准噶尔盆地春光探区白垩纪古地貌恢复及其控砂机制  

Cretaceous paleogeomorphology restoration and its controlling mechanism on sand-bodies in Chunguang exploration area,Junggar Basin

作　　者：程逸凡 董艳蕾[1,2] 朱筱敏[1,2] 杨道庆[3] 伍炜 杨棵 苏彬 赵瑞星 乔陈凯 Cheng Yi-Fan;Dong Yan-Lei;Zhu Xiao-Min;Yang Dao-Qing;Wu Wei;Yang Ke;Su Bin;Zhao Rui-Xing;Qiao Chen-Kai(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Henan Oilfield Company,SINOPEC,Henan Nanyang 473132,China;Taizhou Oil Production Plant,SINOPEC East China Oil&Gas Company,Jiangsu Taizhou 225300,China)

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石化河南油田分公司,河南南阳473132 [4]中国石化华东油气分公司泰州采油厂,江苏泰州225300

出　　处：《古地理学报》2020年第6期1127-1142,共16页Journal of Palaeogeography：Chinese Edition

基　　金：国家科技重大专项(编号:2017ZX05001-002-002);国家自然科学基金项目(编号:41202078)联合资助。

摘　　要：古地貌恢复是盆地沉积体系研究的重要手段之一。准噶尔盆地春光探区井位分布不均,无法有效地对白垩系凹陷区的储集层潜力进行评估。首先利用三维地震、测井和岩心等资料,采用高精度古地貌恢复方法,在建立全区层序地层格架的基础上,综合考虑压实校正、剥蚀量恢复和古水深恢复,按砂组恢复出春光探区白垩纪古地貌特征,识别出了下切谷、坡折带和局部凸起等地貌单元。结果表明春光探区白垩系沉积经历了扩张—收缩—逐渐填平补齐的过程,沉积体系继承性较好;精确的古地貌恢复反映了盆地的沉积过程,有助于储集层预测和微相划分,对白垩系沉积特征研究有重要意义。其次,分析了地貌单元对砂体分布和沉积相展布的控制作用,认为研究区古地貌对砂体控制作用明显,其中局部凸起对砂体有分隔作用,坡折带控制着砂体展布和成因类型,下切谷作为搬运通道控制着砂体发育位置和规模。最后,对沟谷体系进行了精细刻画,总结了古沟谷的V-U-W型发育模式,并定量分析其搬运能力。Paleogeomorphology restoration is one of the significant methods of sedimentary study.The distribution of drilling wells in the Chunguang exploration area,Junggar Basin is uneven,which make it hard to evaluate the reservoir potential of the Cretaceous strata effectively in depression zone.Based on 3D seismic data,well logs and core observation,this paper restores the paleogeomorphology precisely by establishing sequence stratigraphy in study area,strata decompaction correction and restoration of denudation and paleo-water depth.The paleogeomorphology restoration of each Cretaceous sand group has recognized several kinds of geomorphologic cells,such as incised valleys,slope break belt and bulges.The restored results show that the sedimentary basin in the Cretaceous experienced the process of expansion,shrink and filled up,and the sedimentary system has great inheritance.Accurate paleogeomorphology restoration can reveal the sedimentary process of basin,which can improve the prediction of reservoir and the division of microfacies and has great significances for the study of sedimentary characteristics of the Cretaceous strata.Then we analyze the geomorphologic cells’control on sand-body distribution and sedimentary facies,and we think that the features of paleogeomorphology have obviously controlled the sand-bodies,e.g.,the bulge can separate sand-bodies,the slope break belt has controls on sand-bodies’thickness variations and origin types and the incised valley serves as transport conduits for sand.Finally,we make detail descriptions of valley systems,summarize the patterns of valley systems(V-U-W)and analyze the sediment transport ability of each type of valley system.

关 键 词：古地貌恢复 控砂机制 沉积体系 春光探区 准噶尔盆地 

分 类 号：P531[天文地球—古生物学与地层学] P512.2[天文地球—地质学]