A study on the Manganese-Bearing fluid Diapir–Discharge structural system of the Datangpo-Type manganese deposits in China

The Datangpo-type manganese deposits in China represent a distinct category of manganese deposits, i.e., sedimentary exhalative manganese deposits. These deposits, distributed predominantly across secondary grabens in the Wuling secondary rift within the Neoproterozoic Nanhua Rift, are characterized by a manganese-bearing fluid diapir–discharge structural system. Field observations identified four structural types within these deposits from the base upward: domal ridges, mud diapir columns, dendritic jet-flow tubes, and fan-shaped upwelling lineations. These interconnected structures form a complete shallow-level diapir–discharge system. Detailed studies of the structural morphology, material composition, and kinematic and dynamic features revealed that the source of the manganese is predominantly deep-seated manganese-bearing fluids. Multiple stages of fluid diapirs and discharges have produced several sets of diapir–discharge systems, which might occur across different stratigraphic horizons or overlap and transform within the same horizon. Identification of such fluid diapir–discharge systems is critical for understanding the metallogenic mechanisms of Datangpo-type manganese deposits in China.