Palaeoenvironmental setting of the Kangdian area, southwest China, in Proterozoic Datian–Meidang time

AbstractNumerous acritarchs and stromatolites have been discovered and studied from the Proterozoic Datian Formation of the Kunyang Group and the Meidang Formation of the Dongchuan Group in Sichuan–Yunnan area, southwestern China, and more than 80 oxygen isotope data have been obtained from the sediments. Based on size-range and variation of non-filamentous acritarchs, the development of columnar stromatolites and the 18O/16O values of stromatolitic and nonstromatolitic carbonate rocks, the author proposes, for the first time, a palaeoenvironmental framework of the Kangdian area during Datian–Meidang time.Although the usefulness of Precambrian acritarchs and oxygen isotope values in palaeoenvironmental analysis of a sedimentary basin is just beginning to be understood, it is evident that these data are an important basis for palaeoenvironmental studies.