Abstract: The phosphorites in Weng’an,Guizhou are hosted in the lower and upper parts of the Doushantuo Formation,and made up of carbonate rock-type phosphatic rock series on a shallow marine carbonate platform.The strata of the Doushantuo Formation deposited after the Marinoan glacial period may be grouped into six shallowing-upward depositional sequences.The bulk of phosphatic rock series is built up of polycyclic stacking deposits in which cross-bedding,wavy bedding and lenticular bedding are common,implying that the phosphorites rested in the shallow marine high-energy environments.From the Nantuoan glacial period onwards,the large-scale transgressions gave rise to the upwelling oceanic currents and carried plentiful phosphatic sea water into the shallow marine areas as sites of phosphorites development.The repeated sea-level fluctuations contributed to the phosphatic source and development of polycyclic depositional sequences of the phosphorites.