The Middle-Upper Ordovician succession in the Tarim Basin documents the evolution of a “reactivated cratonic basin” during the transition from a passive to a collisional continental margin. Deep exploration is hindered by extreme burial depths, limited seismic resolution, and unclear tectonic-sedimentary coupling mechanisms. This study integrates outcrops, cores, well logs, seismic data, and geochemical analyses to establish a high-resolution sequence stratigraphic framework, reconstruct the provenance evolution history, and decipher the spatio-temporal migration of sedimentary systems. Five third-order sequences (SQ1–SQ5) were identified: SQ1—upper Yijianfang and Qiaerbake Formations; SQ2—Lianglitage and lower Sangtamu Formations; SQ3–SQ5—middle–upper Sangtamu Formation. Provenance evolution exhibits a clear tectonically controlled three-stage pattern: during SQ1–SQ2, extra-basinal sources dominated, primarily from the Altyn Orogenic Belt, driven by its east-west “scissor-like” oblique collision; SQ3 was a mixed-source stage with contributions from both the Altyn Orogenic Belt and the Tazhong and Tabei paleo-uplifts, responding to intensified arc-continent collision and intra-basinal tectonic activation; SQ4–SQ5 transitioned to intra-basinal source dominance. The evolution of sedimentary systems was jointly controlled by the coupling of extra-basinal and intra-basinal tectonic dynamics, tectonically driven provenance migration, and relative sea-level fluctuations, overall showing a transition from deep-water gravity flow systems to shallow-water deltaic systems: (1) SQ1–SQ2 featured eastern submarine fans and western carbonate platforms; (2) SQ3 saw expanded eastern submarine fans and newly developed western slope turbidite fans; (3) SQ4–SQ5 were dominated by a basin-center “shelf to shelf-edge delta” system, with gradual shrinkage of the eastern deep-water fans. This study clarifies the core coupling mechanism of “tectonic activation driving provenance transformation, which in turn controls sequence distribution and sedimentary migration,” and establishes a “reactivated cratonic basin” sedimentary evolution model applicable to the Tarim type. The research results provide an important reference for the tectonic-sedimentary analysis of intracratonic collisional basins globally.
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