A new method of estimating NMR T2spectrum of sandstone

作者：Yan Weichao; Sun Jianmeng; Cui Likai; Yan Guoliang

来源：Journal of China University of Petroleum(Edition of Natural Science), 2017, 41(1): 60-68.

DOI：10.3969/j.issn.1673-5005.2017.01.007

• Delaunay tessellations
• Digital core
• Monte Carlo approach
• Nuclear magnetic resonance(NMR)
• Process-based
• Relaxation mechanism
• Surface-to-volume ratio
• Transverse relaxation time

Based on nuclear magnetic resonance(NMR)relaxation mechanism and three-dimensional digital core technology, a new method of estimating the spectrum of sandstone transverse relaxation time (T2) is established. A process-based method was used to reconstruct 3D digital rock models of sandstone. Sandstone microstructures were divided into tetrahedral pore units using Delaunay tessellation. Considering the geometry and using a Monte Carlo approach, the surface-to-volume ratio (S/V) of each pore unit was calculated, and then the T2spectrum of sandstone could be simulated. After a large number of simulations, suitable parameters were selected in order to reduce calculation errors. Unimodal and bimodal T2spectrum were considered;both results agreed well with laboratory tests. This new method is helpful in studies of different NMR response effects with varying grain sizes or pore structures.

• 出版日期2017
• 单位中国石油大学（华东）