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| Titel |
Does strike-slip motion facilitate rifting and continental break-up? |
| VerfasserIn |
Sascha Brune, Anton A. Popov, Stephan V. Sobolev |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250038697
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| Zusammenfassung |
| Initial stages of continental break-up often involve large strike-slip components (e.g. during separation of South America and Africa, ~140 Ma) however there is no clear understanding of how oblique motions effect the break-up development. We use the three-dimensional, thermomechanical FEM code SLIM3D to model rifting of continental lithosphere composed of upper crust, lower crust, and mantle lithosphere. Results show that the force needed to initiate break-up strongly decreases for increased oblique plate motion. Our numerical models allow to quantify the relative importance of the three main weakening mechanisms: (i) friction softening in the brittle domain due to a strain-dependent effective angle of internal friction, as well as (ii) strain rate softening and (iii) shear heating which both reduce viscosity in the ductile domain. |
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