低地层水矿化度油藏原始含油饱和度的确定方法研究

Study on determination method of original oil saturation in low salinity reservoir

苏丹K油田属于典型的低地层水矿化度中渗透性砂岩油藏,在确定油藏原始含油饱和度时,测井法选用印度尼西亚公式解释储层含水饱和度,在此基础上,结合K油田的毛管压力和RFT等资料,研究了利用J函数确定油藏原始含油饱和度的方法。该方法弥补了测井法确定低阻油层段原始含油饱和度失去作用的缺陷,并对测井法确定原始含油饱和度起到一定的约束和验证作用。对比两种方法应用效果可知,综合应用测井法和J函数法能够很好地解决低地层水矿化度且局部存在低阻油层的油藏确定原始含油饱和度的难题,为准确评价油藏储层含油性、定量计算油藏地质储量及开发方案编制等奠定了基础。

Sultan K oilfield is a low salinity and middle permeability sandstone reservoir. According to the characteristics of the reser-voir, when determining the original oil saturation of oil reservoir,using Indonesia formula to explain water saturation in reservoir by log-ging method. On the basis of this research,the author combined the K oil capillary pressure and RFT data,and studied the method to de-termine the original oil saturation of reservoirs by using the J function, this method can make up the defect of well logging method can not determine the original oil saturation of low resistivity oil layer,and can be used to restrain and verify the original oil saturation by logging method. Through the comparative analysis for the application effect of the two methods,it can be knoen that,the comprehensive application of logging method and J function method, can well solve the problem of determining original oil saturation in the low salinity and locally low resistivity reservoir,it can establish base in accurate evaluating oil reservoir,quantitative calculating reservoir geological reserves,and compiling reservoir development plan.