Analysis of Petrophysical Characteristics and Water Movability of Tight Sandstone Using Low-Field Nuclear Magnetic Resonance
- 62 Downloads
Low-field nuclear magnetic resonance (NMR) coupled with gas–water centrifugation (GWC) was performed to investigate petrophysical characteristics and water movability of the Chang 7 tight sandstone. Microscopic observation, mineral composition analysis and grain size analysis were applied to determine lithology and pore characteristics. Then, the controls of petrophysical properties and geological factors on the water movability were discussed. The results indicate that the T2 distribution of the Chang 7 tight sandstone can be divided into three groups according to the shape, range and amplitude of T2 spectrum. The removable water volume increases with the centrifugal force, but its gradient presents a remarkable difference among the different reservoir types. The final removable water volume (Φmov) at centrifuge force of 400 psi (average value of 5.28%) is approximately half of the total pore volume (porosity). The T2 geometric mean (T2gm), fractal dimension (Df) and NMR permeability calculated from NMR data can be used to characterize the pore structure and petrophysical properties of tight sandstone. The reservoir quality index can also be estimated based on the NMR permeability models. Removable water volume under the different centrifugation conditions is positively related to porosity, permeability and T2gm and negatively related to Df. Furthermore, removable water volume under different centrifugation conditions is positively related to detrital mineral (quartz + feldspar) content and grain size but negatively related to clay content.
KeywordsTight sandstone Petrophysical properties Fractal dimension Water movability Nuclear magnetic resonance
This study was supported by the National Natural Science Foundation of China Project “Effectiveness of micro-nano pore-throat system to oil charging in tight sandstone and its control on oil accumulation” (No. 41472114).
- Amaefule, J. O., Altunbay, M., Kersey, D. G., & Keelan, D. K. (1993). Enhanced reservoir description: Using core and log data to identify hydraulic (Flow) units and predict permeability in uncored intervals/wells. In SPE Annual technical conference and exhibition, 3–6 October, Houston, Texas, USA. https://doi.org/10.2118/26436-MS.
- Anderson, W. G. (1986). Wettability literature survey part 1: Rock/oil/brine interactions and the effects of core handling on wettability. National Municipal Review, 38(10), 1125–1144.Google Scholar
- Arns, C. H., Sheppard, A., Sok, R. M., & Knackstedt, M. A. (2005). NMR petrophysical predictions on digitized core images. In: SPWLA 46th annual logging symposium, New Orleans, Louisiana, June 26–29. https://www.onepetro.org/journal-paper/SPWLA-2007-v48n3a4.
- Brown, R. J. S., & Gamson, B. W. (1960). Nuclear magnetism logging. Journal of Petroleum Technology, 219(8), 199–207.Google Scholar
- Bustin, R. M., Bustin, A. M. M., Cui, A., Ross, D., & Pathi, V. M. (2008). Impact of shale properties on pore structure and storage characteristics. In: SPE Paper 119892 presented at the society of petroleum engineers shale gas production conference in Fort Worth, Texas, November 16–18, 2008. https://doi.org/10.2118/119892-MS.
- Butcher, A., & Lemmens, H. (2001). Advanced SEM technology clarifies nanoscale properties of gas accumulations in shales. American Oil & Gas Reporter, 54, 118–124. https://www.aogr.com/magazine/cover-story/advanced-sem-technology-clarifies-nanoscale-properties-of-gas-accumulations.
- Chen, S., Arro, R., Minetto, C., Georgi, D., & Liu, C. (1998). Methods for computing SWI and BVI From NMR logs. Presented at the SPWLA annual logging symposium, Keystone, Colorado, USA, 26–29 May. https://www.onepetro.org/conference-paper/SPWLA-1998-HH.
- Clarkson, C. R., Jensen, J. L., & Blasingame, T. A. (2011). Reservoir engineering for unconventional gas reservoirs: what do we have to consider. In Paper SPE145080 presented at SPE North American unconventional gas conference and exhibition held in The Woodlands, Texas, USA, 14–6. https://doi.org/10.2118/145080-MS.
