Structural and geochemical constraints on the genesis of the Kuangshanchang carbonate-hosted zinc-lead deposit, Huize district, southwestern Yangtze Craton

The southwestern Yangtze Craton hosts over 400 carbonate-hosted zinc-lead deposits that are mostly subjected to regional folding and thrusting; however, the structural controls are poorly understood, and genesis of the deposits also remains controversial. The Kuangshanchang zinc-lead deposit (Zn + Pb: 4 Mt @ 25%) provides a typical example to unravel the issues. We herein present new structural and geochemical data from field investigation and structural mapping at Kuangshanchang. The deformational history was reconstructed by structural mapping and 158 sets of data, including NW-directed thrust faults (D1-1), NW-striking sinistral and normal faults (D1-2), and N-S-striking dextral faults (D-2). Whole-rock geochemical analysis from 20 samples yields high anomalies of the ore-forming elements (Zn, Pb, Ag, Ge, Ga, and Cd) within the D1-2-stage NW-striking faults, highlighting its pivotal ore-controlling role. In situ LA-ICP-MS microanalysis from 12 samples shows that Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ge, As, Se, Ag, Sb, and Pb is enriched in pyrite. Low Co and Ni abundances (0.01 x 10(-6)-20.99 x 10(-6)) and Co/Ni ratios (0.01-2.35) constrain a low-temperature hydrothermal origin for pyrite. New field, structural, and geochemical data, integrated with previous studies, allow for a genetic model coinciding with MVT deposits. We suggest the D1-2-stage NW-striking high-angle extensional faults and the NE-striking interlayer fractures jointly determine the localization of the orebodies at the deposit scale. Our research enhances the understanding on the genesis of the zinc-lead deposits in the southwestern Yangtze Craton and provides guidelines for regional and deposit-scale prospecting.