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The Tarim Basin Craton is located in the center of the Tarim Basin. Since the beginning of the Miocene, the tectonic activity has been weaker in the Tarim Basin Craton than in the marginal depression and the peripheral orogenic belts. This study investigates the tectonic movements in the Tarim Basin Craton by calculating the sedimentation rates and constructing balanced cross-sections based on well, seismic and geologic data. The tectonic movements in the Tarim Basin Craton have mainly been revealed by geological processes such as sedimentation and subsidence, structural inversion, changes in the structural feature, migration of the structural highs, and faulting. The Neogene sedimentary strata were mainly deposited in two sedimentation centers, the southern and northern sedimentation centers, and the strata in the Central Uplift Zone are relatively thin. The different depressions in different geological periods experienced wide variations in tectonic activity. Tectonic subsidence was significant and the sedimentation rates were high in the Tarim Basin Craton during the Pliocene Period (phase II). During the Neotectonic period, the stresses in the South-North direction converged in the Central Uplift Zone (the Bachu uplift-Central Tarim uplift), and the tectonic activity in this region was more intense than that in the Northern Depression and the Maigaiti Slope in the southwest. In addition, the scale of the paleo-uplift, including paleo-North Tarim Uplift and paleo-Central Uplift Zone, gradually decreased. The faults and fault systems developed zonationally in Neotectonic formations in different structural units, and always distributed discontinuously in vertical direction in sections. [ABSTRACT FROM AUTHOR]

Abstract: Coarse clastic rocks, developed widely at foredeep adjacent to orogene, were usually regarded as the mark of renewed thrusting action. However a good example from the Lower Cretaceous in Kuqa foreland sub-basin illustrated that the coarse clastic rocks developed not only in initial thrusting stage but in early quiescence stage. The Kuqa foreland sub-basin, adjacent to the south Tianshan Orogene, lies to the north of Tarim Basin, northwest China. The Lower Cretaceous outcrop in the front of south Tianshan Orogene was identified as a filling sequence of foredeep which includes two depositional cycles of Kapushaliang Group and Bashijiqike Formation. Each of them presents fining-upwards and then coarsening-upwards sequences. Two lithosomes of coarse clastic rocks developed in the lower of Yageliemu Formation of Kapushaliang Group and Bashijiqike Formation, respectively. Both of them are mainly composed of thick-bedded, massive and chaotic conglomerate with debris flow microfacies of fan delta plain. The analyses on stratigraphic and depositional records for tectonism revealed abrupt sedimentary change from delta facies to fan delta facies, stratal geometry transformation, and reflection termination migration of truncation and top-lap between the Kapushaliang Group and the Bashijiqike Formation. These records indicated that: foredeep subsided rapidly while forebulge uplifted in the development of Kapushaliang Group, which coincided perfectly with lithosphere deformation during thrusting stage; foredeep uplifted rapidly while forebulge subsided in the later development of Bashijiqike Formation, which coincided with lithosphere deformation during quiescence stage of foreland basin development. Therefore, the Lower Cretaceous recorded a whole episode of foreland basin evolution from earlier thrusting to later quiescence. The underfilled cycle of Kapushaliang Group, corresponding to the thrusting stage, is much thick with mainly muddy and silty sediments. The overfilled cycle of Bashijiqike Formation, corresponding to the quiescence stage, is thin with mainly sandy sediments. The two lithosomes of coarse clastic rocks were very similar with each other in the lithology and sedimentology. However, the one from lower Yageliemu Formation is responded to the renewed thrusting, but the other from the lower Bashijiqike Formation is responded to the lithosphere rebounding during primary quiescence stage. Therefore, cannot only coarse clastic rocks indicated a renewed thrusting. [Copyright &y& Elsevier]