塔里木克拉通继承性构造与新生构造并存的时空发育特征及其对海相油气勘探的指导

TIME-SPATIAL DEVELOPING FEATURES OF CO-EXISTED INHERITED AND NEOGENIC STRUCTURES AND THEIR GUIDENCE TO MARINE ORIGIN OIL-GAS EXPLORATION IN THE TARIM CRATON

吴根耀 杨海军 王步清 李曰俊 郑多明 赵岩 刘亚雷

Wu Genyao Yang Haijun Wang Buqing Li Yuejun Zheng Duoming Zhao Yan Liu Yalei

中国科学院地质与地球物理研究所, 北京 100029 2. 中国石油天然气股份有限公司塔里木油田分公司, 新疆 库尔勒 841000

Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Tarim Oilfield br anch Company, PetroChina, Korla, Xinjiang 841000, China

塔里木克拉通由塔北地块与塔南地块晋宁运动时拼合形成,基底构造线因地而异.分阶段讨论了塔南、塔中和塔北地区各期新生构造的形成时代、方向和活动方式,并从与周缘造山带耦合演化的角度探讨了其形成机制,分析了其海相油气勘探意义.与扬子对比发现塔里木的海相油气具以下特点:1)海相油气主要在晚海西-印支期成藏,必须正确认识古油藏在喜马拉雅运动时的调整或晚期次生成藏规律;2)海相沉积的每一地史阶段可能有不同方向的新生构造同时活动,复杂断裂系的多期次活动使早期油气成藏、晚期调整或次生成藏并形成大型复式油气聚集区成为可能;3)古近系膏盐岩层是层间滑动面,古生界不仅后期变形相对较弱,且变形以断裂为主,褶皱的发育受制于断层,含油气构造带主要是断裂带.

The Tarim Craton was created in the Jinningian orogeny by amalgamation of the North Tarim and South Tarim Blocks,with the basement structures being varied in its northern,middle and southern parts.The paper discussed,in succession of tectonic cycles,the neogenic structures in each part,including the ages,orientations and active modes.Their mechanisms were explorated in the light of coupled evolution with the surrounding orogenies.The guidence to marine origin oil-gas exploration was analysed,which revealed the NW-striking neogenic structure in central Tarim controlling the lithologic pool,and the fractures with varied orientation in northern Tarim playing different roles in oil-gas migration.Based on a comparative study with the Yangtze Craton,three distinctions could be summed up.1)The marine oil-gas in the Tarim Craton was mainly accumulated in Late Hercynian-Indosinian.The key was to understand the laws of adjustment or later secondary accumulation of the ancient pool in the Himalayan cycle since the Yanshanian movement being relatively gentle.2)In each tectonic epoch of marine deposition,some neogenic structures with varied orientations might be mobile synchronously,and the Paleozoic neogenic structures might react in the Cenozoic.It was complicated fault systems and their repeated activities that resulted in oil-gas accumulation,later adjustment or secondary accumulation,and creating a large scale multiple oil-gas accumulation play.3)The Paleogene gypsum-salt layer became an interlayer-gliding fault.The Cenozoic thrusts,stretching downwards,converged onto the layer so that the Paleozoic marine deposits and oil-gas pools relatively well reserved.The deformation mode of the Paleozoic was faulting,with folding being constrained by the faults,so the petroliferous structural belts should be fault ones.

国家科技重大专项(2008ZX05008-003-001);国家重点基础研究发展计划(973计划)项目(2006CB202301);塔里木油田科技攻关项目共同资助

https://doi.org/10.11781/sysydz200904315