致密油储层可动流体饱和度计算方法——以合水地区长7致密油储层为例  

A method of determining movable fluid saturation of tight oil reservoirs:A case study of tight oil reservoirs in seventh member of Yanchang Formation in Heshui area

作　　者：喻建 杨孝 李斌[1] 刘小静 田建锋[2] 

机构地区：[1]中国石油长庆油田分公司油藏评价处,西安710021 [2]西安石油大学地球科学与工程学院,西安710065

出　　处：《石油实验地质》2014年第6期767-772,779,共7页Petroleum Geology & Experiment

基　　金：国家自然科学基金项目(41202105)资助

摘　　要：致密油储层可动流体饱和度是评价致密油潜力的关键因素之一。核磁共振技术可以获得准确的可动流体饱和度,但因其成本较高、周期较长,应用的普遍性受到限制。核磁共振、恒速压汞和高压压汞的实验原理表明,T2谱、恒速压汞曲线和高压压汞曲线均是岩石孔隙结构的反映,他们之间具有内在的一致性。相同样品的核磁共振和恒速压汞测试结果表明,致密油储层可动流体饱和度与恒速压汞总进汞饱和度相关性极强,可通过恒速压汞总进汞饱和度参数计算致密油储层的可动流体饱和度,而高压压汞7.0 MPa时的进汞饱和度与恒速压汞总进汞饱和度相同,从而提出了利用高压压汞资料计算致密油可动流体饱和度的方法。计算结果表明,合水地区致密油储层可动流体饱和度较高,以Ⅲ类和Ⅳ类储层为主,其次为Ⅱ类储层。The movable fluid saturation is one of the key factors in tight oil evaluation, and can be tested accurately by nuclear magnetic resonance （ NMR） technology. The high cost and long cycle prohibited the widespread use of NMR technology to determine movable fluid saturation. The testing principles of NMR, constantspeed mercury injection and highpressure mercury injection indicated that the relaxation time distributions, constantspeed mercury injection curves and highpressure mercury injection curves are the reflections of pore structures and have the ingenerate consistency. The movable fluid saturations and total mercury saturations of the same samples were tested by NMR and constantspeed mercury injection respectively. Correlation between the movable fluid saturation and the total mercury saturation was closely strong. The movable fluid saturation can be calculated from total mercury saturation. Considering the similarity between total mercury saturation of constantspeed mercury injection and mercury saturation at 7.0 MPa of highpressure mercury injection, a method to determine movable fluid saturation of tight oil reservoirs was proposed based on highpressure mercury injection data. The calculation results indicated that the tight oil reservoirs, with high movable fluid saturation, are mainly typeⅢ and typeⅣ reservoirs, followed by typeⅡreservoir.

关 键 词：可动流体饱和度 孔隙结构 核磁共振 恒速压汞 高压压汞 致密油 合水地区 

分 类 号：TE122.221[石油与天然气工程—油气勘探]