The Influence of the Ailaoshan‐Red River Shear Zone on the Mineralization of the Beiya Deposit on the Southeastern Margin of the Tibetan Plateau Revealed by a 3‐D Magnetotelluric Survey

Abstract

The Jinshajiang-Ailaoshan alkaline porphyry Cu, Mu, and Au polymetallic belt is an important Cenozoic metallogenic belt in SW China which extends for over 1,000 km (Figure 1a; W. C. . It is adjacent to the intra-continental Jinshajiang-Red River strike-slip fault system of the Tethys-Himalaya orogenic belt. This belt hosts dozens of economically significant porphyry and skarn ore deposits that are related to potassic porphyritic intrusions (Hou et al., 2017). It is believed to be the result of the long-term interaction between the Indochina and the Yangtze craton and the lateral extrusion of the Indochina block during the continental collisional process of the Tibet and the Indian block (Deng et al., 2015).

A Review of Relationship between the Metallogenic System of Metallic Mineral Deposits and Lithospheric Electrical Structure: Insight from Magnetotelluric Imaging

“…Therefore, the fractures and fault zones in the rocks not only act as important migration channels of the medium, but are also filled with minerals as a vessel during mineralization. Generally, fractures and fault zones are indicated as zones of conduction from the subsurface to the deepseated zone, or electrical gradient belts between the conductive zones and resistive zones, or electrical interval belts between the resistive zones [45,46].…”

“…In this process, fluids are released and migrate to the low-pressure zone above. Following current mineralization, the late tectonic-magmatic events may reactivate the existing weakened zones and fault zones in the lithosphere, which can facilitate the migration and gathering of magmatichydrothermal materials [46]. During the mineralization of magmatic-hydrothermal deposits, the volatiles (e.g., chlorine, sulfur, carbon dioxide, methane, water) in the magmatic-hydrothermal materials also play an essential role in the mineralization of different deposits [5,[50][51][52][53].…”

“…The multi-scale electrical structure indicates a giant upper-mantle basaltic magma reservoir, indicated by the conductor DTHCZ beneath the Datong volcanic area, which moves through a lithosphere-scale shear zone, the mid-lower crustal magma chamber CZ3, the crust-scale weak zone, and a conduit (CC1 and CC2) to transport ore-forming magmas and fluids (Figure 7). Other typical results include the Ning (Nanjing)-Wu (Wuhu) basin in eastern China [90], the Shihu-Xishimen gold-iron ore district in North China [91], the Middle-lower Yangtze Metallogenic Belt (including Ningwu, Luzong, Xuancheng, Anqing, Guichi, and Tongling areas) in East China [12,[92][93][94][95][96], the Jiaodong gold deposits in northern China [97], the Liaodong Qingchengzi orefield [98], the Yixingzhai gold deposits (Boqiang Cu-Mo-Au deposits and Nanling W-Sn ore district in China) [45,99,100], the northeastern Jiangxi metallogenic province in southeastern China [101], the Caosiyao porphyry Mo ore district in North China [43], the Beiya Cu ore district in southwestern China [46], the large-scale Hatu epithermal gold deposit in western Junggar, NW China [102], Zhaxikang in the Tethys-Himalaya area in southwestern China [103,104], the Baogutu porphyry copper-gold deposit, the Hongqiling Cu-Ni sulfide intrusions in the Central Asian Orogenic Belt [105], the Xiangshan volcanogenic uranium deposit [106,107], the Narusongduo Pb-Zn-Fe-Cu ore district, and the Qulong-Jima porphyry ore Cu deposit in southwestern China [41,42]. In the Olympic Dam mine and Tennant ore district in Australia [108], the Tsagaan Tsahir Uul Au deposit in southern Mongolia [109], the Norrbotten district in northern Sweden [110,111], and the orogenic gold district in the Red Lake greenstone belt, western Superior craton, Canada [51], the electrical resistivity models obt...…”

Natural source electromagnetic survey for geothermal application in industrial area with strong electromagnetic noise

“…The magnetotelluric method (MT) (Avdeev, 2005) utilizes natural electromagnetic (EM) sources to image underground resistivity distribution (Guo et al, 2022;Li et al, 2023b). It has been widely used for underground structure imaging for different purposes (Yang et al, 2021a;Egbert et al, 2022;Yu et al, 2022;Wang et al, 2024). However, it can be easily affected by various EM noise generated by human activities (such as highvoltage power lines, trains, etc.…”

Crustal Electrical Structure of the Ganzi Fault on the Eastern Tibetan Plateau: Implications for the Role of Fluids in Earthquakes

“…In addition, where transects are collected, it is now becoming more common to use 3D inversion codes to perform inversions to achieve 3D representations of the data [34,36,37]. In recent years, MT soundings carried out on the eastern edge of the Tibetan Plateau have found widely distributed low-resistance layers in the middle and lower crust [38][39][40], which are considered to be the electrical reflection of the material flow [37,[41][42][43][44][45][46]. The MT results in these seismically active areas not only reveal the previously hidden seismogenic structure, but also show that the occurrence of moderate to strong earthquakes is closely related to the subsurface electrical structure of the active faults.…”