三湖地区疏松砂岩测井资料弹性参数分析

Analysis of elastic parameters with log data of unconsolidated Sandstone in sanhu area

柴达木盆地三湖地区储层为疏松砂岩,取心收获率低,难以用于岩石物理实验室分析,测井岩石物理分析技术不受取心条件限制,且能综合反映地下岩石的真实情况,利用测井资料对三湖地区弹性参数进行了直方图和交会图分析。结果表明,体积模量、拉梅系数、纵横波速度比和泊松比对气层敏感,在含气砂岩段均表现为低值特征;应用不同敏感性空间的弹性参数进行交会分析,可以预测三湖地区的有利储层。为了更好的与地震解释相结合,建立了研究区岩石物理模板用以指导实际地震数据的定量解释。

The reservoirs of Sanhu area in Qaidam Basin are unconsolidated sandstone.It is difficult to analyze the petrophysical characteristics of unconsolidated sandstone in laboratory due to the low core recovery.Petrophysical log analysis is not restricted by the core conditions,and can reflect the actual conditions of the underground rock comprehensively.Based on log data,the elastic parameters of Sanhu area are used to make histogram analysis and cross plot analysis of different fluids and lithology.The result shows that bulk modulus,Lame coefficient,compressional velocity and shear velocity ratio and Poisson's ratio are sensitive to gas-bearing formation and these parameters are low characteristic in gas-bearing sandstone reservoirs.The favorable reservoir of Sanhu area can be predicted through the cross plots of different sensitivity parameter spaces.To better integrate with seismic interpretation,a template was constructed to provide guidance for the quantitative seismic interpretation of hydrocarbon-bearing reservoirs.