Sedimentary environments and exploration prospects of the manganesebearing strata in the Triassic Bocigou Formation in the Heishui-Pingwu region, western Sichuan

The Heishui-Pingwu region in western Sichuan is located in the Songpan marginal sea manganese-bearing basin as one of the key iron-manganese metallogenic zones in Sichuan on the northwestern margin of the Yangtze landmass, where a number of large-to medium-sized manganese deposits are hosted in the Triassic Bocigou Formation. The Bocigou Formation consists of clastic rocks and carbonate rocks and the manganese ores tend to be hosted in the transitional parts of calcareous rocks and clastic rocks. The shelf-shallow sea and submarine depressions are interpreted as the favourable environments for the deposition of manganese ores. The frequent evolution of sedimentary facies are considered as important prospecting criteria in the field. The Xiakou district in Heishui and Huya district in Pingwu are delineated as the exploration targets of manganese deposits.