Fluid identification method based on 2D diffusion-relaxation nuclear magnetic resonance (NMR)

Abstract

Based on current acquisition modes of MRIL-Prime NMR logging tool, 2D NMR signals could be obtained by the combination of logging data from different modes, then the fluid properties in complicated reservoirs could be distinguished by 2D diffusion-relaxation NMR logging data distribution of pore fluids, generated by multi-echotrain joint inversion. In comparison with 1D NMR logging, this method could increase fluid information in diffusion regime, separate oil, gas and water signals in 2D space and enhance the identification capacity of fluid properties from NMR logging. The 2D NMR logging in the multi-echowave interval was applied in the oil pays in Well A and the water layers in Well B in the Nanpu Sag by MRIL-Prime tool, and the interpretation matches the well testing result. It indicates that 2D NMR logging has advantages on the identification of light oil, and fluids in macropore reservoirs than 1D NMR logging. Key words: 2D NMR logging, acquisition mode, joint multi-echotrain inversion, diffusion coefficient