Features of Jiama(Gyama)-Kajunguo Thrust-gliding Nappe Tectonic System in Tibet
西藏甲玛-卡军果推-滑覆构造系特征

Based on reconnaissance survey and geological mapping as well as comprehensive literature review and laboratory study, this paper presents the following conclusions: Firstly, the Jiama-Kajunguo thrust-gliding nappe tectonic system, which resulted from the Indo-Asia collision, deformed successively from the central part of the basin toward the margin, the new layer overlay the old one, and the greatest deformation occurred around 50 Ma±. Secondly, the footwall block of the nappe is the Yeba group tectonite, the nappe consists of the upper Jurassic and lower Cretaceous carbonate and siliciclastics, the main part that is a complex fold with axial plane trends northward and can be divided into the fore-, mid- and post-parts from south to north structurally. The rock mass was located in the gliding nappe system at the top of the anticlinorium axis due to gravitational disequilibrium, which caused the hanging-wall block overlying the nappe to slip toward the north; the gliding nappe system is also divided into the fore-, mid- and post- parts from the south to the north in this paper. At last, the magmatic activities that induced the ore-forming alteration of the Jiama(Gyama) deposit happened during the releasing stage after the contraction stage of the thrust-gliding nappe tectonic system, and the upward migration of the magma was collaboratively controlled by the NS-trending basement faults and the thrusts. The magmatic rock that was emplaced finally in the fore-part of the thrust-gliding nappe tectonic system experienced multiple structural-magmatic-mineralization superimposition and generated the superlarge Jiama(Gyama) Cu polymetallic deposit.