Numerical Calculation of NMR Response for the 3D Digital Core Constructed with CT Images of the Tight Rock

Abstract:

The tight rock often has low porosity, low permeability and poor pore connectivity, which it is difficult for formation evaluation. Nuclear Magnetic Resonance (NMR) logging is widely used in fluid typing and reservoir parameters determination to provide the information of porosity, permeability and pore size distribution. NMR relaxation mechanisms are characterized by the pore-scale petrophysical models. Monte Carlo algorithm describes the Brownian motion of fluid molecules in pore space. In the paper we setup a 3D digital core of the tight sandstone with X-ray computer tomography (CT) images to model NMR response with Monte Carlo random walk algorithm. We compared T₂ distributions from the numerical calculated pulse echo trains from the measurements. The results show that the simulated NMR response is consisted with the experiment.

• Periodical: Applied Mechanics and Materials (Volumes 719-720)
• Pages: 1089-1092
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.719-720.1089
• Online since: January 2015
• Authors: Yuan Zhong Zhang*, Bao Lei Zhang
• Keywords: 3D Digital Core, CT Images, NMR, Numerical Calculation, Tight Rock

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