Early Cretaceous provenance-depositional systems and volcano-sedimentary responses to strike-slip faulting in southern Jilin and eastern Liaoning provinces, NE China: a case study of the Tonghua Basin

Understanding how the sedimentary responses adapt to the structural styles of fault basins in the strike-slip fault systems is one of the key goals of basin analysis. Variability of volcanic and epiclastic provenance-depositional systems and tectonic controls of the Lower Cretaceous Hengtongshan Formation in the Tonghua Basin are crucial to determine the evolution of the fault basins and wrench tectonics in southern Jilin and eastern Liaoning provinces (SJELP), NE China. Study of volcanism-induced sedimentation, composition plot, and depositional systems elucidates the sequence stratigraphy and volcano-sedimentary responses to wrench tectonics based on cores, outcrop sections, and seismic profiles of the Tonghua Basin. Two types of provenance-depositional systems (volcanic and epiclastic) were reconstituted using eight lithofacies and seven lithofacies associations. Of the lithofacies, six pyroclastic lithofacies and two epiclastic lithofacies were identified based on compositions, textures, and sedimentary structures. The presence of these lithofacies in different vertical successions was described as different lithofacies associations to interpret depositional processes and sedimentary environments. Depositional-system maps of the three sequences in the Hengtongshan Formation and analysis of structural framework indicate that volcanism and sedimentation were controlled by wrench faulting. Statistical analysis of rock compositions reveals that the deposition of the Hengtongshan Formation shows mixed contribution from both the volcanic and granitic fragments. Triangular compositional plots of detrital composition suggest a diverse provenance by straddling the litho-feldspatho-quartzose (lFQ), feldspatho-litho-quartzose (fLQ), feldspatho-quartzo-lithic (fQL), and quartzo-feldspatho-lithic (qFL) fields, indicating that the sources were derived from uplifted basement blocks and volcanic eruptions in a rift basin related to strike-slip faulting. The Tonghua Basin developed as a wrench-fault basin on the east side of Dunhua-Mishan Fault systems (DMF). This model for the Tonghua Basin can be used to understand the Liuhe Basin in the DMF and other Early Cretaceous basins in adjacent areas.