摘要
塔里木盆地塔北隆起带哈拉哈塘-哈得地区中生界面积超3万km^(2),处于大型单斜背景,油气显示活跃,具有较大的勘探潜力,但多年来未有勘探突破。邻区中石化矿区的发现使得该区的勘探再次提上了日程。基于新处理的三维地震资料,在分析区域地质概况的基础上,系统分析了油源条件、走滑断裂的构造及演化特征和岩性圈闭的形成及封堵条件,明确了该区的成藏模式及有利勘探方向。研究区中生界发育河流-三角洲沉积体系,其中三叠系发育NE-SW向条带状三角洲砂体,侏罗系和白垩系下部发育SE-NW向展布的叠覆浅水三角洲砂体,白垩系上部发育大面积连片状的辫状河砂体。该区经历了3期隆升,发育5期断层,其中中生界的三叠系-侏罗系断层是古生界断层的伴生断层,受古生界断层的发育控制,雁列状NE-SW向展布。白垩系和侏罗系浅水三角洲前缘单一朵体或多个朵体披覆泥岩拼接形成了侧向遮挡,与上倾方向断层联合形成岩性-断层圈闭,三叠系条带状SE方向展布的三角洲砂体和大型河道弯曲部位河道外泥岩遮挡形成岩性圈闭。油气源于古生界古油藏,通过古生界奥陶系断层泄漏后,经中生界伴生断层直接进入中生界圈闭或经中生界断层接替输运进入圈闭而成藏。基于此,认为本区勘探潜力区主要有北部走滑带的侏罗系-白垩系舒善河组三角洲前缘岩性油气藏、三叠系北侧的三角洲前缘砂体和南部河道砂体岩性油气藏和三叠系北部隆起区披覆小型扇体岩性油气藏。断裂组合、砂体展布及披覆泥岩遮挡3个关键控藏要素及其有效配置是塔北隆起带大型斜坡区形成有利岩性、岩性-断层复合圈闭油气藏的重要前提,该认识为该区油气的深化勘探指明了方向,对其他地区岩性、岩性-断层复合圈闭油气藏勘探具有借鉴意义。
[Objective]The Mesozoic strata in the Halahatang-Hade area of the Tabei Uplift belt,Tarim Basin,cover an area of more than 30000 km^(2).It has a large monoclinic background,with active hydrocarbon displays and great exploration potential,but no exploration breakthrough have been made for many years.The discovery of the adjacent SINOPEC mining area promoted exploration in the area.[Methods]Based on the newly obtained 3D seismic data and a regional geological overview,the oil source conditions,structural and evolutionary characteristics of strike-slip faults,and formation and sealing conditions of lithologic traps were systematically analysed,and the reservoir formation pattern and favourable exploration directions in this area were clarified.[Results]In this area,fluvial-delta sedimentary systems developed in the Mesozoic,including a NE-SW-trended delta sand-body developed during the Triassic,the SE-NW-directed shallow water delta sand-bodies developed during the Early Jurassic and Cretaceous,and a large scale of continuous braided river sand-body developed during Late Cretaceous.The study area had experienced three uplift episodes and five faulting episodes.The Triassic-Jurassic fault system accompanied by the Palaeozoic fault system show NE-SW-striked in echelon.The front edge of the Cretaceous and Jurassic shallow water deltas was spliced with a single body or multiple bodies covered with mudstone to form lateral occlusion,which combined with an upwards-dipping fault to form a lithology-fault trap.The Triassic striped sandbody spread in the southeast direction and formed lithology,and the mudstone shading outside the channel at the bend of the large river channel formed a lithological trap.Hydrocarbon sourced from Palaeozoic palaeo-accumulations,migrated through Palaeozoic-Ordovician faults,and directly or successively charged into the Mesozoic trap through the Mesozoic fault.[Conclusion]Based on the hydrocarbon accumulation model,it is believed that the potential exploration areas in the study area mainly include the Jurassic-Cretaceous Shushan River formation Delta front lithological reservoir of the northern strike-slip zone,the delta front sand-body on the north side of the Triassic,and the southern channel sand-body lithological trap,and the northern Triassic descending area covered with small fan lithological traps.The three controlling factors,fault assemblage,sand-body distribution,and mantled mudstone shielding,and their effective allocation are important for guaranteeing the formation of favourable lithologic and lithologic fault combination traps in the large slope areas of the Tabei Uplift belt.The research results point out the direction of further hydrocarbon exploration in this area and are important for guiding hydrocarbon reservoir exploration of lithologic and lithologic fault combination traps in other areas.
作者
石放
王铸坤
李建浪
孙琦
易珍丽
李斌
刘柳
尹太举
SHI Fang;WANG Zhukun;LI Jianlang;SUN Qi;YI Zhenli;LI Bin;LIULiu;YIN Taiju(Tarim Oilfield Company,PetroChina,Korla Xinjiang 841000,China;R&D Center for Ultra-Deep Complex Reservoir Exploration and Development,CNPC,Korla Xinjiang 841000,China;Engineering Research Center for Ultra-Deep Complex Reservoir Exploration and Development,Xinjiang Uygur Autonomous Region,Korla Xinjiang 841000,China;School of Geosciences,Yangtze University,Wuhan 430100,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2024年第4期15-26,共12页
Bulletin of Geological Science and Technology
基金
国家自然科学基金项目(42072119)
中国石油天然气股份有限公司塔里木油田分公司科技项目(041021120183)。
