准噶尔盆地车排子凸起东缘下切谷特征及其形成机制  

Characteristics and Formation Mechanism of Incised Valley on the Eastern Margin of Chepaizi Uplift,Junggar Basin

作　　者：秦磊 李小刚[1,2] 邱子瑶 李志军[1,2] 徐少华[1,2] 李仪汶 陈岑 汪佳蓓[1,2] 文思奇 QIN Lei;LI Xiaogang;QIU Ziyao;LI Zhijun;XU Shaohua;LI Yiwen;CHEN Cen;WANG Jiabei;WEN Siqi(School of Petroleum Engineering,Chongqing University of Science and Technology,Chongqing 401331,China;Chongqing Key Laboratory of Complex Oil and Gas Exploration and Development,Chongqing University of Science and Technology,Chongqing 401331,China;The First Oil Production Plant of Xinjiang Oilfield Company,CNPC,Karamay,Xinjiang 834000,China)

机构地区：[1]重庆科技学院石油与天然气工程学院,重庆401331 [2]重庆科技学院复杂油气田勘探开发重庆市重点实验室,重庆401331 [3]中国石油新疆油田分公司采油一厂,新疆克拉玛依834000

出　　处：《现代地质》2021年第3期832-840,共9页Geoscience

基　　金：重庆市自然科学基金面上项目(cstc2020jcyj-msxmX0487);重庆科技学院研究生科技创新训练计划项目(YKJCX1920113)。

摘　　要：下切谷是层序地层学研究的重要内容之一,同时也是寻找地层、岩性等圈闭的有利地区。综合利用钻测井、三维地震资料以及地震平面属性信息,在车排子凸起至红—车断裂带区域识别出下切谷沉积体系,对下切谷的发育特征以及形成机制进行分析,结果表明:地震振幅绝对值之和属性体显示研究区发育4条近东西流向的下切谷,主要表现为分支型和单一型的平面形态特征。在地震剖面上,几何形态以V形和U形为主,谷内沉积物充填样式有双向上超充填型和侧向加积充填型,同时具有加积、前积和上超等地震反射特征,属于"顺源堆积"与"溯源堆积"的交互沉积。结合准噶尔盆地车排子凸起中生代构造及气候演化特征分析认为,凸起东缘下切谷形成于晚侏罗世。该时期车排子凸起强烈隆升,相对湖平面急剧下降,河流侵蚀下伏地层导致下切谷形成。下切谷内沉积充填阶段发生在白垩纪。该时期车排子凸起剧烈下沉,相对湖平面上升,下切谷持续性的接受沉积充填。Incised valleys are important research target of sequence stratigraphy,and are also favorable sites to search for hydrocarbon traps.Based on comprehensive drilling and logging,3 D seismic data and seismic plane attribute information,the sedimentary system of incised valleys is identified from the Chepaizi uplift to the Hongche fault zone,and the development characteristics and formation mechanism of the incised valleys are analyzed.The attribute map of the sum of absolute seismic amplitude shows four nearly EW-trending incised valleys in the study area,which mainly show the plane morphological characteristics of branch-and single-type.In the seismic section,the geometry is mainly V-and U-shaped,and the sediment filling patterns in the valley include two-way-up and lateral-accretion filling types.Meanwhile,seismic reflection characteristics of aggradation,progradation and superelevation are present,suggesting interactive deposition of"source accumulation"and"traceability accumulation".Based on the analysis of Mesozoic structure and climate evolution characteristics of the Chepaizi uplift,the local incised valleys were formed in the Late Jurassic,during which the Chepaizi uplift was strongly uplifted and the relative lake level dropped sharply.The river eroded the underlying strata,forming the incised valleys.The filling stage of the valleys occurred in the Cretaceous,during which the Chepaizi uplift subsided readily and rose relative to lake level.

关 键 词：车排子凸起 下切谷 充填样式 平面特征 相对湖平面变化 

分 类 号：TE121.3[石油与天然气工程—油气勘探]