塔中低凸起东端冲断构造与寒武系内幕白云岩油气勘探

作    者:杨海军,韩剑发,李本亮,罗春树,李传新
单    位:中国石油塔里木油田分公司勘探开发研究院
基金项目:
摘    要:
塔里木南缘早古生代板块构造控制了塔南—塔中从伸展到挤压的演化。寒武纪—早奥陶世板缘拉张控制了塔中北斜坡断陷构造。中奥陶世北昆仑洋盆关闭后塔中前缘隆起。晚奥陶世—晚泥盆世塔中前陆冲断与走滑构造变形。晚奥陶世—泥盆纪塔南前陆冲断由东南向西北方向传播,形成塘北—塔中南—5号断裂等弧形断裂体系和塔中低凸起中西段与Ⅰ号断裂带小角度斜交的走滑断裂体系。塔中低凸起位于前陆冲断带的前锋位置。前陆冲断的传播受控于两个滑脱层,一是沿中寒武统内部膏盐岩的滑脱层,形成弧形冲断构造,终止于塔中南缘断裂带和塔中北缘断裂带的东端;沿该滑脱层形成大量的冲断构造将中寒武统以上的勘探目的层系抬升到浅层,成为目前主要钻探的对象;二是沿中地壳韧性变形带的滑脱层,形成塔中Ⅰ号断裂带北缘东端的弧形构造带,沿该滑脱层形成的基底卷入的冲断构造,将中寒武统膏盐岩封盖层以下的成藏组合抬升到浅层,一方面成为油气长期运移聚集成藏的重要部位,同时又使得该部位成为可以钻探到的潜在勘探领域。本文根据塔中寒武系内幕白云岩的油气成藏条件,提出了油气勘探的建议。
关键词:塔中地区;寒武系;冲断构造;构造特征;白云岩储集层;油气勘探

Characteristics of Thrust Nappe in the Eastern Segment of Tazhong Arch and Oil Prospecting of Cambrian Dolostone Reservoirs, Tarim Basin

Author's Name: Yang Haijun,Han Jianfa,Li Benliang,Luo Chunshu,Li Chuanxin
Institution: Institute of Petroleum Exploration & Development,PetroChinaTarim Oilfield Company
Abstract:
Based on analysis of the regional geology and the seismic interpretation, it is deemed that tectonic evolution from extension to compression in Tazhong Arch was controlled by activity of the south margin of the Tarim plate during early Paleozoic time. Extension and rifting occurred in the north margin of Tazhong Arch under the control of extension in passive continent margin during Cambrian to early Ordovician time. The thrust nappe and strike-slip deformation formed from late Ordovician to late Devonian. The foreland thrust deformation was propagated from southeast to northwest during late Ordovician time, which resulted in two detachment layers. One is the Cambrian evaporite layer and the other is the ductile layer in the middle crust. The thrusting uplifted the inner dolostone reservoirs in the detach ment layers be shallow, which advanced the achievement of hydrocarbon accumulation and also becomes the potential reservoirs that is easy to drill now. it is suggested to pay an attention to oil exploration of the primary paleo-reservoirs that are located at the hanging wall of thrust faults or are capped by Middle-Upper Ordovician rocks.
Keywords: Cambrian; Thrust; Structural deformation; Structural characteristics; Dolostone reservoir; Petroleum Ex ploration; Tazhong Arch; Tarim Basin
投稿时间: 2010-07-21  
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