摘要
针对塔里木盆地西南部寒武系存在的古隆起陆棚相分歧,利用锆石U-Pb(铀-铅同位素测年)年龄、井-震联合开展了寒武系层序充填与沉积演化的研究。研究表明:在巴楚隆起,寒武系直接覆盖在克拉通结晶基底之上,寒武系沉积充填与前寒武系结构呈“镜像”关系。受前寒武系地形、构造运动和海平面升降控制,塔里木盆地西南部寒武系发育4个Ⅱ级层序,分别为寒武系层序1(玉尔吐斯组—肖尔布拉克组)、寒武系层序2(吾松格尔组—沙依里克组)、寒武系层序3(阿瓦塔格组)、寒武系层序4(下丘里塔格群),共包含7个沉积相、10个沉积亚相。塔里木盆地西南部寒武系层序1—寒武系层序3早、中寒武世巴楚隆起—麦盖提斜坡—塔西南坳陷沉积相为台地—缓坡—斜坡—深水陆棚相沉积,表现为向海凝缩减薄的沉积特征并发育寒武系烃源岩;寒武系层序4晚寒武世塔里木盆地西南部主体演化为局限台地,塔里木盆地西台东盆沉积格局正式形成。
In the southwestern Tarim Basin,studies on the paleo-uplift and shelf divergence have focused on the sedimentary evolution and sequence filling during the Cambrian period.This research used zircon U-Pb dating and well-seismic technologies.The findings indicate that Cambrian deposits overlay the basin's basement structures,particularly in the Bachu uplift area.The Cambrian sedimentation patterns closely mirror the underlying basement tectonics.Influenced by these tectonics,along with tectonic movements and sea-level changes,four distinct sequences emerged in the Cambrian:the Yuertusi to Xiaoerbulake formations,the Wusonggeer to Shayilike formations,the Awatage Formation,and the Lower Qiulitage Formation.Additionally,seven sedimentary facies and ten depositional sub-facies were identified.From the first to the third Cambrian sequence,spanning the early to middle Cambrian,the area transitioned from a platform to a gentle slope,then to a steeper slope and finally to a deep shelf.This progression indicates a retreat towards the sea,fostering the development of Cambrian source rocks.In the late Cambrian,during the fourth sequence,the southwestern Tarim Basin transformed into a restricted platform.This period marked the establishment of the sedimentary framework in the Tarim Basin,with distinct eastern basin and western platform regions.
作者
罗少辉
王蓉英
岳勇
李斌
魏华动
金仙梅
姜忠正
曹杨
LUO Shaohui;WANG Rongying;YUE Yong;LI Bin;WEI Huadong;JIN Xianmei;JIANG Zhongzheng;CAO Yang(Sinopec Northwest Oilfield Company,Urumqi,Xinjiang 830011,China;Research of Shanghai Branch,CNOOC(China)Co.,Ltd.,Shanghai 200335,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《油气藏评价与开发》
CSCD
北大核心
2024年第2期284-296,共13页
Petroleum Reservoir Evaluation and Development
基金
四川省区域创新合作项目“复杂油藏高效开发相关技术研究及推广应用”(21QYCX0048)。
关键词
塔里木盆地西南部
寒武系
前寒武系
层序充填
沉积演化
southwestern Tarim Basin
Cambrian
Precambrian
sequences filling
sedimentary evolution
