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The Ediacaran Doushantuo Formation (dating from 635 Ma to 551 Ma) of South China is composed of alternating siliciclastic and carbonate units and yields abundant extraordinarily preserved animal embryos, macroscopic multicellular algae and Ediacara-type fossils. Thus, it is critical for the chronostratigraphic calibration of the Ediacaran Period and for deciphering the evolutionary history of life during this time interval. In order to establish a high-resolution Ediacaran chronostratigraphic framework and to clarify the correlation problem of the Doushantuo Formation, we reinvestigated the Tianjiayuanzi section, which is the stratotype section of the Doushantuo Formation. The new carbon isotope and sequence stratigraphic data, as well as the integrative correlation of the Tianjiayuanzi section with other sections in the Yangtze Gorges area demonstrate that there are four negative carbon isotope excursions (N1-N4) in the Doushantuo Formation in the Yangtze Gorges area. The N1 (CANCE) excursion occurs within the cap carbonate interval at the base of the formation. Extreme negative δ13C values (< -18%) are recorded within this interval from most of the sections in the Yangtze Gorges area. The N2 (WANCE) excursion, with δ13C values shifting from +6% to -1%, occurs in the middle of Member 2 at a major sequence boundary in the middle of the formation. The N3 excursion is situated in a horizon near the boundary between Member 2 and Member 3 of the formation and is characterized by δ13C values down to -6%. The N4 (DOUNCE) excursion with a nadir of δ13C values as low as -9.6% at the top of the formation represents the most distinct negative carbon isotope excursion in the Ediacaran. New observations in the field confirm the presence of a sequence boundary at a karstic surface in the upper part of the Doushantuo Formation, which coincides with the beginning of the nadir of δ13C values within the DOUNCE. Additional δ13C data from the basal Dengying Formation indicates that the DOUNCE interval with the most negative δ13C values crosses entirely the black shale Member 4 at the top of the Doushantuo Formation. [ABSTRACT FROM AUTHOR]