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Despite extensive efforts to understand the tectonic evolution of the Jiangnan Orogen in South China, the orogenic process and its mechanism remain a matter of dispute. Previous geodynamic studies have mostly focused on collisional orogeny, which is commonly invoked to explain the Jiangnan Orogen. However, it is difficult for such hypotheses to reconcile all the geological and geophysical data, especially the absence of ultrahigh‐pressure metamorphic rocks. Based on the magnetotelluric data, we present a group of resistivity models produced through the combination of two ‐dimensional and three‐dimensional inversions, revealing the geo‐electrical structures of Jiangnan and a typical collisional orogen. In our models, the resistive crust is separated into three parts by a prominent conductive layer with opposite dipping directions on both sides. A special thrust‐nappe system, which is different from that developed in a typical collisional process, is revealed in the Jiangnan Orogen. This structure suggests a process different from the simple collisional orogeny. To interpret our observations, an 'intra‐continental orogeny' is proposed to address the development of the Jiangnan Orogen in the Mesozoic. Furthermore, this 'reworked' process may contain at least two stages caused by the decoupling of the lithosphere, which is revealed by an extra conductive layer beneath Jiangnan. [ABSTRACT FROM AUTHOR]

The northern Wuyi area, which is located in the northern Wuyi metallogenic belt, has superior mineralization conditions. The Pingxiang–Guangfeng–Jiangshan–Shaoxing fault (PSF) extends across the whole region regardless of whether or how the PSF relates to the near‐surface mineralization. We carried out an MT survey in the region and obtained a reliable 2D model of the crustal electrical structure to a depth of 30 km. In the resistivity model, we inferred that a continuous high conductivity belt that ranges from the shallow to deep crust is a part of the PSF. Then, we estimated the fluid content and pressure gradient to identify the deep sources of fluid as well as its pattern of motion pattern. Finally, we proposed a model for the deep metallogenic migration processes that combines geological data, fluid content data, pressure gradient data, and the subsurface resistivity model. The model analysis showed that the Jiangnan orogenic belt and the Cathaysia block formed the PSF during the process of com. The deep fluid migrated upward through the PSF to the shallow crust. Therefore, we believe that the PSF is an ore‐forming fluid migration channel and that it laid the material basis for large‐scale mineralization in the shallow crust. [ABSTRACT FROM AUTHOR]

The Zhuxi tungsten deposit in Jiangxi Province, South China, contains a total W reserve of about 2.86 Mt at an average grade of 0.54 wt% WO3, representing the largest W deposit in the world. Numerous studies on the metallogeny of the deposit have included its timing, the ore‐controlling structures and sedimentary host rocks and their implications for mineral exploration. However, the deep nappe structural style of Taqian–Fuchun metallogenic belt that hosts the W deposit, and the spatial shape and scale of deeply concealed intrusions and their sedimentary host rocks are still poorly defined, which seriously restricts the discovery of new deposits at depth and in surrounding areas of the W deposit. Modern 3D geological modeling is an important tool for the exploration of concealed orebodies, especially in brownfield environments. There are obvious density contrast and weak magnetic contrast in the ore‐controlling strata and granite at the periphery of the deposit, which lays a physical foundation for solving the 3D spatial problems of the ore‐controlling geological body in the deep part of the study area through gravity and magnetic modeling. Gravity data (1:50000) and aeromagnetic data (1:50000) from the latest geophysical surveys of 2016–2018 have been used, firstly, to carry out a potential field separation to obtain residual anomalies for gravity and magnetic interactive inversion. Then, on the basis of the analysis of the relationship between physical properties and lithology, under the constraints of surface geology and borehole data, human–computer interactive gravity and magnetic inversion for 18 cross‐sections were completed. Finally, the 3D geological model of the Zhuxi tungsten deposit and its periphery have been established through these 18 sections, and the spatial shape of the intrusions and strata with a depth of 5 km underground were obtained, initially realizing "transparency" for ore‐controlling bodies. According the analysis of the geophysical, geochemical, and geological characteristics of the Zhuxi tungsten deposit, we discern three principles for prospecting and prediction in the research area, and propose five new exploration targets in its periphery. [ABSTRACT FROM AUTHOR]

The article discusses research which analyzed the gravity and magnetic evidence for the geological setting of major mineral systems of the main metallogenic belts in South China. Topics covered include the metallogenic factors of the deposits, the difference in the type and metal association of the deposits, and the distribution of termination sites of different mineral systems in the area which provide indications for future ore-prospecting exploration in South China.