随钻跟踪分析精细地震解释技术在克拉美丽火山岩气田开发中的应用

克拉美丽火山岩气藏以深度大、幅度低的隐蔽圈闭为主,储层具有强非均质性,分布规律复杂。研究区内现有三维地震资料分辨率低,仅据此解释预测的气层深度、储层和夹层岩性及分布规律等与实钻资料存在较大差异,需进行井位跟踪分析,实时指导下一步钻探目标或修正钻井轨迹。基于地震褶积模型和实钻结果,通过总结不同火山岩体对应的地震相特征及储层特征,建立了开发井位跟踪研究系列方法。以DX区块4口典型开发井为例,综合应用火山岩体侵入模式、极性识别、波形放大与正演模拟、地震属性精细识别等技术,进行随钻跟踪分析,显著提高了储层钻遇率,最大程度地提高了开发效益。

Seismic updating interpretation with development well information in volcanic reservoir in Kelameili Gasfield in Junggar Basin

As deep and low-relief subtle traps, volcanic reservoirs in the Kelameili Gasfield are characterized by complex distributions and strong heterogeneity. Due to limits of 3D seismic data resolution, there are always some differences between seismic and real drilling data on the depth of gas reservoir tops, lithology, reservoir distribution, and inter-layers. Therefore, seismic interpreters need to update their interpretation with drilling well data, and propose next drilling targets or modify in time drilling trajectory. Based on seismic convolution model and the latest drilling information, we propose in this paper a seismic updating interpretation approach with well information by summarizing different volcanic seismic facies and reservoir characteristics. For four wells in the Block Dixi, we have made seismic updating interpretation with development wells information using volcanic body invasion model, polarity identification, waveform amplification, forward modeling and seismic attribute. The proposed approach improves significantly the reservoir encountering rates, and maximizes the development benefits.