There are very close relationships between orogenic belts and their peripheral sedimentary basins: they are spatially interdependent in structure, mutually compensatory in material, interactive in tectonics, simultaneous in tectonic evolution. The relationships indicate a unified formation mechanism for the continental orogenic belts and the sedimentary basins, which can be presented as follows: lower crustal ductile lateral flow from the basin to the orogen, driven by thermal energy related to upwelling mantle plume in the intracontinental crust and by vertical diaper movement of dehydration and magma of the subduction plate on the active continental margin, results in the circulative movement of crust materials between basins and orogens. The coupling between the Qinghai–Tibet Plateau and its peripheral basins is a typical basin-orogen coupling occurring in the intraplate tectonic setting. The formation of the Qinghai–Tibet Plateau is not a result of collision between the India plate and the Eurasia plate, but rather the result of intraplate basin-orogen formation process driven by lower crustal flow. The tectonic evolution of intraplate basin-orogen system in the Qinghai–Tibet Plateau can be divided into two stages: (1) intraplate orogen-basin formation stage. During this stage, the spatial and temporal evolution of the intraplate orogens and basins in the Qinghai–Tibet Plateau is indicated by the successive geographic movement of the locations of the new basin-orogen systems from the northern and eastern, to the central, and finally to the southern Qinghai–Tibet Plateau, corresponding geochronologically to periods from 180–120 Ma, to 65–30 Ma, and finally to 23–7 Ma. This stage was manifested by extensive intraplate faulting, folding, block movement, magmatism and metallogeny. (2) isostatic mountain building and basin margin subsidence stage. In this stage, there were rapid uplift and strong erosion of the entire Qinghai–Tibet Plateau and rapid subsidence and molasse formation in the depressions on the margins of the peripheral basins resulted from gravity isostasy since 3.6 Ma. The stage is characterized by pulsative uplift and subsidence, crust-scale vertical movement, integral rapid uplifting of the Plateau, local subsiding of basin margin, and tremendous change in topography and environment, with pulses at 3.6 Ma B.P., 2.5 Ma B.P., 1.8–1.2 Ma B.P., 0.8 Ma B.P., 0.15 Ma B.P., etc. The intracontinental basin-orogen systems also underwent tectonic transformation from extension to compression, and the active movement respectively changed from the basin to the orogen. Non-Anderson low-angle detachment, wavy thrust faults, and abnormal conjugate strike-slip faults are formed due to lower crustal flow and intraplate basin-orogeny coupling.
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