“虚拟井”技术在复杂气藏建模中的应用

Application of pseudo-well construction techniques to geological modeling of complex gas reservoirs

在气藏开发早期,普遍存在钻井少且分布不均,地质资料缺乏,动态资料有限等问题,难以为气藏数值模拟提供高精度的数据体。为此,针对气藏开发早期储层的不确定性因素,提出采用"虚拟井"技术进行定量化表征的解决方案,即:充分利用测井资料纵向分辨率高、地震储层横向预测的优势以及地质认识上的空间整体性控制,在边部井网稀疏的地方合理构建虚拟井作为插值控制,采用确定性建模与随机建模相结合、静态与动态相结合的原则,以先进的建模软件为依托,优选合理的建模方法,最终建立了薄差储层与优质储层、边部区域与中心区域、勘探与开发一体化的气田精细三维地质模型。实例验证结果表明:合理构建虚拟井能够有效降低地质模型的不确定性,提高储层地质建模的精度。

High-precision data volumes for numerical simulation of gas reservoirs are usually unavailable in the early stage of development due to the limited number and uneven distribution of wells,and lack of geologic data or enough performance data.In view of the uncertainty of reservoirs in the early development stage,it is proposed to use pseudo-well technique to quantitatively characterize the gas reservoirs.The high vertical resolution of logging data,the advantages of seismic lateral reservoir prediction,and the spatial integrity of geologic understandings were fully used to rationally construct pseudo-wells in the periphery areas where well patterns are sparse for interpolation control.According to the principle of integrating deterministic modeling with stochastic modeling and integrating static modeling with dynamic modeling,advanced modeling software and approaches were used to build a fine 3D geologic model for the gas field that integrates poor thin reservoirs with quality reservoirs,the periphery area with the core area,and exploration with development.Case studies show that rational construction of pseudo-wells can effectively make much clear the geologic models and improve the precision of geologic modeling of reservoirs.