WATER-AIR SATURATION CHANGES IN RESTRICTED GEOMETRIES STUDIED BY PROTON RELAXATION

被引:16
作者
BORGIA, GC
BRANCOLINI, A
BROWN, RJS
FANTAZZINI, P
RAGAZZINI, G
机构
[1] University of Bologna, Istituto di Scienze Minerarie, Bologna
[2] Agip S.p.A., Milan
[3] Claremont, CA 91711-3721
[4] University of Bologna, Dipartimento di Fisica, Bologna
关键词
NMR RELAXATION; POROUS MEDIA; PARTIAL SATURATION;
D O I
10.1016/0730-725X(94)91513-X
中图分类号
R8 [特种医学]; R445 [影像诊断学];
学科分类号
1002 ; 100207 ; 1009 ;
摘要
The results are reported of a systematic T-1 and T-2 investigation of natural (sandstones) and artificial (microporous porcelain) porous media, after each step of a water desaturation process by centrifugation in air. The analysis of the relaxation curves permitted distinguishing well the different behaviour of the natural samples as compared to the artificial ones, which can be explained by the different pore structures. In both kinds of samples the evolution of the relaxation time distributions yielded a clear picture of the changes of the water distribution in the pore framework following the displacement process, until irreducible water saturation was attained. The results are compatible with the assumption of a fixed amount of surface area contributing to the relaxation of decreasing amounts of fluid as S-w is reduced.
引用
收藏
页码:191 / 195
页数:5
相关论文
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