Evolution of the foreland basins on either side of the Tian Shan and implications for lithospheric architecture

The previous understanding of Tian Shan's lithospheric architecture can be summarized into three models: unidirectional underthrusting, bidirectional and mantle upwelling. These models make distinctive predictions regarding the migration subsidence histories foreland basins on either side range. Seismic profiles crossing both document their history. We analyze a seismic profile across Southern Junggar basin (SJFB) to north range, which demonstrates that migrated northward at ∼3.1 mm/yr during 22–16 Ma. Combining this with previously known rates Northern Tarim (NTFB) south we constrain these two relative basements. then employ an elastic plate model simulate ∼20 Ma, 13–16 ∼5 0 Ma constrained by back stripping well log data records onlaps. Our modelling reveals propagation southern northern Shan thrust wedges evolution topographic loads. analysis demonstrate NTFB has characteristics retro-foreland basin, whereas SJFB resembles pro-foreland early-middle Miocene times. This suggests growth period was dominated underthrusting lithosphere. Furthermore, our reveal convergent pattern between lithosphere changed from indentation subduction after middle Miocene, as setting changed. had begun uplift before orogen's height reaching half its present elevation late Miocene.