Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika
The South American continent as we know it formed during the break-up of West Gondwana between 150 and 110 million years ago, when the South Atlantic Rift system evolved into the South Atlantic ocean. Using state-of-the-art global tectonic reconstructions in conjunction with numerical and analytical...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | German |
Published: |
2016
|
Subjects: | |
Online Access: | https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917891/GFZ_syserde.06.02.01.pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917892/GFZ_syserde.06.02.01_a.pdf |
id |
ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_1917890 |
---|---|
record_format |
openpolar |
spelling |
ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_1917890 2023-05-15T13:40:18+02:00 Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika Brune, S. Williams, S. Müller, R. Sobolev, S. 2016 application/pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917891/GFZ_syserde.06.02.01.pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917892/GFZ_syserde.06.02.01_a.pdf deu ger info:eu-repo/semantics/altIdentifier/doi/10.2312/GFZ.syserde.06.02.1 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917891/GFZ_syserde.06.02.01.pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917892/GFZ_syserde.06.02.01_a.pdf info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-sa/4.0/ CC-BY-SA System Erde info:eu-repo/semantics/article 2016 ftgfzpotsdam https://doi.org/10.2312/GFZ.syserde.06.02.1 2022-09-14T05:54:27Z The South American continent as we know it formed during the break-up of West Gondwana between 150 and 110 million years ago, when the South Atlantic Rift system evolved into the South Atlantic ocean. Using state-of-the-art global tectonic reconstructions in conjunction with numerical and analytical modelling, we investigate the geodynamics of rift systems as they evolve into an ocean basin. We find that rifts initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. In case of the split between South America and Africa, the divergence rate increased from initially 5 to 7 millimetres per year to over 40 millimetres per year within few million years. Intriguingly, abrupt rift acceleration did not only occur during the splitting of West Gondwana, but also during the separation of Australia and Antarctica, North America and Greenland, Africa and South America, in the North Atlantic or the South China Sea. We elucidate the underlying process by reproducing the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The mechanical models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength–velocity feedback similar to a rope that snaps when pulled apart. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time. Article in Journal/Newspaper Antarc* Antarctica Greenland North Atlantic South Atlantic Ocean GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) Greenland |
institution |
Open Polar |
collection |
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
op_collection_id |
ftgfzpotsdam |
language |
German |
description |
The South American continent as we know it formed during the break-up of West Gondwana between 150 and 110 million years ago, when the South Atlantic Rift system evolved into the South Atlantic ocean. Using state-of-the-art global tectonic reconstructions in conjunction with numerical and analytical modelling, we investigate the geodynamics of rift systems as they evolve into an ocean basin. We find that rifts initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. In case of the split between South America and Africa, the divergence rate increased from initially 5 to 7 millimetres per year to over 40 millimetres per year within few million years. Intriguingly, abrupt rift acceleration did not only occur during the splitting of West Gondwana, but also during the separation of Australia and Antarctica, North America and Greenland, Africa and South America, in the North Atlantic or the South China Sea. We elucidate the underlying process by reproducing the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The mechanical models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength–velocity feedback similar to a rope that snaps when pulled apart. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time. |
format |
Article in Journal/Newspaper |
author |
Brune, S. Williams, S. Müller, R. Sobolev, S. |
spellingShingle |
Brune, S. Williams, S. Müller, R. Sobolev, S. Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
author_facet |
Brune, S. Williams, S. Müller, R. Sobolev, S. |
author_sort |
Brune, S. |
title |
Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
title_short |
Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
title_full |
Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
title_fullStr |
Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
title_full_unstemmed |
Aus eins mach zwei: Geodynamische Modelle beschreiben Südamerikas Trennung von Afrika |
title_sort |
aus eins mach zwei: geodynamische modelle beschreiben südamerikas trennung von afrika |
publishDate |
2016 |
url |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917891/GFZ_syserde.06.02.01.pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917892/GFZ_syserde.06.02.01_a.pdf |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Antarc* Antarctica Greenland North Atlantic South Atlantic Ocean |
genre_facet |
Antarc* Antarctica Greenland North Atlantic South Atlantic Ocean |
op_source |
System Erde |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.2312/GFZ.syserde.06.02.1 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890 https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917891/GFZ_syserde.06.02.01.pdf https://gfzpublic.gfz-potsdam.de/pubman/item/item_1917890_2/component/file_1917892/GFZ_syserde.06.02.01_a.pdf |
op_rights |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-sa/4.0/ |
op_rightsnorm |
CC-BY-SA |
op_doi |
https://doi.org/10.2312/GFZ.syserde.06.02.1 |
_version_ |
1766132077807271936 |