Discrete Element Modeling of Southeast Asia's 3D Lithospheric Deformation During the Indian Collision

Abstract The Indian collision has deformed the eastern Asian continent in a multifaceted way, uplifting Tibet and surrounding mountains, activating ≥1,000 km‐long strike‐slip faults, opening Tertiary rifts oceanic basins up to ≈3,000 km away from Himalayas. Modeling such broad‐scale tectonics been challenging. While continent‐scale, lithospheric deformation appears have primarily taken‐up by long, narrow, inter‐connected shear‐zones with large offsets, contribution of processes as channel‐flow, collapse, delamination, etc… remained contentious. Here, based on increasing 4 G (Geological, Geophysical, Geochronological, Geodetic) evidence including kinematic timing constraints main mechanisms at play, we use Discrete Element (DE) simulate further understand evolution 3D strain across east Asia since onset collision, ≈55 Ma ago. planar, 50 million 2 , 125 km‐thick models are scaled for gravity. approach permits mega‐fault generation without pre‐arranged initial settings. results provide insight into fault birth, propagation motion, well mountain building plateau growth. They corroborate that continental crustal thickening alternated extrusion blocks rifted apart far field. Remarkably, changes boundary conditions or indentation rate, DE model also vindicates slip reversal along shear zones.