Contributions of pore-throat size distribution to reservoir quality and fluid distribution from NMR and MIP in tight sandy conglomerate reservoirs

  • Meng ChenEmail author
  • Jiacai Dai
  • Xiangjun Liu
  • Yan Kuang
  • Minjun Qin
  • Zhongtao Wang
Original Paper


Overall pore-throat size distribution is a critical foundation for evaluating tight sandy conglomerate reservoirs. However, the pore-throat size cannot be easily obtained from a single technic due to the complex microstructure. In this paper, a new method was introduced to characterize the microstructure by combining thin sections, scanning electron microscopy (SEM), pressure-controlled injected mercury (PMI), rate-controlled injected mercury (RMI), and nuclear magnetic resonance (NMR). Twenty-four tight sandy conglomerate cores from the Baikouquan Formation of the Mabei oil field, northwest China, were selected to conduct the series of experiments. Overall pore-throat size distribution (TRD) was reconstructed by combining mercury injection porosimetry (MIP) with NMR with pores that were equivalent to triangular cross-section; the radii of the inscribed spheres were obtained to weaken the influence of irregular shapes by RMI. Irreducible water saturation of the cores was achieved by nitrogen displacement, which decreases with increasing of micropore proportion. An ideal relationship between permeability, movable water saturation, and micropore percentages was constructed which indicates the effect of microstructure on reservoir quality and fluid distribution in tight sandy conglomerate reservoirs.


Tight sandy conglomerate reservoirs Mercury injection porosimetry Nuclear magnetic resonance Overall pore-throat size Permeability Fluid distribution 



The authors would like to thank the help from the Xinjiang Oilfield Company, CNPC.

Funding information

This project was supported by the National Natural Science Foundation of China (No. 41804141) and the Chinese Postdoctoral Science Foundation (NO.2018M643525). And this work was also supported by the Scientific Research and Technology Development Project of CNPC (No. 2016D-3802) and the National Key Basic Research Program of China (973 Program) (No. 2015CB250902).


