东海丽水凹陷北部潜山岩性识别及储层预测技术

Lithology identification and reservoir prediction technologies for buried hills in northern Lishui Sag,East China Sea

东海丽水凹陷北部发育西部潜山和东部潜山两大潜山带,二者圈闭成群成带分布,潜山与丽水凹陷生烃主洼中央深洼烃源岩直接对接,供烃窗口大,油气运移条件好,潜山上覆月桂峰组和灵峰组近千米的区域性泥岩盖层,储存条件好,成藏条件优越,但受制于已钻井资料偏少,潜山岩性类型和储层分布特征尚不明确,制约了潜山的勘探进展。通过对已钻井资料和地震资料综合分析,基于丽水凹陷潜山岩性识别及预测技术,采用储层反演、叠后多属性融合等方法建立了丽水凹陷潜山储层评价技术,实现了丽水凹陷北部潜山岩性和储层展布特征的预测,为潜山下一步勘探提供了较好的指导依据。

Two main buried hill belts named West and East are developed in the northern Lishui Sag,East China Sea and in which traps are distributed in groups and zones.The buried hills are directly in connection with the source rock of central sag,the main hydrocarbon-generating sag in Lishui Sag,having the sufficient hydrocarbon supply and favourable condition of hydrocarbon migration.Additionally,the buried hills are overlapped by nearly a thousand meters of regional mudstone blanket of Yueguifeng Formation and Lingfeng Formation,therefore providing the hydrocarbon with good preservation condition.However,even with such excellent reservoir conditions,the lithology type and reservoir distribution characteristics of the buried hills are still unclear due to the limited drilling data,which restricts the further exploration for the buried hills.In this study,we prospectively established the technology of identification and prediction for the lithology of the buried hills in Lishui Sag through a comprehensive analysis of drilling data and seismic data,based on the evaluation technology for buried hill reservoir that is set up by the methods of reservoir inversion and post-stack multi-attribute fusion.The technology established in our research realizes the prediction of the lithology of the buried hills and reservoir distribution in Lishui Sag and provides a valuable guiding basis for the next exploration of buried hills.