拟声波宽带约束波阻抗反演在储层预测中的应用

Broadband constrained impedance inversion on pseudo-acoustic curve and its application in reservoir prediction.

鄂尔多斯盆地伊陕斜坡北部塔巴庙工区上古生界储层是典型的岩性气藏,砂体薄,岩性横向变化快而大, 地层砂、泥岩声波速度差异小,声波时差曲线对砂、泥岩的岩性反映不明显,储层预测难度大。在诸多储层预测 方法中,宽带约束波阻抗反演以其综合利用地震、测井和钻井信息的优势而成为储层预测的关键技术。针对工 区特点,在综合工区上古生界储层地质、测井、地震资料的基础上,以拟声波宽带约束反演波阻抗剖面为核心,采 用信息融合技术,总结出一套针对该区上古生界储层预测的技术方法及其关键步骤。实际钻探结果表明,该方 法可以解决该区块目的层储层厚度小、横向变化大的储层空间展布预测技术难题,为该区寻找新的含气区以及 天然气储量计算提供了重要依据。

The Neopaleozoic reservoir in Tabamiao block is a typical lithological gas reservoir. The sand is thin and varies severely in lateral direction, and the velocity difference between sand and shale is little. Therefore it is difficult to distinct sand from shale on AC curves. This paper presents a methodology to predict the Neopaleozonic reservoir in Tabamiao block. The key is to implement broadband constrained impedance inversion on pseudo-acoustic curve. By using information syncretizing technology, a suite of techniques has been developed to predict the Neopaleozoic reservoir. The effectiveness of the proposed method was verified by drilling results.