|Abstract:To reveal the deep structure and occurrence-development process of the Yishu Fault Zone (YSFZ), and find out the cutting depth of the fault and the damage to the lithospheric mantle, and explore interpretation of the YSFZ tectonic combination style, exercise, crustal stability and its constraints on resources and environment, in 2019, a deep reflection seismic profile about 60 km long was set up near Yinan-Juxian in the southern segment of the YSFZ to dissect the fine structure of the lithosphere of the YSFZ and the blocks on both sides, the seismic data are systematically collected. The results show that the lithospheric structure of this area is laterally characterized by a massive structure bounded by the YSFZ; the crustal thickness of this area is about 30.8~39.5km. The Moho surface is generally shallow in the west and deep in the east, and it is broken by the Yishui-Tangtou fault (F2) and Changyi-Dadian fault (F4) that lean to the west, with a vertical drop of 10.5km. Different from the shallow structural combination pattern of "two grabens sandwiched with one horst", the YSFZ appears as a "double branched" structural combination pattern consisting of multiple faults extending upward and bifurcating from Yishui-Tangtou fault (F2) and Changyi-Dadian fault (F4) on the section. The reflected waves of the interface cut by the fault are mostly upward arcs, and the structural traces have the characteristics of extension, compression and strike-slip. It is inferred that these interfaces are interlayer slip structures, which indicate the "multi-layer slip" tectonic movement mode in the YSFZ. The YSFZ cuts the geological interface near the surface and the inner crust. The F2 and F4 faults cut the Moho surface downwards and penetrate into the lithospheric mantle. The YSFZ is a deep faulted structural zone reaching the mantle and provides a channel for the upwelling of hot mantle materials and controlling the Mesozoic magmatism and endogenetic mineralization. The mineralization of Tongjing gold deposit at the western end of the seismic section is closely related to the Tongjing complex intrusion along the F2 fault; the volcanic structure at the eastern end of the profile is well preserved without obvious traces of structural damage. Therefore, it is considered that the left lateral strike slip of the YSFZ occurred mainly before the early Cretaceous Qingshan period, and the post horizontal slip should be small. According to the regional geological distribution and seismic inversion results, Changyi-Dadian fault (F4) obviously divides Shandong Province into two geological structural units, i.e. West Shandong and East Shandong. Therefore, it is reasonable to take it as the boundary of regional geological structure. The results of this study further deepen the understanding of the deep and shallow structure of the YSFZ, and provide data constraints for the analysis and study of the deep process and shallow structure response of the YSFZ and its impact on the resource environment.