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Comparative measurements between a new logging tool and a reference instrument.

M Locatelli·H Mathieu·S Bobroff·G Guillot·B Zinszner
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Abstract

Measurements were performed on reference samples (D2O-H2O mixtures) and on highly heterogeneous rocks (Vosges sandstone) with a new logging tool designed to give access to a high spatial resolution, below 1.5 cm on the vertical scale, for a toroidal sensitive volume of 20 cm3. The results were compared to measurements obtained on a clinical magnetic resonance imaging (MRI) equipment working at the same frequency (4.3 MHz). T2 differences as high as 30% were observed for the reference samples; the shortest values were obtained with the logging tool. Porosity profiles of the rock samples were also compared to reference profiles obtained with a conventional computed tomography (CT) scanner. Both nuclear magnetic resonance (NMR) measurements underevaluate porosity by 2-4% for short T2 values (< 10 ms).

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Equipment DesignGeologic SedimentsHumansMagnetic Resonance ImagingMagnetic Resonance SpectroscopyPorosityReference ValuesSensitivity and SpecificityTomography, X-Ray ComputedComparative StudyJournal Article

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M Locatelli, H Mathieu, S Bobroff, G Guillot, B Zinszner. Comparative measurements between a new logging tool and a reference instrument.. https://doi.org/10.1016/s0730-725x(98)00047-2

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