准噶尔盆地滴南凸起侏罗系层序地层学研究

滴南凸起侏罗系具有较大的勘探潜力,建立滴南凸起侏罗系层序地层格架并进行层序格架内的沉积相研究,这对该区侏罗系下一步油气勘探尤其是寻找隐蔽油气藏具有重要的现实意义。综合钻井、地震等资料,将滴南凸起侏罗系划分为6个三级层序和17个体系域,应用地震反射终止关系、区域性的岩性界面、古生物分布特征的变化、测井曲线数值和形态突变等进行了层序边界的识别;在依据岩性和测井曲线的变化识别首次湖泛面和最大湖泛面,并结合准层序叠置样式分析的基础上,进行了体系域的划分。分析表明,低位体系域以砾质辫状河沉积为主,水进体系域以"湿地"和河漫滩发育的曲流河沉积为主,高位体系域以河漫滩和河漫湖泊发育的曲流河或砂质辫状河沉积为主;层序和体系域形成的主要控制因素有构造运动、基准面的变化和古气候的变化。

Study on the Sequence Stratigraphy of Dinan Uplift in Junggar Basin

In Jurassic system in Dinan uplift there existed great hydrocarbon potential of exploration,sequence stratigraphic framework was established for studying the sedimentary facies in the framework,it was of great significance of next exploration of oil and gas,especially for looking for subtle pools.By integrating drilling and well logging data,the Jurassic system was divided into 6 III sequences and 17 systematical domains.The sequence boundary was identified by using the terminal correlation of seismic reflection,regional lithologic interface,changes of paleontologic distributive characters,number of logging curve and its style discontinuity.The systematical domain was divided based on the recognition of the first flooded surface and maximum flooded surface and in combination with analysis of parasequence superimposed style.The result shows that the low-stand systematical domain is mainly composed of rudaceous braided river deposits,in the transgressive domain,the meandering river with flood plain and wet land is developed.In the high-stand,meandering river and sandy braided river deposits are developed in the flood plain or flood lake.The main control factors created by the sequence and the domain include tectonic movement and the changes of base level and paleoclimate.