Stratigraphic reconstruction of the Ediacaran Yangtze platform margin (Hunan province, China) using a large olistolith

The southeast-facing slope of the Yangtze platform during deposition of the Ediacaran Doushantuo Formation included several submarine slides and olistostromes of regional extent. These platform margin-derived slides provide windows into the contemporaneous platform margin. This manuscript proposes a paleoenvironmental reconstruction and evolution of the Ediacaran Yangtze platform margin using facies analysis of one of these large-scale slide sheets, which transported shallow-marine platform facies. The base of the slide sheet shows dolomite, chert, evaporites, and phosphorites, lithological association with “tepee” structures and storm-induced microbreccia. Dolomitised limestones with current-related sedimentary structures overlie these facies. Thus, the Ediacaran Yangtze platform may have evolved from a shallow, rimmed platform with shallow, restricted, back-rim, basins developed on the margin to a wave-dominated, shallow subtidal platform. Sequence analysis applied to the slide sheet sediments allows relative dating of the sliding.