Besides, the pronounced negative δ13Ccard shift that can be correlated with the Shuram excursion has beenreported from the middle Ediacaran in the Yangtze Gorges area of South China. Whether it represents a truerecord of the ocean carbon cycle at the time of sedimentation or the post-depositional alteration is still open todebate, while the latter explanation refutes the reliable application of the carbon isotope record forchemostratigraphic correlation of Ediacaran successions.