桩西潜山是济阳坳陷构造变化最为复杂的地区，经历了多期构造运动，具有良好的油气勘探开发前景，但对其构造演化过程一直未进行深入研究，影响了勘探开发工作的开展。该文在区域构造演化分析的基础上，利用平衡剖面分析方法对桩西潜山构造演化过程进行了深入研究。结果表明，桩西潜山受控于华北板块，在太古代到中元古代陆核形成后的克拉通构造背景和早古生代稳定的碳酸盐岩为主的沉积条件下，经历了印支期褶皱隆升、燕山期断块抬升和喜马拉雅期拉张块断改造及掩埋3个演化阶段。基岩地层经历了印支期和晚燕山期两期构造挤压活动，但挤压作用较弱；现今褶皱是喜马拉雅期形成的滚动背斜，桩西潜山为低位挤压-拱张褶皱型潜山。桩西潜山储层以下古生界寒武-奥陶系碳酸盐岩为主，潜山构造演化控制了储层分布。储层类型以断裂岩溶带和裂缝为主，其次是风化壳岩溶带，主要形成潜山内幕裂缝性油藏。桩西潜山油气来自孤北洼陷古近系沙三下亚段烃源岩，油气穿过桩南断层运移到潜山成藏。桩西潜山发育挤压-拱张褶皱型和挤压-拉张断块型2种成藏模式，挤压-拱张褶皱型主要分布在背斜构造西翼，挤压-拉张断块型分布在背斜轴部应力最为集中的地区，是富集高产的主要类型。%Zhuangxi Buried-hill is one of the most tectonically complicated regions in Jiyang Depression. It experienced multiphase tectonism with good prospects for oil and gas exploration and development. However, its tectonic evolution has not been studied in detail, impeding the exploration and development work. Here we study the tectonic evolution of Zhuangxi Buried-hill by the method of cross-section balancing on the basis of regional tectonic evolution analysis. Results indicate that Zhuangxi Buried-hill was controlled by the cratonic tectonic setting after the North China continental core formation in Archaean to Mesoproterozoic and was mainly carbonate-based deposition conditions in the early Paleozoic. Zhuangxi Buried-hill experienced three evolutionary stages: the Indosinian folding related uplift, the Yanshanian fault block uplifting, that the Himalayan tectonic uplifting and burial. Bedrock strata underwent two episodes of weak compressional tectonism in Indosinian and late Yanshanian. The present fold is a rolling anticline formed in Himalayan. Zhuangxi Buried-hill is a lower compression-arch fold Buried-hill. The reservoirs in the Zhuangxi Buried-hill are mainly composed of Cambrian-Ordovician carbonate rocks in lower Paleozoic, the tectonic evolution controlled distribution of reservoirs in the Zhuangxi Buried-hill. The reservoir type is dominated by fault karst zone and fracture, followed by the weathering crust karst belt, mainly formed within the fractured Buried-hill reservoirs. The oil and gas of Zhuangxi Buried-hill came from source rocks of the lower part of the third member of Paleogene Shahejie Formation, and then migrated through the Zhuangnan fault to Zhuangxi Buried-hill and formed reservoirs. There are two kinds of accumulation models in Zhuangxi Buried-hill:compression-arch-fold type and compression-tension-block type. The compression-arch-fold accumulation is mainly distributed in the western limb of the anticline. The compression-tension-block accumulation is mainly distributed in the anticline axis region where the stress is most concentrated, and it is the main type of high-yield reservoirs.
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