【摘要】 运用层序地层学原理,综合利用露头、岩心、钻井和地震资料,对普光气田上二叠统长兴组剖面层序地层进行研究,识别出2种类型3个层序界面,将长兴组划分出2个三级层序和5个四级层序,其中CSQ1为Ⅱ型层序,CSQ2为Ⅰ型层序,并在层序划分的基础上建立长兴组层序地层格架。CSQ1和CSQ2均由海侵体系域和高水位体系域组成,Ⅰ型层序界面平整,上下呈不整合接触,普遍存在暴露剥蚀,Ⅱ型层序界面CSQ1顶界面为短暂暴露不整合接触,CSQ1底界面在成因上为水下间断不整合接触,在剖面上为整合接触。更多还原

【Abstract】 In Puguang gasfield,the stratigraphic sequence of Upper Permian Changxing Formation is studied based on sequence stratigraphy,and some outcrop,core,drilling and seismic data.This formation can be divided into two third-order sequences and five forth-order sequences,in which CSQ1 is type II sequence and CSQ2 is type I sequence.Meanwhile,its sequence framework is also established based on sequence classification.Result shows that(1) both CSQ1 and CSQ2 sequences are composed of transgressive system tract(TST) and high system tract(HST);(2) for type I,the sequence boundaries are smooth and there are unconformable contacts,and exposure erosion may be often found ;and(3) for type II,the top boundary of CSQ1 is exposed in a short time and there is an unconformable contact whereas the bottom boundary of CSQ1 is a underwater discontinuous unconformable contact in genesis but is conformable contact on the section.更多还原