相位域储层预测技术——以胜利油田埕岛地区河道砂为例

不同岩性、物性变化会引起地震信号相位变化，因此从地震数据中有效地提取相位信息并进行分析，可识别特殊地质体以及目标储层。为此，提出并实现了相位域储层预测技术，其核心是相位分解与重构，分析和确定敏感相位是相位域储层预测成败的关键。包括三个步骤：一是地震道的相位分解与重构，可得到相位重构后的分相位地震数据以及相位道集；二是敏感相位分析，根据研究区的地震、地质特征得到对储层变化最敏感的相位；三是应用地震属性分析技术分析分相位数据体，主要包括剖面分析以及切片分析等，最终实现储层预测。模型分析表明，在合成地震记录上不能体现薄层波阻抗的横向差异，而合成地震记录分相位数据放大了薄层内细微的横向阻抗差异，易于识别。实际应用表明，敏感相位数据体的地震属性更清楚地刻画了河道，分辨率更高。

Phase-domain reservoir prediction technology: a case study of channel sand in Chengdao area,Shengli Oilfield

Changes in lithology and physical properties alter the phase of the seismic signal. Therefore, effectively extracting and then analyzing phase information from seismic data are conducive to identifying special geological bodies and target reservoirs. For this reason, this paper proposes and implements a phase-domain reservoir prediction technology, the core of which is phase decomposition and reconstruction. Analyzing and determining the sensitive phase is the key to the success of phase-domain reservoir prediction, and it involves three steps. Step 1 is the phase decomposition and reconstruction of seismic traces, which produce phase-decomposed seismic data and phase gathers after phase reconstruction. Step 2 is sensitive phase analysis, whereby the phase most sensitive to reservoir changes can be obtained according to the seismic-geological characteristics of the study area. Step 3 is the analysis of phase-decomposed data bodies with the seismic attribute analysis technology, mainly involving profile analysis and slice analysis, to ultimately achieve reservoir prediction. The model analysis shows that synthetic seismic records fail to reflect the lateral differences in wave impedance in thin layers, whereas phase-decomposed data of synthetic seismic records amplify the subtle lateral impedance differences in thin layers so that they are easy to identify. The practical application reveals that the seismic attribu-tes of the data body in the sensitive phase depict the channel more clearly and offer higher resolution.