Crustal Electrical Structure and Deep Metallogenic Potential in Northern Wuyi Area (South China), based on Magnetotelluric Data

• Published in: Acta geologica Sinica (Beijing) 2022-06, Vol.96 (3), p.791-805
• Main Authors: LUO, Fan, LÜ, Qingtian, ZHANG, Kun, YAN, Jiayong, FARQUHARSON, Colin G., ZHANG, Chong, FU, Guangming
• Format: Article
• Language: English
• Subjects: Belts; crustal electrical structure; deep metallogenic background model; Electrical resistivity; Geological data; magnetotellurics; Metallogenesis; Mineral deposits; Mineralization; northern Wuyi area; Orogeny; Pressure gradients; PSF; Surveying; Two dimensional models
• ISSN: 1000-9515; 1755-6724
• DOI: 10.1111/1755-6724.14864

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.