The trajectory of India towards Eurasia recorded by subducted slabs: implications for the fate of NeoTethys

The Neo-Tethys Ocean progressively closed after India separated from Gondwana at 130 Ma and converged towards Eurasia. In this study subducted slabs were mapped over a large region of the MITP08 global seismic tomography data (Li et al., 2008) including southern Asia and the Indian Ocean. A distinct swath of deep lower mantle slabs were mapped between 20°N to 20°S in a region bounded by present-day Madagascar and the Cocos Basin at 1000 to 2500 km depths. Other slabs were mapped below Present Day India and Eurasia at shallower 700 to 1500 km depths. These slabs closely correspond to the well-known path that India has taken northward towards Eurasia in the Indo-Atlantic moving hotspot reference. The slabs account for a large proportion of predicted lost and subducted Neotethyan lithosphere since 130 Ma. Here we present a plate tectonic reconstruction that incorporates these mapped slab constraints with the implication that a large portion of the Neo-Tethys Ocean was subducted below a northward-moving India and not Eurasia. 3D slab geometries were mapped using GoCad software. Slabs were structurally unfolded in GoCad to a spherical earth model. GPlates software was used to build plate tectonic reconstructions using the unfolded slabs.