PARTIALLY RESTRICTED DIFFUSION IN A PERMEABLE SANDSTONE - OBSERVATIONS BY STIMULATED ECHO PFG NMR

被引：79

作者：

FORDHAM, EJ

GIBBS, SJ

HALL, LD

机构：

[1] Schlumberger Cambridge Research Ltd., Cambridge, CB3 0HG

[2] Herchel Smith Laboratory for Medicinal Chemistry, Cambridge University School of Clinical Medicine, Cambridge

来源：

MAGNETIC RESONANCE IMAGING | 1994年 / 12卷 / 02期

关键词：

POROUS MEDIA; RESTRICTED DIFFUSION; ALTERNATING GRADIENTS;

D O I：

10.1016/0730-725X(94)91536-9

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：

We demonstrate a variant, insensitive to eddy current effects, of an alternating pulsed field gradient technique designed to null the effect of background gradients in liquid-saturated porous media, using a 38 mm diameter sample of a natural sandstone. Measurements of the effective diffusivity confirm predictions of a decline as the square root of an effective diffusion time. A value of the ratio S/V-p for the dominant pores is extracted, yielding with T-1 a value for the surface relaxivity. We test also a geometry-dependent data collapse recently suggested for a range of diffusion times and wavenumbers. The data agree with a sheet-like pore model for this granular sandstone, and fail to agree with a tube-like model; a pore length scale is also extracted.

引用

页码：279 / 284

页数：6

共 15 条

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