Solid state NMR imaging of irreducible water in reservoir cores for spatially resolved pore surface relaxation estimation

Using Magnetic Resonance Imaging and Petrographic Techniques to Understand the Textural Attributes and Porosity Distribution in Macaronichnus-Burrowed Sandstone

“…Nevertheless, MRI has been successfully employed for a variety of petrophysical applications. Examples of these applications include imaging irreducible water in cored reservoir samples (Attard et al 1994), pore-size distribution and wettability in sedimentary rocks (Howard and Kenyon 1992;Howard 1998), and characterizing fluid movement through solids (Guilfoyle et al 1996;Bencsik and Ramanathan 2001). Also, nuclear magnetic resonance (NMR) logging has become an important subsurface analysis technique.…”

Relaxation Time Mapping of ShortT*2Nuclei with Single-Point Imaging (SPI) Methods

“…For inhomogeneous materials, however, measurements in bulk are not sufficient because the NMR relaxation times will vary spatially (23)(24)(25)(26). The oscillating gradient recalled echo method has been used for relaxation time mapping of porous water saturated materials; however, technical limitations on the oscillation period (TE min Ϸ 200 s) limit the shortest measurable relaxation time (27,28). The stray-field imaging (STRAFI) technique has been employed to map very short spin-spin relaxation times (29,30); however, the observed decay is a complex mixture of T 2 (spin-spin relaxation) and T 1 (spin-lattice relaxation in the rotating frame) time constants, which complicates the interpretation (31,32).…”

A review of non-invasive imaging methods and applications in contaminant hydrogeology research

“…Zhang et al (2007) visualized the permeability distribution of a heterogeneously packed quartz sand via T 2 -weighting 1 H MRI at a resolution of 1.875×1.875×2.25 mm 3 . In other studies, unsaturated porous media have also been characterized and water relative permeability can be determined by measuring NMR relaxation time ( T 1 , T 2 ) distributions under drainage conditions (Attard et al, 1994; Chen et al, 1996; Choi et al, 1997; Bird et al, 2005; Ioannidis, 2006). …”