黔南Triticites带旋回层序碳同位素特征及冰川型海平面变化

CHARACTERISTICS OF CYCLE-SEQUENCE,CARBON ISOTOPE FEATURES AND GLACIO-EUSTASY OF THE TRITICITES ZONE IN SOUTHERN GUIZHOU

应用层序地层学理论对黔南独山地区晚石炭世麦粒(竹蜓)(Triticites)带地层进行了详细的沉积层序分析和系统的碳同位素测定,识别出2个三级沉积层序和17个准层序,其可与北美中大陆同期地层中发现的2个三级沉积层序和17个亚层序对比,是晚石炭世Gzhelian期存在全球沉积记录同时性的佐证。同时探讨了碳同位素演化与全球海平面变化之间的内在联系,总结出沉积层序内碳同位素演化规律。

In light of the principle of sequence stratigraphy, detailed analysis of depositional sequences and systematical carbon isotope measurements have been done for the Triticites Zone of the typical Late Carboniferous Section exposed in the Dushan area of southern Guizhou. Two sequences and seventeen parasequences, which can be correlated with two sequences and seventeen subsequences in the North American Midcontinent, have been distinguished in the Gzhelian, which provides convincing evidence of the global synchroneity of the depositional records. The inernal relations between carbon isotope evolution and eustasy have been studied, and the evolutional characteristics of carbon isotopes in a depositional sequence have been summarized.