Hydrothermal-reworked sedimentary diagenetic lead-zinc deposit, hosted in carbonatites. The Maoping Pb–Zn carbonate-hosted deposit in the Sichuan–Yunnan–Guizhou lead–zinc polymetallic mineralization area has ~14 Mt of sulfide ores at mean grades of 6.1 wt.% Pb and 20.2 wt.% Zn.

The Maoping deposit is one of largest Pb-Zn deposit in the SYG area and hosts 12.51 Mt ores with average Pb + Zn grades of 20.3%, as well as existing 560 t Ag metals of 75 g/t grade and 182 t Ge metals with an average grade of 24 g/t. Bounded by the NW-trending Luoze river, the eastern I-III ore belt and the western Shuilu, Qiancengdong and Hongjianshan ore belts constitute principal part of the Maoping Pb-Zn deposit. The exposed strata in the Maoping deposit are composed of the Devonian Zaige Formation, the Carboniferous Datang, Baizuo and Weining Formations, the Permian Liangshan and Qixia-Maokou Formations, together with the Permian Emeishan basalts and Quaternary sediments.

The eastern part comprises the Nos. I, II, and III ore blocks, which are crucial components and account for more than 80 % of the total resources. The No. 1 section comprises dolomite interbedded with thin layers of carbonaceous shale, and the No. 2 section contains algae-bearing dolomite accompanied by a limited amount of shales, carbonaceous shales, and crystalline limestones. The No. 3 section is composed of coarse-grained dolomites interspersed with stratified carbonaceous shales. The ore grades increase gradually from top to bottom, accompanied by a decrease in Zn content but an increase in Pb content. The Pb–Zn orebodies in Maoping exhibit significant vertical extension (>1200 m) along nearly vertical interlayer faults, indicating that the ore–forming fluids were transported through these interbedded faults and effectively mixed with fluids containing reducing sulfur.

The Devonian Zaige Formation, the Carboniferous Datang, Baizuo, and Weining Formations, and the Permian Liangshan and Qixia-Maokou Formations are exposed in the Maoping deposit. Three distinct hydrothermal stages: (1) dolomite-pyrite veins, (2) sphalerite-galena veins, and (3) calcite veins.

The Maoping Pb-Zn deposit is predominantly characterized by the NW-trending Luozehe Fault and NE-trending Maoping Fault. The key ore-controlling fold structure within the Maoping area is the Maomaoshan overturned anticline, situated on the hanging wall of the NE-trending Maoping Fault. The nucleus of anticline consists of dolomites from the Zaige Formation, while the limbs are composed of sandstones and shales from the Datang Formation and carbonate rocks from the Bazuo Formation. There are six significant ore body groups that have been discovered in the Maoping Pb-Zn deposit. The main mineralized sections are identified as ore bodies I, II, and III, which primarily occur as vein-like and lenticular forms within marine carbonate rocks. Ore body I trends SE–NW, as the principal ore body in the deposit, extends over 600 m in length, and has a thickness ranging from several meters to over 30 m. It predominantly dips southeastward, with a steep inclination of approximately 85°. The Zn grade ranges from 3.9% to 30.9% (mean 12.8%), while the Pb grade varies between 2.64% and 13% (mean 5.46%). Additionally, the Maoping deposit is associated with Ag and Ge, including 560 t Ag metals, with an average grade of 75 ppm, and 182 t Ge metals, with an average of 24 ppm. Integrating the geological and geochemical characteristics of the deposit, it can be concluded that the Maoping deposit should be classified as a unique Sichuan–Yunnan–Guizhou Pb-Zn metallogenic belt Pb-Zn deposit.

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