四川盆地浅气层测井泥质参数校正模型

A CORRECTION MODEL FOR LOGGING SHALE PARAMETERS IN SHALLOW GAS LAYERS OF SICHUAN BASIN

四川盆地浅气层具有低孔低渗、泥质含量变化大、非均质性强的特点,造成四川盆地浅气层储层有别于其他油田的常规砂岩储层。对四川盆地浅气层进行测井解释,如果未做泥质参数校正,会使流体性质判别失误,孔隙度、渗透率、含水饱和度计算不准。为此,对测井参数泥质校正模型做了研究,包括泥质对声波时差影响的校正、泥质对体积密度影响的校正、储层泥质中子孔隙度的确定、含泥质储层电阻率值的校正。通过对某井泥质参数的校正,然后利用常规测井解释,证明了四川盆地浅气层测井泥质参数校正模型使用效果较好,测井解释结果符合率高,可推广应用于生产。

The shallow gas layers in the Sichuan Basin, different from the conventional sandstone reservoir in other fields, are characterized by low porosity, low permeability, strong variation of shale content, as well as strong heterogeneity. Without shale parameters correction, the fluid detection results will be wrong with inaccurate porosity, permeability, water saturation in logging interpretation of shallow gas layers in the Sichuan Basin. Therefore, the paper studied the correction model for logging shale parameters, including correction for the effect of the shale on the sonic wave time, and correction for the effect of the shale on the volume density, the shale neutron porosity estimation, as well as the resistivity correction of the shale reservoir. By citing an example of shale parameters correction along with conventional logging interpretation, the paper verified that good results can be gained by using the correction model for the logging shale parameters in shallow gas layers of the Sichuan Basin, and its logging interpretation results are very consistent with the real data, therefore, this correction model can be popularized and applied.