应用流体包裹体分析、盆地模拟和有机地球化学等手段,研究东海西湖凹陷平湖构造带超压系统与油气成藏的相互关系.研究结果表明:平湖构造带油气主要来源于平湖组煤系源岩,而且油气主成藏期为晚期,与生烃增压的形成期大致相同,另外油气藏多分布在超压顶界面附近,这些均指示超压与油气成藏存在密切关系;镜质体反射率、地温梯度及包裹体均一温度反映的热异常,储层物性、非均一捕获的包裹体、"气烟囱"反映的流体压力异常、凝析油轻烃组分反映的组分异常证实研究区流体在超压主导下晚期高效率快速流体;高压流体的泄压排放诱发断裂开启,并为流体运移提供动力,从而控制油气在超压界面附近高效成藏.%The relationship between overpressure and hydrocarbon accumulation was investigated using fluid inclusions, basin simulation and organic geochemistry. The results show that oil-gas in Pinghu structural belt is mainly derived from coal-measure source rocks in Pinghu formation. The main oil-gas accumulation occurred in late stage which is approximately consistent with the forming time of overpressure resulted by hydrocarbon generation. Besides, oil-gas pools are distributed near top overpressured surface. Overpressure is closely linked to hydrocarbon accumulation. The thermal anomaly from vitrinite reflectance, geotemperature gradient and homogenization temperatures of fluid inclusion, abnormal fluid pressure from physical property of reservoir, fluid inclusion with non-homogeneous capture and gas chimney, and abnormal components from light hydrocarbon indicate that efficient rapid fluid flow is controlled by overpressure. The discharging of high-pressure fluids induces opening of faults and provides power of fluid migration.
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