Paleogeography of the southern Eurasian margin in the lead-up to India-Eurasia collision
Prior to the India-Eurasia collision, the southern Eurasian margin either resembled a Cordillera-style accretionary orogen or a complex Japan-Mariana-style margin with extended back-arc basins and oceanic crust separating volcanic arc(s) from Eurasian continental lithosphere. Distinguishing between these alternative scenarios has implications for the convergence history of India and Eurasia, the development of the India-Eurasia collision zone, and the post-collision structure of the Himalayan orogen. In this presentation I will overview the geological constraints on the India-Eurasia collision in Northwest India and Pakistan, which show that a significant back-arc basin developed in the Late Cretaceous between the Kohistan-Ladakh arc and Eurasia. The Kohistan-Ladakh arc initially intruded a Jurassic forearc ophiolite at the southern edge of Eurasia before drifting southward in the Late Cretaceous during a period of Neotethyan slab rollback. The southward migration of the Kohistan-Ladakh arc away from Eurasia persisted until the Paleocene accretion of the Kohistan-Ladakh arc onto India. Final India-Eurasia continental collision occurred in the Lutetian when the Karakoram terrane was thrust over the Kohistan-Ladakh arc during the formation of the Shyok suture zone. So, at least in the western Himalaya, the Late Cretaceous to Paleocene southern Eurasian margin more closely resembled a Japan-Mariana-style system than a Cordilleran-style orogen. This conclusion is consistent with the paleogeography of the Neotethys Ocean to the East and West of the India-Eurasia collision zone, which is typified by complex southward arc migration, back-arc basin development, and multiple collision events.
Date: 22 November 2024, 12:00 (Friday, 6th week, Michaelmas 2024)
Venue: Seminar Rooms
Speaker: Dr Craig Martin (University of Texas at Austin)
Part of: Earth Sciences departmental seminars
Booking required?: Not required
Booking url: https://www.earth.ox.ac.uk/event/paleogeography-of-the-southern-eurasian-margin-in-the-lead-up-to-india-eurasia-collision
Audience: Public
Editor: Maria Petrunova