By researching the lower Triassic meter-scale cyclothem in the westen Pingle geotectogene of Jiangxi province. It shows that the structure mode of lower Triassic third-degree succession in this area is the result of deepen effect stronger than shallow one, different from typical model raised by Exxon, it belongs to special deposi-tional model of " condensed section + HST" , and make division of four third-degree cyclothem on this basis. It also found there have similar sediment structure mode between meter class cyclothem and third-degree cyclothem, both their bottom are drowned unconformity, produced by submerged events under rapid ingression. Both sediment process is Upward criterion gradually becomes shallow, It means that there exists grade and the level of facies. According to the study on cyclothem, this area even Jiangxi province the early Triassic from Paleozoic Epiconti-nental sea grow into crust development stage of epeiric sea. Due to the strongly orogenic role of indosinian movement , the early Triassic sediment sequence totality appears the sediment feature of gradually shallow upwardly. It terminate the paleogeographic environment of epeiric sea with the end of the early Triassic.%通过江西省萍乐坳陷带西段下三叠统米级旋回层序的研究,发现本区下三叠统三级层序结构模式不同于Exxpn提出的典型模式,而是“凝缩段+ HST”的特殊沉积模式,为加深效应强于变浅效应的结果,并依此划分为4个三级旋回层序.同时发现,米级旋回层序与三级旋回层序有相似的沉积结构模式,其界面均为淹没不整合西,为快速海侵作用下的淹没事件的产物.向上两者均为逐渐变浅的沉积过程,说明沉积过程中存在着“相”的等级与层次.依据旋回层序的研窕,本区乃至江西省早三叠世由晚古生代的陆表海进入陆缘海的地壳发展阶段.由于印支运动的强烈造山作用,致使旱三叠世沉积层序总体表现为向上变浅的沉积特征.陆缘海的古地理环境随着早三叠世结束而终结.
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