松辽盆地低孔低渗砂岩油气层的指标判别

Index identification of low porosity & permeability sandstone reservoir in Songliao basin

（1.中国石油化工股份有限公司东北油气分公司，吉林长春130062；2.吉林大学地球探测科学与技术学院，吉林长春130026）

Northeastern Branch Company, SINOPEC, Changchun 130062, China

低孔低渗储层成因复杂，孔隙类型多样，连通性差，导致部分测井信息对地层的反映失真，干扰了储层与干层的划分和油气层的识别。为此提出了识别油层和气层的指标判别法。首先基于常规测井曲线提取各类判别指标——利用自然伽马测井曲线提取储层的判别指标，利用自然电位测井曲线提取产层的判别指标，综合电阻率和声波测井曲线提取油层的判别指标，通过三孔隙度测井曲线提取气层的判别指标；然后基于这些判别指标提出了识别油层和气层的综合指标，该综合指标能够突出储层流体的测井响应。实际应用表明，利用该方法可以有效地区分油层和气层。

The low porosity & permeability reservoir has the characteristics of complicated genetics, multi types of pore and poor connectivity, which leads to the distortion of partial logging on formation and disturbs the classification of reservoirs and non-reservoir and the recognition of reservoirs. Therefore, an index identification method for recognizing oil layer and gas layer was proposed. Firstly, all discriminant indexes are extracted from conventional log, that is extracting discriminant indexes of reservoir from gamma ray log, extracting discriminant indexes of productive layers from natural potential log, extracting discriminant indexes of oil layers from synthetic resistivity and acoustic log, extracting discriminant indexes of gas layers from three porosity log. Then, the synthetic index for recognizing oil layers and gas layers were proposed based on the indexes. The synthetic index can stress the logging response of reservoir fluid. Actual application shows that the method can effectively distinguish oil layer and gas layer.