- Coates, G. R., Gardner, J. S., & Miller, D. L. (1994). Applying pulse-echo NMR to shaly sand formation evaluation. In SPWLA 35th annual logging symposium, 19–22 June, Tulsa, Oklahoma. https://www.onepetro.org/conference-paper/SPWLA-1994-B.
- Coates, G. R., Marschall, D., Mardon, D., & Galford, J. (1997). A new characterization of bulk-volume irreducible using magnetic resonance. Log Analyst, 39(1), 51–63.Google Scholar
- Coates, G., Xiao, L., & Prammer, M. (1999). NMR logging principles and applications. Houston: Halliburton Energy Services.Google Scholar
- Dastidar, R., Sondergeld, C. H., & Rai, C. S. (2006). NMR desaturation and surface relaxivity measurements on clastics rocks. In SPE-99629-MS presented at SPE Europe/EAGE annual conference and exhibition, Vienna, Austria, June 12–15, 2006. https://doi.org/10.2118/99629-MS.
- Didar, B. R., & Akkutlu, I. Y. (2013). Pore-size dependence of fluid phase behavior and the impact on shale gas reserves. In SPE/AAPG/SEG Unconventional resources technology conference, 12–14 August, Denver, Colorado, USA. https://doi.org/10.15530/URTEC-1624453-MS.
- Feng, S., Niu, X., Liu, F., Yang, X., Liu, X., & You, Y. (2013). Characteristics of Chang7 tight oil reservoir space in Ordos basin and its significance. Zhongnan Daxue Xuebao, 44(11), 4574–4580.Google Scholar
- Fu, J., Luo, A., Zhang, N., Zhang, N., Deng, X., Lv, J., et al. (2014). Determine lower limits of physical properties of effective reservoirs in Chang 7 oil formation in Ordos Basin. China Petroleum Exploration, 19(6), 82–88.Google Scholar
- Han, W., Gao, C., & Han, X. (2015). Application of NMR and micrometer and nanometer CT technology in research of tight reservoir: Taking Chang 7 Member in Ordos Basin as an example. Fault-Block Oil and Gas Field, 25(1), 62–66.Google Scholar
- Hodgkins, M. A., & Howards, J. J. (1999). Application of NMR logging to reservoir characterization of low-resistivity sands in the Gulf of Mexico. AAPG Bulletin, 83(1), 114–127.Google Scholar
- Jia, C., Zou, C., Li, J., Li, D., & Zheng, M. (2012). Assessment criteria, main types, basic features and resource prospects of the tight oil in China. Acta Petrolei Sinica, 33(3), 343–350.Google Scholar
- Kenyon, W. E. (1997). Petrophysical principles of applications of NMR logging. Log Analyst, 38(2), 21–40.Google Scholar
- Kou, R., Alafnan, S. F. K., & Akkutlu, I. Y. (2016). Coupling of Darcy’s equation with molecular transport and its application to upscaling Kerogen permeability. In SPE EUROPEC Featured at EAGE conference and exhibition.Google Scholar
- Li, C. Z., Liu, G. D., Cao, Z., Niu, Z. C., Niu, X. B., & Wang, P. (2016). The study of Chang 7 tight sandstone micro pore characteristics in Longdong area. Ordos Basin. Natural Gas Geoscience, 27(7), 1235–1247.Google Scholar
- Liao, J., Zhu, X., Deng, X., Sun, B., & Hui, X. (2013). Sedimentary characteristics and model of gravity flow in Triassic Yanchang Formation of Longdong Area in Ordos Basin. Earth Science Frontiers, 20(2), 29–39.Google Scholar
- Padhy, G. S., Lemaire, C., Amirtharaj, E. S., & Ioannidis, M. A. (2007). Pore size distribution in multiscale porous media as revealed by DDIF–NMR, mercury porosimetry and statistical image analysis. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 300, 222–234.CrossRefGoogle Scholar
- Pittman, E. D. (1992). Relationship of porosity and permeability to various parameters derived from Mercury Injection Capillary Pressure curves for sandstones. AAPG Bulletin, 76(2), 191–198.Google Scholar
