摘要
基于对准噶尔盆地二叠纪—侏罗纪不整合面的特征识别,通过地层趋势法和沉积速率法相结合计算剥蚀量,采用印模法对古地貌形态进行了刻画,并分析了古地貌演化特征对油气成藏的影响。研究结果表明:①准噶尔盆地二叠系—侏罗系发育3个一级不整合面(C/P,P/T,J/K)和3个二级不整合面(P_(1)/P_(2),P_(2)/P_(3),T/J)。二叠系剥蚀区主要为中拐凸起、达巴松凸起的东南部和西北部,东部凸起带亦有少量剥蚀;三叠系剥蚀区主要为盆地西北缘;侏罗系剥蚀区主要为车排子—莫索湾古隆起带及盆地东部地区。②研究区早二叠世为断陷盆地,西部受正断层控制而尖灭,东部超覆于斜坡之上,中—晚二叠世呈隆坳相间的多沉积中心格局;三叠纪盆地整体沉降,发育3个较大的沉积中心;早—中侏罗世地形平坦,具准平原化特征;中—晚侏罗世盆地南部受构造活动影响发生剧烈沉降,呈“北高南低”格局。③研究区二叠纪—侏罗纪古地貌的演化对储层砂体和烃源岩的展布具有重要控制作用,早二叠世盆地沉积中心发育的烃源岩与隆起区砂砾岩构成了良好的近源生-储组合;中二叠世盆地范围快速东扩及形成的多个沉积中心格局为烃源岩的发育提供了有利条件;晚二叠世盆缘古隆起显著控制砂体展布;三叠纪盆地快速沉降形成深水湖盆,从而沉积了一套厚层烃源岩;中—晚侏罗世平坦地形为煤层的发育创造了有利条件。
Based on the identification of Permian-Jurassic unconformity in Junggar Basin,the erosion amount was estimated through a combination of stratigraphic trend analysis and sedimentation rate methods.Then paleogeomorphology was characterized using impression method,and the impact of ancient landform evolution characteristics on oil and gas accumulation was analyzed.The results show that:(1)Three first-order unconformities(C/P,P/T,J/K)and three second-order unconformities(P_(1)/P_(2),P_(2)/P_(3),T/J)can be identified in Permian-Jurassic of Junggar Basin.The denudation area of Permian is mainly located in the southeast and northwest of Zhongguai uplift and Dabasong uplift,with a small amount of denudation in the eastern uplift zone.The denudation area of Triassic is mainly located in the northwest margin of the basin,while the denudation area of Jurassic is mainly located in Chepaizi-Mosowan paleo-uplift and the eastern part of the basin.(2)In the study area,Early Permian showed fault depression,normal faults controlled the west and the strata terminated,the eastern strata overlaid on the slope,and Middle-Late Permian presented a multi-depositional center pattern of uplift and depression.Triassic experienced overall subsidence,with three relatively large sedimentary centers.In Early-Middle Jurassic period,the terrain was flat with minimal topographical fluctuations.During Middle-Late Jurassic,the southern part of the basin experienced severe subsidence due to tectonic activity,resulting in a topography characterized by high in the north and low in the south.(3)The evolution of Permian-Jurassic paleogeomorphology in the study area has a significant influence on the distribution of sand bodies and source rocks.The source rocks developed in the sedimentary center of Lower Permian basin and the glutenite in the uplift area formed a good near source source-reservoir combination.During Middle Permian,the rapid eastward expansion and the pattern of multiple sedimentary centers provided favorable conditions for the development of source rocks.The paleouplifts at the basin margin in Upper Permian significantly controlled the distribution of sand bodies.In Triassic,rapid basin subsidence led to the formation of a deep-water lake basin,depositing a thick layer of source rocks.The flat terrain during Middle-Lower Jurassic provided favorable conditions for coal seam development.
作者
叶慧
朱峰
王贵重
石万忠
康晓宁
董国宁
娜孜依曼
王任
YE Hui;ZHU Feng;WANG Guizhong;SHIWanzhong;KANG Xiaoning;DONG Guoning;Naziyiman;WANG Ren(School of Earth Resources,China University of Geosciences,Wuhan 430074,China;Key Laboratory of Tectonics and Petroleum Resources,of Ministry of Education,China University of Geosciences,Wuhan 430074,China;Urumqi Branch of BGP INC.,CNPC,Urumqi 830016,China)
出处
《岩性油气藏》
北大核心
2025年第5期122-132,共11页
Lithologic Reservoirs
基金
中石油东方地球物理公司项目“准噶尔盆地二叠系—侏罗系层序格架划分及沉积演化研究”(编号:03-03-2023)资助。
关键词
古地貌恢复
不整合面
剥蚀量
沉积速率法
地层趋势法
印模法
盆地演化
二叠系—侏罗系
准噶尔盆地
paleogeomorphology restoration
unconformity
erosion amount
sedimentation rate method
stratigraphic trend method
impression method
basin evolution
Permian-Jurassic
Junggar Basin
