Plume-MOR decoupling and the timing of India-Eurasia collision

Haytham Sehsah; Harald Furnes; Luan Thanh Pham; Ahmed M Eldosouky

doi:10.1038/s41598-022-16981-y

Plume-MOR decoupling and the timing of India-Eurasia collision

Sci Rep. 2022 Aug 3;12(1):13349. doi: 10.1038/s41598-022-16981-y.

Authors

Haytham Sehsah¹, Harald Furnes², Luan Thanh Pham³, Ahmed M Eldosouky⁴

Affiliations

¹ Geology Department, Faculty of Science, Damietta University, New Damietta, Damietta, 34517, Egypt. haytham_sehsah@du.edu.eg.
² Department of Earth Science, University of Bergen, Allegt. 41, 5007, Bergen, Norway.
³ Department of Geophysics, Faculty of Physics, University of Science, Vietnam National University, Hanoi, Vietnam.
⁴ Geology Department, Faculty of Science, Suez University, Suez, 43518, Egypt.

Abstract

The debatable timing of India-Eurasia collision is based on geologic, stratigraphic, kinematic, and tectonic evidence. However, the collision event disturbed persistent processes, and the timing of disturbance in such processes could determine the onset of India-Eurasia collision precisely. We use the longevity of Southeast Indian Ridge (SEIR)-Kerguelen mantle plume (KMP) interaction cycles along the Ninetyeast ridge (NER) as a proxy to determine the commencement of India-Eurasia collision. The geochemical signature of the KMP tail along the NER is predominantly that of long-term coupling cycles, that was perturbed once by a short-term decoupling cycle. The long-term coupling cycles are mainly of enriched mid-ocean ridge basalts (E-MORBs). The short-term decoupling cycle is mostly derived from two distinct sources, MOR and plume separately, whereas the KMP is still being on-axis. The onset of India-Eurasia collision led to continental materials recycling into the mantle; hence the abrupt enrichment in incompatible elements at ca. 55 Ma, the MOR-plume on-axis decoupling, and the abrupt slowdown in the northward drift of the Indian plate was induced by the onset of India-Eurasia collision, thereafter MOR-plume recoupled.