页岩气评价标准与储层分类

Evaluation criteria and classification of shale gas reservoirs

随着中国页岩气勘探开发的迅猛发展,页岩气评价标准和储层分类方法的建立显得尤为重要。在调研国内外页岩气地质特点、生气能力、储气能力和易开采性等资料的基础上,结合中国四川盆地具体地质情况,筛选出10个储层评价参数,并界定了评价参数分级分值。随后,采用灰色关联分析法定量化各因子之间的大小关系,计算出了各主、次因子的权重和页岩气储层质量综合评价因子,从而进行了储层分类。分析发现,我国四川盆地页岩气储层与美国五大页岩气盆地地质特点极为相似,并且龙马溪组和筇竹寺组储层综合评价因子分别为0.48和0.45,与美国New Albany页岩气盆地储层评价因子相差不大,开发潜力巨大。实例证明,储层分类结果与实际生产情况吻合度非常高。该评价方法可为我国页岩气储层评价和选区提供依据。

Establishment of shale gas evaluation criteria and reservoir classification methods is important for shale gas explora-tion and development .Based on investigation and survey of geological features ,gas generating capacities ,gas storage capacity and recoverability of typical shale gas plays in the world ,10 parameters for shale gas reservoir evaluation were selected in com-bination with the specific geological conditions of Sichuan Basin and their scores for shale gas reservoir classification were also determined.Grey relational analysis method was used to define the relationship between these factors and to calculate the weights of the principle and secondary factors and the comprehensive evaluation factors of shale gas reservoir quality .Shale gas reservoir classification was further performed on the calculation results .Shale gas reservoirs in Sichuan Basin are similar with that in the 5 major shale gas basins in the America .The comprehensive evaluation factors of shale gas reservoirs in the Long-maxi Formation and Qiongzhusi Formation are 0.48 and 0.45 respectively ,which are very close to that of New Albany shale gas basin.Case study shows that the reservoir classification results accord well with the practical production situation .This evalua-tion method can be applied to shale gas reservoir evaluation and selection in China .