准噶尔盆地玛18井区百口泉组基准面旋回及其对砂体的控制  

Base-level Cycles and Its Effect on Sandbody Distribution in Baikouquan Formation, Ma18 Block in Junggar Basin

作　　者：卢志远 马世忠[1] 张景[2] 朱健[2] 周恒 王黎[2] 张方[2] 朱越 LU Zhiyuan;MA Shizhong;ZHANG Jing;ZHU Jian;ZHOU Heng;WANG Li;ZHANG Fang;ZHU Yue(School of Earth Sciences, Northeast Petroleum University, Daqing 163318, China;Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 834000, China)

机构地区：[1]东北石油大学地球科学学院,大庆163318 [2]中国石油新疆油田分公司勘探开发研究院,克拉玛依834000

出　　处：《高校地质学报》2019年第2期287-294,共8页Geological Journal of China Universities

基　　金：国家自然科学基金"水平井河道砂体内部构型及对三次采油期剩余油形成机制的研究"(41272153);国家科技重大专项<准噶尔盆地致密油开发示范工程>(2017ZX05070-001)联合资助

摘　　要：三叠系百口泉组是新疆油田的主要储集层之一。应用高分辨率层序地层学基准面旋回原理,依据4口井的岩芯资料、122口井的录井、测井等资料,对准噶尔盆地玛湖西斜坡玛18井区百口泉组各级次基准面旋回界面进行了系统分析,将百口泉组划分为1个长期基准面旋回的上升半旋回、3个中期基准面旋回和18个短期基准面旋回层序。百口泉组下部发育扇三角洲前缘亚相,上部发育前扇三角洲亚相。基准面旋回内砂体特征研究表明:百口泉组底部,可容纳空间增长速率与沉积物供给通量的比值远远小于1 (A/S≤1),水下分流河道砂体大面积连片展布,主要以进积的切叠式为主;百口泉组中部,随着基准面上升,A/S增加,砂体以接触式分布;百口泉组上部,河水动力减弱,河道砂体进一步向后退积,发育远砂坝砂体,砂体以孤立式分布为特征。长期旋回的早中期发育水下分流河道砂体形成了主要的岩性储集砂体;末期湖侵作用形成的湖泛泥岩为油气圈闭提供了良好的盖层。The Lower Triassic Baikouquan Formation is one of the main reservoirs in the Xinjiang Oilfield. Using the basic principle of base-level cycles of high-resolution sequence stratigraphy, we systematically analyze the evolution of all base-level cycles and high-resolution sequence stratigraphic model in the Baikouquan Formation of the Ma 18 block based on core data of 4 wells, and logging and well-logging data of 122 wells. Results show that one long-term, three medium-term and eighteen short-term base-level cycles were classified. Fan-delta front subfacies change to pro-fan delta subfacies from bottom to top during the Baikouquan period. Based on the analysis of single sand body within the base-level cycles, it is indicated that at the bottom of the Baikouquan Formation, the ratio between the growth rate of the accommodation space and the sediment supply flux is far less than 1.0 (A/S ≤ 1). As such,channel sand body distributes contiguously mainly on progradation, and the configuration is in the form of cut-overlay type. In contrast, in the middle of the formation, with the rise of base-level, the ratio of A/S increases and the sand body is distributed by contact. At the upper part, the lacustrine level rises, while dynamic of river is weak. The sand body retrogrades back, and far bar appears. Sand body is distributed separately. Favorable reservoir sand bodies are formed by underwater distributary channel during the mid-early phase of long-term cycle. The lacustrine mudstones formed by late lacustrine transgression provides good cap rocks for hydrocarbon traps.

关 键 词：高分辨率层序地层 基准面旋回 单砂体 百口泉组 玛18井区 玛湖凹陷 

分 类 号：P618.13[天文地球—矿床学]