川东南庙高寺—二里场地区下三叠统嘉陵江组层序地层特征研究

Stratigraphic sequence features of the lower Triassic Jialingjiang formation of the Miaogaosi-Erlichang region in southeast Sichuan

依据层序地层学原理,结合研究区实际情况,识别出了嘉陵江组层序关键界面。以岩性、测井资料、地层叠置结构关系、沉积相序变化为依据,将庙高寺-二里场地区划为2个三级层序,6个四级层序和15个五级层序。以此为基础建立起层序地层格架,层序横向发育稳定,TST时期形成开阔台地相,HST时期形成局限台地相;纵向上,两个三级层序的海侵和高位体系域厚度有所差异。

On the basis of classical theory of sequence stratigraphy, the lower Triassic Jialingjiang formation in the Miaogaosi-Erlichang region can be dividedinto two third-order sequences according to the lithologic feature, log wells, the superimposed style of the formation in third-order sequence and sedimentaryface sequence. It includes six fourth-order sequences and fifteen fifth-order sequences. Furthermore, sequence framework of the Jialingjiang formation shows that the sequence develop horizontally steady. Open platform facies broadly developed in TST. Restricted platform broadly developed in HST. Obvious thickness divergence exists between the two third-order sequences in HST and TST. M