Fault-controlled carbonate-hosted barite-fluorite mineral systems: The Shuanghe deposit, Yangtze Block, South China

Fault-controlled carbonate-hosted Ba-F deposits occur in many major orogenic belts of the world and are important repositories of fluorine production required in various fields of chemical, metallurgical glass, ceramic, and cement industries. Here we investigate the poorly documented Shuanghe barite-fluorite deposit in the Yangtze Block of South China. This deposit offers an excellent case for studying the processes of formation of fault-controlled carbonate-hosted barite-fluorite mineral system. The orebodies in Shuanghe are hosted in carbonate rocks belonging to the early Ordovician Honghuayuan Formation and are dominantly controlled by NE-trending faults. Fluorite and barite exhibit similar rare earth element patterns with positive Eu anomalies and negative Ce anomalies. We report fluorite Sm-Nd isotopic data which yielded an isochron age of 103.1 +/- 1.3 Ma. The 818OV-SMOW values range from +0.2%x to +1.1%x and the 8DV-SMOW values show a range of -33.1%xto -26.3%x. The 834SV-CDT values for barite range from 31.1%x to 38.2%x. The bulk and in-situ Sr values for fluorite and barite show a range of 0.709081 to 0.712258. The petrological and geochemical data reported in this study suggest the following processes: (1) derivation of the ore-forming fluid from basinal water mixed with meteoric water; and (2) origin of the ore-forming components from Cambrian carbonate rocks, black shale, and Ordovician limestone. We propose a model that correlates the tectonic background of mineralisation with the Late Cretaceous subduction of the Paleo-Pacific Oceanic plate. (c) 2021 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Automated summary

This study investigates the poorly documented Shuanghe barite-fluorite deposit in the Yangtze Block of South China, providing an excellent case for studying the processes of formation of fault-controlled carbonate-hosted barite-fluorite mineral system. The ore-forming fluid is derived from basinal water mixed with meteoric water, and the ore-forming components mainly come from Cambrian carbonate rocks, black shale, and Ordovician limestone. The tectonic background of mineralisation is correlated with the Late Cretaceous subduction of the Paleo-Pacific Oceanic plate.