Brown sandstone sample

Two different sandstone samples are used to demonstrate the methodology developed in Sections 2.1-2.3 in one spatial dimension. The first sample is a Bentheimer sandstone sample we have labeled KBE, which is saturated with oil. The second sample is a Brown sandstone sample, labeled MCD, that is saturated with water. 

Fig. 6. One-dimensional CPMG images and the intrinsic magnetization for the Brown sandstone sample (MCD).

Early studies involving NMR include the work by Hanus and Gill is [6] in which spin-lattice relaxation decay constants were studied as a function of available surface area of colloidal silica suspended in water. Senturia and Robinson [7] and Loren and Robinson [8] used NMR to qualitatively correlate mean pore sizes and observed spin-lattice relaxation times. Schmidt, et. al. [9] have qualitatively measured pore size distributions in sandstones by assuming the value of the surface relaxation time. Brown, et. al. [10] obtained pore size distributions for silica, alumina, and sandstone samples by shifting the T, distribution until the best match was obtained between distributions obtained from porosimetry and NMR. More recently, low field (20 MHz) NMR spin-lattice relaxation measurements were successfully demonstrated by Gallegos and coworkers [11] as a method for quantitatively determining pore size distributions using porous media for which the "actual" pore size distribution is known apriori. Davis and co-workers have modified this approach to rapidly determine specific surface areas [12] of powders and porous solids. 

The total Mn concentration in Israeli soils varies from 52.6-810 mg/kg and averages 367 259.8 mg/kg (Han, 1998). The average total Co content is 9.45 4.88 mg/ kg, varying from 3.35 mg/kg in a very sandy soil to 15.9 mg/kg in alluvial soil samples (Han et al., 2002b). In soils on alluvions and derived from aeolian deposits, the Co concentration is 8 mg/kg, and soils from hard limestone contain 10 mg/kg Co. The B concentration in alluvial soils is in the range of 25-85 mg/kg, while brown isohumic soils formed on alluvions contain 25-40 mg/kg B. Mediterranean red soils on limestone are rich in B (190 mg/kg). In soils on calcareous sandstone, alluvions, and aeolian deposits, total Mo content ranges from 4.6-6 mg/kg (Aubert and Pinta, 1977). 

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