• journal_title：Geology
• Contributor：Jiasheng Wang ; Ganqing Jiang ; Shuhai Xiao ; Qing Li ; Qing Wei
• Publisher：Geological Society of America
• Date：2008-
• Format：text/html
• Language：en
• Identifier：10.1130/G24513A.1
• journal_abbrev：Geology
• issn：0091-7613
• volume：36
• issue：5
• firstpage：347

Distinctive sedimentary structures, textures, and extremely negative δ¹³C_carb values from the Ediacaran Doushantuo cap carbonate (ca. 635 Ma) in south China were taken as evidence for a methane hydrate destabilization event, but existing data for a methane-derived δ¹³C_carb signature were reported from a single locality in the Yangtze Gorges area. Here we report negative δ¹³C_carb values as low as −48‰ (Vienna Peedee belemnite) from two additional sections ~6 km and 55 km from the original locality. These negative δ¹³C_carb values were obtained from isopachous cements that fill stromatactis-like cavities, sheet cracks, and fractures, and from partially recrystallized carbonate crusts, consistent with carbonate precipitation at cold methane seeps. The new data support a widespread methane release event following the Nantuo glaciation in south China (ca. 635 Ma), which may have contributed to the origin of unusual sedimentary and isotope features of cap carbonates.