基于电成像测井资料的砂砾岩储层有效性分类评价方法

An Evaluation Method for Glutenite Reservoir Effectiveness Classification Based on Electrical Imaging Logging Data

砂砾岩储层岩石成分多样、粒度变化大、分选差、非均质性强,单纯应用孔隙度等物性参数评价储层产能的效果较差,而不同类型砂砾岩储层微电阻率成像图具有不同的特征,为此,提出了利用微电阻率成像测井资料评价砂砾岩储层有效性的方法。采用图像处理方法,将微电阻率成像测井彩色图像转化为灰度图像,依据阿尔奇公式建立了灰度与地层孔隙度的回归关系,并通过转换建立非均质特征谱,结合研究区5口井的试油资料,总结了Ⅰ类、Ⅱ类和Ⅲ类储层的非均质特征谱典型模式,建立了储层非均质特征参数与储层产能的关系以及储层有效性分类标准。该标准在研究区10口井储层有效性评价中进行了应用,解释符合率达到85.3%。研究与应用表明,利用微电阻率成像测井资料评价砂砾岩储层有效性的方法可以解决砂砾岩等强非均质储层的产能特征评价难题。

Glutenite reservoirs are characterized by complex rock compositions,large grain size variations,poor sorting and strong heterogeneity,which may induce challenges in reservoir productivity evaluation by using physical parameters such as porosity.Since micro-resistivity imaging in different glutenite reservoirs has different features,glutenite reservoir effectiveness was evaluated based on micro-resistivity imaging logging data.Colored images of micro-resistivity imaging logging are converted to gray images through the image processing method.The regression relation between the gray level and the formation porosity can be established by using the Archie formula,and established the heterogeneous characteristic spectrum by conversion.Based on production test data of five wells in the research area,the typical model of heterogeneous characteristic spectrum for Class I,Class II and Class III reservoirs has been summarized,and found the relationship between heterogeneous characteristic parameters and reservoir productivity as well as the classification standard of reservoir effectiveness.This standard has been applied to the effectiveness evaluation of 10 wells in the concerned area with the coincidence rate of interpretation up to85.3%.The results showed that the micro-resistivity imaging logging data used for evaluation of glutenite reservoir effectiveness can effectively overcome the difficulties in the evaluation of productivity features for glutenite reservoirs and other highly heterogeneous reservoirs.