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The Cenozoic sediments are very thick in the southwest Tarim Basin and very thin in the northwest, but what controls these variations is unclear. Here, we use two‐dimensional thermo‐mechanical models to investigate how the lateral variations in rheological strength and depletion density of cratonic lithosphere mantle affect the cratonic basin deformation. Model results show that the basin basement uplift occurs above either the region with crustal thickening or high depletion in the mantle. A model with a stronger and density‐depleted northern half of cratonic lithosphere mantle in the context of compression matches the differential Cenozoic subsidence and deformation observed in the Tarim Basin well. We propose that a Permian plume led to the lateral heterogeneity of the lithosphere mantle under the Tarim craton, and the modified lithosphere mantle characteristics caused the differential Cenozoic sediment thickness in the Tarim Basin. Plain Language Summary: Tarim Basin is a typical intraplate cratonic basin in northwest China. It is bounded by the West Kunlun Shan to the south and the Tian Shan to the north, respectively. The Cenozoic sediment thickness in the Tarim Basin displays significant lateral variation, which cannot be explained by flexural bending of the Tarim lithosphere under orogenic loads of the West Kunlun Shan and Tian Shan. Recent geophysical data outlined the extent of the Permian plume head, which coincides with the region covered by thinnest Cenozoic sediments. Here, we conduct a series of 2‐D thermo‐mechanical numerical simulations to examine the correlation of the cratonic lithosphere mantle characteristics with cratonic basin's basement geometry. Model results show that a craton with a stronger and density‐depleted northern half of lithosphere mantle in the context of compression matches well with the south‐north differential Cenozoic subsidence and deformation in the Tarim Basin. Accordingly, we suggest that the differential Cenozoic sediment thickness in the Tarim Basin was likely caused by the Permian plume‐modified lithosphere mantle. Our study indicates that the plume‐modified mantle characteristics play a critical role in the basement deformation of the above sediment basin. Key Points: The strength and depletion density of cratonic lithosphere mantle control the deformation of cratonic lithosphere underlying sediment basinThe differential Cenozoic sediment thickness in the Tarim Basin is related to the heterogeneity of cratonic lithosphere mantleThe lithosphere mantle heterogeneity under the Tarim craton was likely caused by post‐Permian plume‐driven recratonization [ABSTRACT FROM AUTHOR]

The India–Eurasia collision has produced a number of Cenozoic deep intracontinental basins, which bear important information for revealing the far‐afield responses to the remote collision. Despite their significance, their subsiding mechanism remains the subject of debate, with end‐member models attributing it to either orogenic or sedimentary load. In this study, we conduct flexural subsidence modeling with a two‐dimensional finite elastic plate model on the Hotan–Mazatagh section along the southern Tarim Basin, which defines a key region in the foreland of the West Kunlun Orogen, along the NW margin of the Tibetan Plateau. The modeling results indicate that the orogenic load of West Kunlun triggers the southern Tarim Basin to subside by up to less than ∼6 km, with its impact weakening towards the basin interiors until ∼230 km north from the Karakax fault. The sedimentary load, consisting of Cenozoic strata, forces the basin to subside by ∼2 to ∼7 km. In combination with the retreat of the proto‐Paratethys Sea and the paleogeographic reorganization of the Tarim Basin, we propose that surface processes, in particular a shift from an exorheic to an endorheic drainage system associated with the consequent thick sedimentary load, played a decisive role in forming deep intracontinental basins in the context of the India–Eurasia collision. [ABSTRACT FROM AUTHOR]

Extensional systems of back-arc basins have been widely recognized and studied in SE Asia, however the interactions between extensional tectonics and spatial-temporal distributions of tectonic subsidence in an active back-arc basin are poorly known. Using a backstripping technique, we analysed 33 multichannel seismic profiles to calculate the Neogene tectonic subsidence across the entire Okinawa Trough (OT) for the first time. Reconstruction of the tectonic subsidence shows that the OT can be roughly divided into four subsidence stages with variable rate. By comparing the temporal-spatial distribution of the intensive subsidence area, we confirmed that rifting events first occurred in the northern segment (NOT) and middle segment (MOT) from the Miocene to Late Pliocene, and then propagated to the southern segment (SOT) after the Late Pliocene. The factors controlling the rapid tectonic subsidence over the entire OT can be classified into two categories: 1) NE-to NNE-trending normal faulting, related to extension of the OT, and NW- to NWW-trending strike-slip faulting; i.e., the Tokara Fault and the Miyako Fault, related to subduction of the Philippine Sea Plate under the Eurasian Plate; 2) The anomalous rapid subsidence occurred in the southernmost part of the SOT is likely related to the subducted Gagua Ridge which caused magma intrusion resulting from partial melting. We suggest that magmatic bodies produced by partial melting of subducted materials intruded into the crust and created a dense lithosphere, causing this rapid tectonic subsidence. • The subsidence center first occurred in the NOT and MOT since Miocene, then propagated to the SOT after the Late Pliocene. • Rapid tectonic subsidence focuses on the NE-NEE-trending rifting center and the NW-NWW-trending strike slip faults. • Anomalous rapid subsidence in the center and southernmost part of the SOT was related with the subduction of Gagua Ridge. [ABSTRACT FROM AUTHOR]

Extensional systems of back-arc basins have been extensively recognized and studied especially in SE Asia. The Okinawa Trough (OT) represents a typical back-arc basin along the Western Pacific Margin, which experienced multi-episodic rifting events during the Cenozoic. This contribution aims to investigate the interactions between extension-related tectonics and spatial-temporal distributions of subsidence in this active back-arc basin. The OT is characterized by three segments (southern, middle and northern) exhibiting different geological characteristics emphasized by distinct crustal thickness, gravity anomaly, structural style, convergent rates and slap depths in the subduction zone. From its structural location, the OT provides an opportunity to study the initiation of rifting and subsequent back-arc spreading dominated by interaction between the Philippine Sea Plate and the Eurasian Plate. Meanwhile, its sedimentary history is complicated by southward propagating continental rifting, initial seafloor spreading in the southern segment, the Taiwan Orogeny, and widespread volcanic additions. All these elements resulted in the OT of remarkable differences in sedimentary facies, depositional environments and sedimentary processes in different areas. As result, we explored and compared the tectonic subsidence of its different segments, investigating the tectono-sedimentary processes and mechanisms controlling its evolution during different geological stages.In this presentation we use the one-dimensional backstripping method to investigate the temporal-spatial distribution of tectonic subsidence and sedimentary processes in the OT. Based on more than 30 multi-channel seismic profiles, we present a seismo-stratigraphic analysis and a precise framework with detailed geological interpretations. This study enables us to 1) reconstruct the tectonic subsidence during different geological stages, 2) replace the subsidence evolution in a tectonic context, 3) investigate the key factors controlling the sedimentary processes and the infill of different segments, and 4) provide the first detailed maps of decompacted sedimentary thickness and tectonic subsidence for the entire OT. Eventually, we will also explore the style of continental extension and the corresponding rapid subsidence patterns in the multi-episodic extension systems. [ABSTRACT FROM AUTHOR]