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Mineralogical and Geochemical Constraints on the Ore-Forming Processes of the Datangpo Manganese Deposits in Western and Central Hunan, South China

Year: 2026

Type: article

Abstract: Datangpo-type manganese (Mn) deposits in South China constitute a key archive of Cryogenian postglacial oceanic evolution and large-scale Mn mineralization. However, systematic comparisons between western and central Hunan remain limited, particularly regarding redox conditions, Mn precipitation pathways, and Mn sources. This study investigates Mn ores hosted within the Datangpo black shale succession in western and central Hunan through integrated petrographic, mineralogical, and whole-rock geochemical analyses. The ores are dominated by rhodochrosite and dolomite, with subordinate quartz, pyrite, and illite. Pyrite framboid characteristics together with redox-sensitive trace element systematics record increasingly reducing conditions from high- to low-grade ores, highlighting the control of redox conditions on Mn enrichment. Medium- to high-grade ores show limited terrigenous input and generally shift toward hydrothermal Fe–Mn end members, consistent with a hydrothermal contribution to Mn supply. Mn enrichment generally involved oxidative fixation during deposition, followed by reductive carbonatization during early diagenesis. Locally intensified hydrothermal input may also have promoted limited direct precipitation of Mn carbonate under reducing, Mn-rich, and alkaline conditions. This model may provide a useful basis for interpreting other Datangpo-type Mn deposits in South China.

Source: Applied Sciences

DOI: 10.3390/app16178590