According to Li (2017), strike-slip faults existed in two phases of development, at the end of the Sinian and the end of the Early Cambrian. (2013) suggested that deep fault systems formed during the Caledonian tectonic period, and experienced multiple stages of strike-slip fault activity in the Hercynian, Indosinian, Yanshan, and Himalayan epochs. Currently, there is consensus on the development of deep strike-slip faults in the central area of the Sichuan Basin, but there are still controversies regarding the distribution pattern, nature, and formation period of said faults. Influenced by the traditional concept of the stable central Sichuan block, previous studies on the deep fault system of the central Sichuan Basin remain incomplete. Previous studies in this region have focused on tectonic evolution, sedimentary facies distribution, and hydrocarbon migration and accumulation. Since 2006, with the discovery of the Anyue gas field, the Gao Shi 1 and Moxi 8 wells in the central Sichuan area have been drilled and tested to obtain a high-yielding industrial gas flow from the Sinian-Cambrian dolomite reservoir, confirming the huge exploration potential of deeper layers in central Sichuan. Faults and concomitant joints accompanying the multi-stage tectonic evolution could both act as passageways for oil, gas, hydrothermal, and volcanic fluids, as well as playing an important role in later reservoir transformations and hydrocarbon accumulation. Most marine carbonates in China are formed in the lower part of the superimposed basin, characterized by deep burial and ancient origin, and have undergone complex diagenesis along with multi-phase tectonic movements during its geological history. Recently, carbonate oil and gas exploration has gradually moved into deep (burial depth >4500 m) and ultra-deep (>6,000 m) carbonates with increasing progress in exploration technology, resulting in new discoveries of various oil and gas resources ( Liu et al., 2009 Li et al., 2020 He et al., 2021 Liu et al.,2010). Dedicated research in China has led to globally recognized discoveries in the marine carbonate formations of the Tarim, Sichuan, and Ordos Basins. Global carbonate formations are rich in hydrocarbon resources, and will likely be the most important area for future oil and gas exploration and development. Strike-slip faults are important hydrocarbon migration paths, and their multistage activities have different controlling effects on hydrocarbon accumulation. Reservoirs of the hard-linked zone of the strike-slip fault are the most developed, followed by those of soft-linked segments, with translational sections of the strike-slip fault being relatively undeveloped. The segmentation of strike-slip faults strongly controls the quality of fractured vuggy reservoirs. The faults showed features of layered deformation and staged evolution in the vertical direction. The results showed that the deep strike-slip fault system, mostly distributed in the Dengying Formation, can be divided into four stages, three levels, and three groups of orientation, which controlled the structural framework and shape of the central Sichuan area, as well as the zoning from north to south, and blocking from west to east. Using a comprehensive analysis technique to assess the strike-slip fault tectonic activity history, the formation and evolution processes of strike-slip faults and their control on hydrocarbon distribution were examined. In this study, the spectral decomposition coherence method was used to describe the geometric and kinematic characteristics of these strike-slip faults. Previous studies have suggested a developed series of high-angle strike-slip fault systems in the central Sichuan Basin, but correlated exploration activities are limited, as distribution rules and dynamic mechanisms remain unclear. Deep faults research has also attracted increasing attention, as faulting plays an important role in reservoir control. The past decade has witnessed a breakthrough in the gas exploration of deep marine carbonates of the central Sichuan Basin.
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