Middle Yangtze sea-basin over Paleozoic-Mesozoic transition——Sedimental continuity and environmental catastrophe  

作　　者：黄定华 姚凌青 王君慧 郭浩 张恒 段怡春 李斌 张凡 殷鸿福 

出　　处：《Science China Earth Sciences》2002年第8期730-740,共11页中国科学（地球科学英文版）

基　　金：This work was supported by the National Natural Science Foundation of China (Grant No. 49632070); Ministry of Land and Resources of China.

摘　　要：On the centimeter scale of lithologic change, we conduct poly-statistic analysis on the sedimentary behavior and dynamic features of the stratigraphic sequence from upper Dalong formation to lower Daye formation, which across the Permian-Triassic boundary in East Hubei. From the perspective of stochastically dynamic system, the depositional process of upper Dalong formation can be regarded as a stable Markovian process with weakly stratigraphic correlation and randomly lithologic alteration. Compared to it, the depositional process of lower Daye formation was unstable Markovian process with much closer stratigraphic correlation and ordered lithologic change. As for the replacement style of the sedimental cycle, the former was chaotic, while the latter was periodical. Otherwise, although the overall depositional process of the two formations was continuous, their dynamic characteristics were obviously different. So this P-T sedimental boundary can also be regarded as a dynamic limit. It was a kind of depositional reaction in response to a catastrophic alteration when the geological environment was in continuous change but came over a certain threshold state.On the centimeter scale of lithologic change, we conduct poly-statistic analysis on the sedimentary behavior and dynamic features of the stratigraphic sequence from upper Dalong formation to lower Daye formation, which across the Permian-Triassic boundary in East Hubei. From the perspective of stochastically dynamic system, the depositional process of upper Dalong formation can be regarded as a stable Markovian process with weakly stratigraphic correlation and randomly lithologic alteration. Compared to it, the depositional process of lower Daye formation was unstable Markovian process with much closer stratigraphic correlation and ordered lithologic change. As for the replacement style of the sedimental cycle, the former was chaotic, while the latter was periodical. Otherwise, although the overall depositional process of the two formations was continuous, their dynamic characteristics were obviously different. So this P-T sedimental boundary can also be regarded as a dynamic limit. It was a kind of

关 键 词：MIDDLE YANGTZE sea-basin transition of Paleozoic-Mesozoic randomly dynamic system sedimentary environment depositional cycle chaos gradual change catastrophe. 

分 类 号：P736[天文地球—海洋地质]