Successive shifts of the India-Africa transform plate boundary during the Late Cretaceous-Paleogene interval: Implications for ophiolite emplacement along transforms. (15th April 2020)

• Record Type: Journal Article
• Authors: Rodriguez, Mathieu; Huchon, Philippe; Chamot-Rooke, Nicolas; Fournier, Marc; Delescluse, Matthias; Smit, Jeroen; Plunder, Alexis; Calvès, Gérôme; Ninkabou, Dia; Pubellier, Manuel; François, Thomas; Agard, Philippe; Gorini, Christian
• Is Part Of: Journal of Asian earth sciences. Volume 191(2020)
• Publication Date: 2020-04-15
• Subjects: Transform boundaries -- Arabian Sea -- Masirah ophiolites; Earth sciences -- Asia -- Periodicals; Sciences de la terre -- Asie -- Périodiques; Earth sciences; Asia; Periodicals; 555.05
• DOI: 10.1016/j.jseaes.2019.104225
• Languages: English
• ISSNs: 1367-9120

Abstract

Highlights: The Late Cretaceous India-Africa Transform plate boundary is identified at Chain Ridge. The Paleogene India-Africa transform plate boundary is identified at the Chain Fracture Zone and within the Owen Basin. The Masirah ophiolites emplaced along a transform boundary. The oceanic lithosphere subducting nowadays beneath Makran derives from the East Somali Basin instead of Neotethys. Abstract: 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.