- Schmitt, M., Fernandes, C. P., Wolf, F. G., Neto, J. A. B. D. C., Rahner, C. P., & Santos, V. S. S. D. (2015). Characterization of Brazilian tight gas sandstones relating permeability and angstrom-to micron-scale pore structures. Journal of Natural Gas Science and Engineering, 27, 785–807.CrossRefGoogle Scholar
- Surdam, R. C., Crossey, L. J., Hagen, E. S., & Heasler, H. P. (1989). Organic-inorganic and sandstone diagenesis. AAPG Bulletin, 73(1), 1–23.Google Scholar
- SY/T 6490-2014. (2014). Standards of the petroleum and natural gas industry of the People’s Republic of China. Specification for measurement of rock NMR parameter in laboratory (in Chinese).Google Scholar
- Taktak, F., Rigane, A., Boufares, T., Kharbachi, S., & Bouaziz, S. (2011). Modelling approaches for the estimation of irreducible water saturation and heterogeneities of the commercial Ashtart reservoir from the Gulf of Gabès, Tunisia. Journal of Petroleum Science and Engineering, 78(2), 376–383.CrossRefGoogle Scholar
- Timur, A. (1968). An investigation of permeability, porosity, & residual water saturation relationships for sandstone reservoirs. The Log Analyst, 9(4), 8–17.Google Scholar
- Timur, A. (1972). Nuclear magnetic resonance study of carbonate rocks. Log Analyst, 13(5), 3–11.Google Scholar
- Wang, C., Wang, Q., Chen, G., He, L., Xu, Y., Chen, L., et al. (2017). Petrographic and geochemical characteristics of the lacustrine black shales from the Upper Triassic Yanchang Formation of the Ordos Basin, China: Implications for the organic matter accumulation. Marine and Petroleum Geology, 86, 52–65.CrossRefGoogle Scholar
- Xiao, L., Xie, R., & Liao, G. (2012). NMR logging principles and applications of complex hydrocarbon reservoirs in China. Beijing: Science Press.Google Scholar
- Xie, D., Guo, Y., & Zhao, D. (2014). Fractal characteristics of adsorption pore of shale based on low temperature nitrogen experiment. Journal of China Coal Society, 39(12), 2466–2472.Google Scholar
- Yang, J. (2002). Tectonic evolution and oil–gas reservoirs distribution in Ordos Basin. Beijing: Petroleum Industry Press.Google Scholar
- Yang, H., Dou, W., Liu, X., & Zhang, C. (2010). Analysis on sedimentary facies of Member 7 in Yanchang Formation of Triassic in Ordos Basin. Acta Sedimentologica Sinica, 28(2), 254–263.Google Scholar
- Yang, C., Zhang, J., Wang, X., Tang, X., Chen, Y., Jiang, L., et al. (2017b). Nanoscale pore structure and fractal characteristics of a marine-continental transitional shale: A case study from the lower Permian Shanxi Shale in the southeastern Ordos Basin, China. Marine and Petroleum Geology, 88, 54–68.CrossRefGoogle Scholar
- Yang, H., Zhong, D., Yao, J., Liu, X., Ma, S., & Fan, L. (2013). Pore genetic types and their controlling factors in sandstone reservoir of Yanchang formation in Longdong area, Ordos basin. Earth Science Frontiers, 20(2), 69–76.Google Scholar
- Yu, J., Ma, J., Lu, J., Cao, Y., Feng, S., & Li, W. (2015). Application of mercury injection and rate-controlled mercury penetration in quantitative characterization of microscopic pore structure of tight reservoirs: A case study of the Chang7 reservoir in Huachi-Heshui area, the Ordos Basin. Petroleum Geology and Experiment, 37(6), 789–795.Google Scholar
- Zhu, H., Zhong, D., Yao, J., Niu, X., Liang, X., & Zhao, Y. (2014). Microscopic characteristics and formation mechanism of Upper Triassic Chang 7 tight oil reservoir in the southwest Ordos basin. Journal of China University of Mining and Technology, 43(5), 853–863.Google Scholar