Multi-stage India-Asia collision: Paleomagnetic constraints from Hazara-Kashmir syntaxis in the western Himalaya

Abstract

The India-Asia collision is the most spectacular, recent, and still active tectonic event of the Earth’s history, leading to the uplift of the Himalayan-Tibetan orogen, which has been explained through several hypothetical models. Still, controversy remains, such as how and when it occurred. Here we report a paleomagnetic study of Cretaceous-Tertiary marine sediments from the Tethyan Himalaya (TH) in the Hazara area, north Pakistan, which aims to constrain timing for the onset of the India-Asia collision and to confirm the validity of already proposed models, particularly in western Himalaya’s perspective. Our results suggest that the TH was located at a paleolatitude of 8.5°S ± 3.8° and 13.1°N ± 3.8° during the interval of ca. 84−79 Ma and 59−56 Ma, respectively. A comparison between paleopoles obtained from the current study and coeval ones of the India Plate indicates that the TH rifted from Greater India before the Late Cretaceous, generating the Tethys Himalaya Basin (THB). Our findings support a model for a multi-stage collision involving at least two major subduction systems. A collision of the TH with the Trans-Tethyan subduction system (TTSS) began first in Late Cretaceous-Early Paleocene times (ca. 65 Ma), followed by a later collision with Asia at 55−52 Ma. The onset of the collision between the TH (plus TTSS) and Asia could not have occurred earlier than 59−56 Ma in the western Himalaya. Subsequently, the India craton collided with the TH, resulting in the diachronous closure of the THB between ca. 50 and ca. 40 Ma from west to east. These findings are consistent with geological and geochemical evidence and have a broad implication for plate reconfigurations, global climate, and biodiversity of collisional processes.

Strengthening the argument for a large Greater India

“…Knowing the original surface area of Greater India is a key parameter to define the kinematics of the India–Asia collision, arguably one of the most important tectonic events to shape our planet in the Cenozoic. Some studies advocate a multistage collision model that divides the oceanic basin at the leading edge of India into multiple plates that subsequently became incorporated with the Asian plate ( 1 – 3 ). Other studies suggest that the northern margin of the Indian continent was a contiguous passive margin ( 4 , 5 ), or that consider the northern margin of Greater India consisted of hyperextended continental crust, with the upper crust becoming part of the Himalayan thrust belt and the lower crust being subducted ( 6 ), thereby suggesting India + Greater India behaved as a single plate that existed since at least the Early Cretaceous ( 7 , 8 ).…”

PaleogeneFicusleaves from India and their implications for fig evolution and diversification

“…This study does not comment on the origin of Ficus but suggests that Eurasia might be the center of origin and the Indian subcontinent was likely to be an integral part of the processes of diversification suggested by Xu et al (2011). Contact between the wandering Indian plate and Asia was initiated around 60 Ma, as suggested by recent studies (An et al, 2021;Bian et al, 2021;Guo et al, 2021;Jadoon et al, 2022), therefore, our conjecture is that a robust phylogenetic study, including the present fossils, is now required for a more precise estimation for the origin of Ficus.…”

Constraints on the timing of the India‐Asia collision and unroofing history of the Himalayan orogen using detrital zircon U‐Pb‐Hf and whole‐rock Sr‐Nd isotopes in Cretaceous‐Miocene Lesser Himalayan sedimentary rocks

“…40 Ma in its variants (Xiao, 2015; Yang et al, 2015); and 53–48 Ma in the North India Sea model (Yuan et al, 2021). More complex collision processes have also been proposed based on palaeomagnetic datasets (Jadoon et al, 2021; Yuan et al, 2022). At least three reasons account for the disaccord of palaeomagnetic datasets: (1) inclination shallowing biases for sedimentary samples (Huang et al, 2013; Tauxe, 2005); (2) the remagnetization effect for volcanic samples (Huang et al, 2015); and (3) whether sufficiently averaging out the palaeosecular variation of the Earth's magnetic field (Deenen et al, 2011).…”

“…40 Ma in its variants (Xiao, 2015;Yang et al, 2015); and 53-48 Ma in the North India Sea model (Yuan et al, 2021). More complex collision processes have also been proposed based on palaeomagnetic datasets (Jadoon et al, 2021;Yuan et al, 2022). At least three reasons account for the disaccord of palaeomagnetic datasets: (1) inclination shallowing biases for sedimentary samples (Huang et al, 2013;Tauxe, 2005);…”