核磁共振录井技术影响因素分析与实验研究  

The analysis and experimental study for the affecting factors on NMR logging technology

作　　者：王守军[1] 孙丕善[2] 郭明科[3] 王晓惠[1] 

机构地区：[1]胜利油田地质录井公司 [2]胜利油田分公司 [3]辽河油田录井公司

出　　处：《录井工程》2007年第4期17-21,共5页Mud Logging Engineering

摘　　要：核磁共振录井技术在随钻储集层物性和流体评价中具有分析参数多、速度快等优点,但在应用过程中存在着一定的系统误差和偶然误差。在深入分析其影响因素的基础上,以实验分析数据为依据,针对应用过程中仪器参数、岩石性质、流体性质、取样与样品类型的影响以及测试过程中的影响因素,开展了分析与实验研究。结果表明:影响核磁共振录井的因素主要包括仪器的系统误差,取样、选样及处理过程中的偶然误差以及测试样品性质(岩石性质和流体性质)造成的误差;在仪器允许的范围内应加大样品用量,以提高地层代表性和测量值的准确性;t_2截止值有随着岩石骨架颗粒的增大而增大的趋势,并主要分布在10～20 ms之间;渗透率模型中的经验常数c值选择10较为合适;Mn^(2+)的质量分数、浸泡时间对含油饱和度测量结果影响较大,在Mn^(2+)质量分数为2.0%、浸泡时间在24～36 h的条件下,能够真实地分辨油水信号。NMR logging technology has the advantages of more parameters and fast analysis velocity during the evaluation of reservoir physical property and fluid while drilling,but there exists certain systematic error and occasional error during the application.On the basis of deep analysis on its affection,taking the experimental and analyzing data as the basis,being directed against the influence from the instru ment parameter,rock property,fluid property,the influ- ence of sampling and sample type and the factors during the test,the analysis and experimental study are carried out. The results show that the influencing factors on NMR log ging mainly include the instrument systematic error,occa sional error during sampling,sample choosing and process- ing and the error that is caused by sample property testing (rock property and fluid property),the sample using a- mount should be increased within the instrument allowance in order to improve the formation representativeness and the accuracy of the measuring value,t_2 cut off has the increas ing trend with the increase of the rock matrix grain and it mainly distributes among 10～20ms,10 is suitable to be se lected to be as the empirical constant c value in the permeabili ty model,the mass fraction and soaking time for Mn^(2+) have more influence on measuring results of oil bearing saturation, and the oil and water signals can be truly distinguished when Mn^(2+) mass fraction is 2.0% and soaking time is 24～36h.

关 键 词：核磁共振录井 误差 T2谱 影响因素 孔隙度 渗透率 

分 类 号：TE142[石油与天然气工程—油气勘探]