Successive shifts of the India-Africa transform plate boundary during the Late Cretaceous-Paleogene interval: implications for ophiolite emplacement along transforms
|Author(s)||Rodriguez Mathieu1, Huchon Philippe2, Chamot-Rooke Nicolas1, Fournier Marc2, Delescluse Matthias1, Smit Jeroen3, Plunder Alexis2, Calvès Gérôme4, Ninkabou Dia1, 2, Pubellier Manuel1, François Thomas5, Agard Philippe2, Gorini Christian2|
|Affiliation(s)||1 : Laboratoire de Géologie, Ecole normale supérieure, PSL research university, CNRS UMR 8538, 24 rue Lhomond, 75005 Paris, France
2 : Sorbonne Université, CNRS-INSU, Institut des Sciences de la Terre de Paris, ISTeP UMR 7193, F- 75005 Paris, France
3 : Department of Earth Sciences, Utrecht University, PO box 80.021, 3508 TA, Utrecht, The Netherlands
4 : Université Toulouse 3, Paul Sabatier, OMP-GET, 14 Avenue Edouard Belin, 31400-F, Toulouse, France
5 : GEOPS, Univ. Paris-Sud, CNRS, Université Paris-Saclay, 91405 Orsay, France
|Source||Journal Of Asian Earth Sciences (1367-9120) (Elsevier BV), 2020-04 , Vol. 191 , P. 104225 (17p.)|
|WOS© Times Cited||7|
|Keyword(s)||Transform boundaries, Arabian Sea, Masirah ophiolites|
The Arabian Sea in the NW Indian Ocean is a place where two major transform boundaries are currently active : the Owen Fracture Zone between India and Arabia and the Owen Transform between India and Somalia. These transform systems result from the fragmentation of the India-Africa Transform boundary, which initiated about 90 Myrs ago, when the India-Seychelles block separated from Madagascar to move towards Eurasia. Therefore, the geological record of the Arabian Sea makes it possible to investigate the sensitivity of a transform system to several major geodynamic changes.
Here we focus on the evolution of the India-Africa transform system during the ∼47-90 Ma interval. We identify the Late Cretaceous (∼90-65 Ma) transform plate boundary along Chain Ridge, in the North Somali Basin. From 65 to ∼42-47 Ma, the India-Africa transform is identified at the Chain Fracture Zone, which crossed both the Owen Basin and the North East Oman margin. Finally, the transform system jumped to its present-day location in the vicinity of the Owen Ridge. These shifts of the India-Africa boundary with time provide a consistent paleogeographic framework for the emplacement of the Masirah Ophiolitic Belt, which constitutes a case of ophiolite emplaced along a transform boundary. The successive locations of the India-Africa boundary further highlight the origin of the Owen Basin lithosphere incoming into the Makran subduction zone.