caa a22 4500 605545839 CHVBK 20210128100937.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s00723-015-0711-2 doi (NATIONALLICENCE)springer-10.1007/s00723-015-0711-2 The Observation of Residual Oil Evolution During Waterflooding Using NMR D - T 2 Maps [Elektronische Daten] [Yukai Qi, Naigui Liu, Weimin Wang] By supplementing standard relaxation time measurements with diffusion information, nuclear magnetic resonance (NMR) D-T 2 mapping provides a powerful tool for characterizing fluids in a core. In this study, a D-T 2 mapping technique was designed and applied to investigate waterflooding behavior and pore-level residual oil distributions. NMR measurements were conducted at different stages of the waterflooding process, and corresponding D-T 2 maps were acquired. The oil and water signals were easily separated using a diffusion coefficient cut-off of 3×10−6 cm2/s. The oil saturation values measured via the NMR method were highly consistent with the volumetric method results. The pore-level residual oil distributions could be calculated by analyzing the oil T 2 spectra during waterflooding. The injected water was found to preferentially displace oil in large and medium-sized pores having relatively low capillary pressures. The final residual oil saturation measured via the NMR method was 18.9%, with 15.7% occurring in medium-sized pores (10ms<T 2<100ms). Springer-Verlag Wien, 2015 Qi Yukai Institute of Geology and Geophysics, Chinese Academy of Sciences, No.19, Beituchengxi Road, Chaoyang District, 100029, Beijing, China aut Liu Naigui Institute of Quantum Electronics, School of Electronic Engineering and Computer Science, Peking University, 100871, Beijing, China aut Wang Weimin Institute of Quantum Electronics, School of Electronic Engineering and Computer Science, Peking University, 100871, Beijing, China aut Applied Magnetic Resonance Springer Vienna 46/10(2015-10-01), 1089-1098 0937-9347 46:10<1089 2015 46 723 https://doi.org/10.1007/s00723-015-0711-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00723-015-0711-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Qi Yukai Institute of Geology and Geophysics, Chinese Academy of Sciences, No.19, Beituchengxi Road, Chaoyang District, 100029, Beijing, China aut NATIONALLICENCE 700 1- Liu Naigui Institute of Quantum Electronics, School of Electronic Engineering and Computer Science, Peking University, 100871, Beijing, China aut NATIONALLICENCE 700 1- Wang Weimin Institute of Quantum Electronics, School of Electronic Engineering and Computer Science, Peking University, 100871, Beijing, China aut NATIONALLICENCE 773 0- Applied Magnetic Resonance Springer Vienna 46/10(2015-10-01), 1089-1098 0937-9347 46:10<1089 2015 46 723