地学前缘 ›› 2022, Vol. 29 ›› Issue (6): 188-205.DOI: 10.13745/j.esf.sf.2022.8.19

• 前陆盆地构造理论与勘探实践 • 上一篇    下一篇

准噶尔西部陆内盆地构造演化与油气聚集

王小军1,2(), 宋永3, 郑孟林3,*(), 郭旭光3, 吴海生3, 任海姣3, 王韬3, 常秋生3, 何文军3, 王霞田3, 郭建辰3, 霍进杰3   

  1. 1.中国石油新疆油田公司, 新疆 克拉玛依 834000
    2.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
    3.中国石油新疆油田公司 勘探开发研究院, 新疆 克拉玛依 834000
  • 收稿日期:2022-07-07 修回日期:2022-07-28 出版日期:2022-11-25 发布日期:2022-10-20
  • 通讯作者: 郑孟林
  • 作者简介:王小军(1973—),男,教授级高级工程师,主要从事石油地质综合研究及油气勘探方面的工作。E-mail: wxiaojun@petrochina.com.cn
  • 基金资助:
    中石油前瞻性基础研究项目“地层不整合油气藏成藏主控因素与关键要素定量评价技术研究(2021DJ0405)

Tectonic evolution of and hydrocarbon accumulation in the western Junggar Basin

WANG Xiaojun1,2(), SONG Yong3, ZHENG Menglin3,*(), GUO Xuguang3, WU Haisheng3, REN Haijiao3, WANG Tao3, CHANG Qiusheng3, HE Wunjun3, WANG Xiatian3, GUO Jianchen3, HUO Jinjie3   

  1. 1. PetroChina Xinjiang Oilfield Company, Karamay 834000, China
    2. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China
    3. Research Institute of Exploration and Development, PetroChina Xinjiang Oilfield Company, Karamay 834000, China
  • Received:2022-07-07 Revised:2022-07-28 Online:2022-11-25 Published:2022-10-20
  • Contact: ZHENG Menglin

摘要:

准噶尔盆地西部油气资源丰富,油气分布受构造演化过程控制作用显著。本文根据地表露头、地震、钻井、同位素年代学资料对盆地西部多期构造演化进行了研究,发现现今的盆地结构是造山带与盆地的相互作用下多期成盆演化与构造叠加演变的结果。根据地层不整合接触关系与空间展布特征,将该区构造地层层序划分为石炭系、中下二叠统、上二叠统—三叠系、侏罗系、白垩系、新生界等6个构造地层层序。石炭纪末的构造事件为车排子、中拐凸起和玛湖、沙湾、四棵树凹陷的形成奠定了基础。早二叠世为伸展构造环境,形成玛湖、沙湾及四棵树3个沉降、沉积中心,盆地西部重要烃源岩形成。中二叠世形成坳陷型盆地,沉积、沉降中心由山前向盆地内迁移。中二叠世末构造运动导致了西部山前沉积地层反转与隆升剥蚀,断裂向盆地逆冲。晚二叠世—三叠纪大型坳陷盆地的沉积、沉降中心在沙湾凹陷,受车排子凸起北翼断裂控制,地层向北、西超覆沉积,相继将中拐凸起、玛湖凹陷及山前断裂带埋藏。三叠纪末的构造运动在乌-夏和车排子地区形成向盆地方向的逆冲构造带。前侏罗纪,造山带与盆地表现出不同方式、不同强度构造耦合作用。侏罗纪—白垩纪,西准噶尔的构造活动弱,湖盆地不断扩张,沉积地层不断向造山带方向超覆;沉积、沉降中心由西向东,再由东向西,最后向南迁移演化。新生代,北天山山前强烈拗陷,盆地整体南北向掀斜,形成新近纪前陆盆地。盆地的多期翘倾掀斜作用与后期沉积地层向造山带的超覆沉积作用控制了油气的聚集,被后期埋藏的冲断带成为油气富集带。

关键词: 盆山结构, 盆山耦合, 构造叠加, 构造演化, 准噶尔盆地西部

Abstract:

Based on the surface outcrop, seismic, drilling and dating data, the multi-stage tectonic evolution of the basin-mountain junction zone, western Junggar Basin is studied. The present basin-mountain structure is the result of multi-stage basin evolution under tectonic superposition and basin-orogenic belt interaction, where six tectonostratigraphic sequences—Carboniferous, Lower-Middle Permian, Upper Permian-Triassic, Jurassic, Cretaceous and Cenozoic—are delineated according to stratigraphic unconformities. In the western basin, Late Carboniferous tectonic activities form the Chepaizi and Zhongguai uplifts and Mahu, Shawan and Sikeshu sags. Under Early Permian extensional tectonic environment, three subsidence-sedimentation centers developed in the piedmont of Mahu, Shawan and Sikeshu, while important hydrocarbon source rocks formed in the west of the basin. Late-Middle Permian tectonic movement results in the inversion, uplift and denudation of the western piedmont sedimentary strata and basin-ward thrust fault. Large-scale Late Permian-Triassic depressions are centered in the Shawan sag and controlled by the northern fault of the Chepaizi uplift, with strata overlapping northward and westward burying, successively, the Zhongguai uplift, Mahu sag and piedmont fault belts. Pre-Jurassic tectonic coupling between the orogenic belt and basin varies in both style and intensity: From the Jurassic to Cretaceous, weak tectonic activities lead to continuous basin expansion and strata overlapping toward the orogenic belt, along with S-N/E-W migration of subsidence-sedimentation centers. While in the Cenozoic, strong depression in the North Tianshan results in the whole basin to tilt N-S, forming a Neogene foreland basin. Eventually, the multi-stage basin tilting/overturning and the late-stage overlaying of sedimentary strata over orogenic belt control the hydrocarbon accumulation in the western Junggar Basin, where late-stage buried thrust belt becomes the oil/gas enrichment zone.

Key words: basin-mountain structure, basin-mountain coupling, tectonic superposition, tectonic evolution, western Junggar Basin

中图分类号: