a capture (Nile) or a regional stress change (Zambezi). Keywords: Africa, Cenozoic, Siliciclastic sediment fluxes, Deformation, Climate Conference Object South Atlantic Ocean Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Guillocheau, François Robin, Cécile Calves, Gérôme Baby, Guillaume Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Siliciclastic sediment budget measurements was performed along the margins and onshore basins of Africa for Cenozoic times. Our objective was first to quantify the ratio between onshore and offshore sediment preservation in the case of a relief with mostly no mountain belt and secondly to understand the factors forcing the sediment supply along the passive margins of Africa that can be long to very-long relief deformation (mantle dynamics, ridge push.) or climate changes (with the major aridification of Africa since Middle Miocene). This study is based on basin-scale regional sections (seismic reflection data from industry and academics, wells correlation), calibrated in age and lithology on different types of wells (industry, DSDP/ODP). Most of the effort was on the revaluation of the ages (calibration and uncertainties). The volumes of sediments and uncertainties on depth conversion velocity laws, lithology and ages were measured using software developed by J. Braun (Grenoble University, France). * The sediment preserved onshore (750 000 km3) is one of magnitude less than was is preserved offshore * The main deformations controlling the sediment supply are (1) the growth or the domes of the East African rift and (2) the marginal bulge of the central and equatorial segments of the South Atlantic Ocean (from southern Angola to Guinea). * The aridification of Africa since at least Middle Miocene is very sensitive in the south (fossilization of the relief of the South African Plateau) and in the northwest, with a sharp decrease of the sediment supply. * Some buffer effects are very important, for example for the Nile and the Zambezi, where sediments were first stored in onshore basins, Sudan or Malawi rift, and later drained because of a capture (Nile) or a regional stress change (Zambezi). Keywords: Africa, Cenozoic, Siliciclastic sediment fluxes, Deformation, Climate |
author2 |
Géosciences Rennes (GR) Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1) Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES) Géosciences Environnement Toulouse (GET) Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP) Météo France-Centre National d'Études Spatiales Toulouse (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD) |
format |
Conference Object |
author |
Guillocheau, François Robin, Cécile Calves, Gérôme Baby, Guillaume |
author_facet |
Guillocheau, François Robin, Cécile Calves, Gérôme Baby, Guillaume |
author_sort |
Guillocheau, François |
title |
Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
title_short |
Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
title_full |
Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
title_fullStr |
Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
title_full_unstemmed |
Cenozoic siliciclastic sediment budget at continent-scale, Africa. |
title_sort |
cenozoic siliciclastic sediment budget at continent-scale, africa. |
publisher |
HAL CCSD |
publishDate |
2013 |
url |
https://hal-insu.archives-ouvertes.fr/insu-00853376 |
op_coverage |
Vienne, Austria |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
Geophysical Research Abstracts EGU General Assembly 2013 https://hal-insu.archives-ouvertes.fr/insu-00853376 EGU General Assembly 2013, Apr 2013, Vienne, Austria. pp.EGU2013-12482 |
op_relation |
insu-00853376 https://hal-insu.archives-ouvertes.fr/insu-00853376 BIBCODE: 2013EGUGA.1512482G |
_version_ |
1766200428181061632 |