Metallogenic model of the Hongqiling Cu–Ni sulfide intrusions, Central Asian Orogenic Belt: Insight from long-period magnetotellurics

Abstract

The Hongqiling magmatic Cu–Ni sulfide deposit is one of the most important deposits in the easternmost segment of the Central Asian Metallogenic Belt, northeast China. However, the existence or non-existence of magmatic chambers is still not been determined, which is the key to decipher the formation of Hongqiling Cu–Ni deposit. Therefore, this study proposes to adopt long-period magnetotellurics method to image the deep-seated metallogenic system in Hongqiling Cu–Ni deposit. Two-dimensional (2D) nonlinear conjugate gradient inversion technology allows us to describe entire magma plumbing system, including the mantle-derived magma channels (banded low-resistivity anomalies), deep separated chamber (low-resistivity anomaly C2), and shallow magma conduits (low-resistivity anomaly C1). These results indicated that the mantle-derived primitive magma gave rise to the parental magma for the mafic–ultramafic intrusions in Hongqiling Cu–Ni deposit and triggered the segregation of Cu–Ni sulfides in the shallow chamber. By combining the experimental simulation, geochemistry, geochronology, and geotectonics data in the study area, we suggest that the partial melting processes which produced the large magma plumbing system probably have been triggered by lithospheric delamination.

Assessment of geothermal resource potential in Changbaishan utilizing high-precision gravity-based man-machine interactive inversion technology

“…Corrections for Free-air and Bouguer anomalies were done using the International Association of Geodesy (1971) 1,967 formula considering 2.67 g/cm 3 as the density of the middle layer (Morelli et al, 1972;Sundaralingam, 1987;Luo and Yao, 2007;Xu et al, 2022a). Corrections for the gravimetric terrain in near (0-20 m), intermediate (20-2,000 m) and remote areas (2-20 km) were performed using the Trupulse 200 type laser height instrument monitoring data, 1:10,000 scale elevation database and 1:50,000 scale elevation database, respectively.…”

“…Corrections for the gravimetric terrain in near (0–20 m), intermediate (20–2,000 m) and remote areas (2–20 km) were performed using the Trupulse 200 type laser height instrument monitoring data, 1:10,000 scale elevation database and 1:50,000 scale elevation database, respectively. Finally, based on cone-shaped column formula, the topographic correction value of each gravity points are calculated (Laramie and Ralph, 2003 ; Xu et al, 2022a ). The theoretical formula is listed as follows.…”

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

“…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...…”