作　　者： (冀昆）; (郭少斌）; (李新）; (罗燕颖）; (姜黎明）; (曹先军）;

机构地区： 中国石油集团测井有限公司,陕西西安710077 中国地质大学北京能源学院,北京100083

出　　处： 《天然气地球科学》 2017年第8期1257-1263,共7页

摘　　要： 四川盆地高磨地区龙王庙组储层溶洞、溶孔发育,且多含有沥青侵染暗色斑块。在核磁实验中,样品周表面发育的大量溶孔无法被饱和,从而导致这部分孔洞的核磁信号无法被测量到。在测量烘干岩样时发现岩石干样也会产生一定的核磁信号。因此,针对样品周表溶孔发育和干样信号的问题,设计了一系列对比实验来验证影响的大小及其校正的方法。通过包裹样品周表、包裹样品两端以及裸样测量3种状态下的孔隙度和含水饱和度以及与常规孔隙度、饱和度测量方案值对比表明,包裹对测量准确度有明显的提升。经干样核磁信号与纯沥青核磁信号、沥青—泥砂混合核磁信号对比实验证明该地区碳酸盐岩储层干样的信号为沥青质所产生。扣除干岩样核磁信号后所求得的孔隙度、饱和度与常规测量方案有更好的吻合度。进一步对比不同实验状态下同一样品的T2截止值变化表明,T2截止值不受周表孔洞影响,但受沥青质信号的影响。 Longwangmiao Formation gas reservoir in the Gaoshiti-Moxi area is currently the focus of petroleum exploration and development in Sichuan Provence.The reservoir has dissolved pores and contains asphalt.In usual experiment,plenty of dissolved pores which developed around core＇s surface can＇t be satu- rated by salt water and thus can＇t be detected by NMR.What＇s more, we found NMR signal in dry core samples.After quantities of comparison experiments of pure asphalt and mixture of asphalt and sand, we confirm the NMR signal in dry core sample comes from asphalt.We develop a calibration method of dis- solved pores around surface and asphalt NMR signal in dry core sample.The result shows that after calibration,the NMR porosity has better agreement with helium porosity and NMR bound water saturation has better agreement with weighing method.T2 cutoff value can＇t be influenced by dissolved pores around sur- face but must be through asphalt NMR signal calibration.The data through calibration can characterize the fluid＇s and pore^s information of the reservoir more precisely.

关 键 词： 高磨地区 核磁实验 溶孔发育 沥青质