珠江口盆地恩平凹陷文昌组浊积体含油气性分析

岩性油气藏是目前油气勘探开发的重要方向和热点研究领域。珠江口盆地恩平凹陷古近系文昌组发育一厚300余米、面积约140 km2的浊积砂体，其上下岩性均为深湖—半深湖相暗色细粒沉积物。文昌组是该盆地最主要的烃源岩，具有形成岩性油气藏的物质条件。以地震资料为主，结合地质和测井等综合技术，对该浊积体的含油气性进行了综合分析。研究表明，浊积体具有低频振幅能量增强、高频振幅能量降低的特点；同时AVO异常，在浊积体下部表现出同相轴下拉现象。EP17 3 1井钻遇该浊积体边缘，在浊积砂体深度（4 552～4 642 m）出现异常高压。这些特点都是含油气的表现。因此，该浊积砂体是有利的勘探目标，也是该区获得油气勘探开发重大突破的希望所在。

Analysis of the Oil-and Gas-Bearing Turbidite Within Wenchang Formation in Enping Depression,Pearl River Mouth Basin,China

Exploration and development of lithologic oil-gas reservoirs are important directions and hot research areas.Zhu-1 Depression of Pearl River Mouth Basin has an annual crude oil output over 10 million tons,but the industrial value of the reservoir has not been found in sub-tectonic units:Enping Depression.In lower Tertiary Wenchang Formation in Enping Depression,there is a set of turbidite sand with 300 meters thickness and 140 km2 area and up and down it are half-deep to deep lacustrine sedimentary facies fine sediments.Geological and geochemical study shows that the main hydrocarbon source rocks from Wenchang Formation developed well and there is the condition to form lithologic Oil-gas reservoirs.Based on seismic data,combined geological and logging technology,hydrocarbon potential of turbidite has been comprehensively analyzed in Enping Depression from Lower Tertiary Wenchang Formation.Seismic information indicates that the turdibite has a low frequency energy boost up and high frequency energy depressed character;AVO anomaly in the same time,in-phase axes descend in the below of the turdibite.Well EP17-3-1 is the margin of the turdibite,an anomaly high pressure has been detected in the 4552-4642 meters depth.All the above shows oil-gas bearing character.So,the turdibite is a favorable exploration object and of the hope for the exploration and development of oil-gas reservoirs in Enping Depression.