基于波形指示模拟的致密砂岩储层预测

Prediction of tight sandstone reservoirs based on waveform indication simulation

随着勘探开发的不断深入,地质目标逐渐由常规储层转向非常规储层。鄂尔多斯盆地东北缘砂岩储层纵向叠置、厚度薄、横向变化快,传统的反演技术无法满足薄储层精细预测的要求。波形指示模拟基于波形相控的思路,利用地震波形代替变差函数分析储层的分布特征,可以实现非阻抗参数模拟,是一种高精度反演技术。综合地质、地震和测井资料,基于自然伽马曲线,对鄂尔多斯盆地东缘MG区块进行了波形指示模拟,刻画出目的层砂岩储层的分布规律。结果表明,波形指示模拟具有较高的横、纵向分辨率,反演结果与钻井吻合度较好,与地震波形相关性强,能够反映储层的空间变化情况,且比较符合研究区的地质沉积规律。因此,波形指示模拟作为一种更高效的反演方法,为薄层、薄互储层的精细研究提供了有力支撑,有助于最大程度地实现对气藏资源的开发和利用。

With the deepening exploratory development,geological targets are gradually shifting from conventional reservoirs to unconventional ones.The sandstone reservoirs in the northeast margin of the Ordos Basin are stacked vertically and change quickly horizontally with thin thicknesses.Therefore,traditional inversion technology cannot satisfy the requirements of precise prediction of thin reservoirs.To solve this problem,this paper integrated geological,seismic and logging data based on the GR curve.A wave form simulation of the MG block in the eastern margin of Ordos Basin was conducted,and the distribution of sandstone reservoirs in the target bed was depicted.The results showed that the waveform indication simulation profiles had a high resolution both horizontally and vertically.They were also in line with the drilling well and strongly correlated with the seismic waveform,which could reflect the spatial variation in the reservoir and accord with the law of geological deposition in the study area.Therefore,as a more efficient inversion method,waveform indication simulation provided a strong support for the refined study of thin inter-bedded reservoirs and helped to maximize the development and utilization of gas resources.