Acanthomorphic acritarchs of the Doushantuo Formation from an upper slope section in northwestern Hunan Province, South China, with implications for early–middle Ediacaran biostratigraphy

Abstract

Doushantuo-Pertatataka acritarchs (DPAs) are abundant and well preserved in the Ediacaran Doushantuo Formation in South China. Not only do they provide insights into the marine ecosystem immediately after a Neoproterozoic global glaciation, they also afford us an ideal tool for Ediacaran stratigraphic subdivision and correlation. However, previous reports of DPAs in South China are mostly from the Yangtze Gorges area in intra-shelf basin and from Weng’an in shelf margin environments, while data from localities in slope and basinal facies are lacking. Here we present lithostratigraphy, carbon and strontium isotope chemostratigraphy, and acritarch biostratigraphy of the Doushantuo Formation from an upper slope section at Lujiayuanzi in northwestern Hunan Province, South China. Five DPA genera and eight species are preserved in the Doushantuo Formation chert nodules, with the uppermost two DPA horizons occurring above a δ13C negative excursion that is correlated with the EN3/Shuram excursion based on integrated litho- and chemostratigraphic correlation. Our new findings reveal a broader temporal and spatial distribution of DPAs in South China, and further support their biostratigraphic potential in the early–middle Ediacaran subdivision and correlation.