  1. Chen M, Li M, Zhao JZ, Kuang Y (2018a) Irreducible water distribution from nuclear magnetic resonance and constant-rate mercury injection methods in tight oil reservoirs. Int J Oil, Gas Coal Technol 17(4):443–457CrossRefGoogle Scholar
  2. Chen M, Dai JC, Liu XJ, Qin MJ, Pei Y, Wang ZT (2018b) Differences in the Fluid Characteristics between Spontaneous Imbibition and Drainage in Tight Sandstone Cores from Nuclear Magnetic Resonance. Energy & Fuels 32 (10):10333–10343Google Scholar
  3. Clarkson CR, Jensen JL, Blasingame TA (2011) Reservoir engineering for unconventional gas reservoirs: what do we have to consider? SPE 1–45Google Scholar
  4. Clarkson CR, Solano N, Bustin RM, Bustin AMM, Chalmers GRL, He L, Melnichenko YB, Radliński AP, Blach TP (2013) Pore structure characterization of North American shale gas reservoirs using USANS/SANS, gas adsorption, and mercury intrusion. Fuel 103(1):606–616CrossRefGoogle Scholar
  5. Ghanizadeh A, Clarkson CR, Aquino S, Ardakani OH, Sanei H (2015) Petrophysical and geomechanical characteristics of Canadian tight oil and liquid-rich gas reservoirs: II. Geomechanical property estimation. Fuel 153(1):682–691CrossRefGoogle Scholar
  6. Jorand R, Fehr A, Koch A, Clauser C (2011) Study of the variation of thermal conductivity with water saturation using nuclear magnetic resonance. J Geophys Res Solid Earth 116(B8):4684–4698CrossRefGoogle Scholar
  7. Kampschulte M, Langheinirch AC, Sender J, Litzlbauer HD, Althöhn U, Schwab JD, Alejandre-Lafont E, Martels G, Krombach GA (2016) Nano-computed tomography: technique and applications, Fortschr. Rontgenstrasse 188(2):146–154Google Scholar
  8. Klaver J, Desbois G, Urai JL, Littke R (2012) BIB-SEM study of the pore space morphology in early mature Posidonia Shale from the Hils area, Germany. Int J Coal Geol 103(23):12–25CrossRefGoogle Scholar
  9. Leng ZP, Lv WF, Ma DS, Liu QJ, Jia NH, Li T, Jin X, Li DY (2015) Characterization of pore structure in tight oil reservoir rock, SPE 1–8Google Scholar
  10. Loucks RG, Reed RM, Ruppel SC, Hammes U (2012) Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores. AAPG Bull 96(6):1071–1098CrossRefGoogle Scholar
  11. Mayo S, Josh M, Nesterets Y, Esteban L, Pervukhina M, Clennel MB, Maksimenko A, Hall C (2015) Quantitative micro-porosity characterization using synchrotron micro-CT and xenon K-edge subtraction in sandstones, carbonates, shales and coal. Fuel 154:167–173CrossRefGoogle Scholar
  12. Neasham JW (1986) Applications of scanning electron microscopy to characterization and evaluation of reservoir rocks. Am Assoc Pet Geol Bull 70(5):15–18Google Scholar
  13. Qiao J, Zeng J, Yang Z, Feng X, Yao JL, Luo AX (2015) The Nano-macro pore network and the characteristics of petroleum migration and accumulation in Chang 8 tight sandstone reservoir in Heshui, Ordos Basin. Acta Geol Sin (Eng Ed) 89(S1):207–209CrossRefGoogle Scholar
  14. Rouquerol J, Avnir D, Fairbridge CD, Everett DH, Haynes JH, Pernicone N, Ramsay JDF, Sing KSW, Unger KK (1994) Guidelines for the characterization of porous solids. Pure Appl Chem 66(8):1739–1758CrossRefGoogle Scholar
  15. Schmitt M, Fernandes CP, Neto JABDC, Wolf FG, Dos Santos VSS (2013) Characterization of pore systems in seal rocks using nitrogen gas adsorption combined with mercury injection capillary pressure techniques. Mar Pet Geol 39(1):138–149CrossRefGoogle Scholar
  16. Tinni A, Odusina E, Sulucarnain I, Sondergeld C, Rai CS (2015) Nuclear-magnetic-resonance response of brine, oil, and methane in organic-rich shales. SPE Reserv Eval Eng 18(3):400–406Google Scholar
  17. Volokitin Y, Looyestijn WJ, Slijkerman WFJ, Hofman JP (2001) A practical approach to obtain primary drainage capillary pressure curves from NMR core and log data. Petrophysics 42(4):334–343Google Scholar
  18. Wang C, Li T, Gao H, Zhao JS, Li HA (2017) Effect of asphaltene precipitation on CO2-flooding performance in low-permeability sandstones: a nuclear magnetic resonance study. RSC Adv 7(61):38367–38376CrossRefGoogle Scholar
  19. Washburn EW (1921) The dynamics of capillary how. Phys Rev Lett 17(3):273–283Google Scholar
  20. Xi K, Cao Y, Haile BG, Zhu RK, Jahren J, Bjørlykke K, Zhang XX, Hellevang H (2016) How does the pore-throat size control the reservoir quality and oiliness of tight sandstones? The case of the lower Cretaceous Quantou formation in the southern Songliao Basin, China. Mar Pet Geol 76:1–15CrossRefGoogle Scholar
  21. Xiao L, Mao ZQ, Wang ZN, Jin Y (2012) Application of NMR logs in tight gas reservoirs for formation evaluation: a case study of Sichuan basin in China. J Pet Sci Eng 81(2):182–195CrossRefGoogle Scholar
  22. Xiao DS, Lu SF, Lu ZY, Huang W, Gu MW (2016a) Combining nuclear magnetic resonance and rate-controlled porosimetry to probe the pore-throat structure of tight sandstones. Pet Exp Dev 43(6):1049–1059CrossRefGoogle Scholar
  23. Xiao L, Wang H, Zou CC, Mao ZQ, Guo HP (2016b) Improvements on "Application of NMR logs in tight gas reservoirs for formation evaluation: a case study of Sichuan basin in China". J Pet Sci Eng 138(2):11–17Google Scholar
  24. Yao Y, Liu D (2012) Comparison of low-field NMR and mercury intrusion porosimetry in characterizing pore size distributions of coals. Fuel 95:152–158CrossRefGoogle Scholar
  25. Yao YB, Liu DM, Che Y, Tang DZ, Tang SH, Huang WH (2010) Petrophysical characterization of coals by low-field nuclear magnetic resonance (NMR). Fuel 89(7):1371–1380CrossRefGoogle Scholar
  26. Yuan HH (1991) Advances in apex technology: determination of cementation exponent and absolute permeability. Log Anal 32(5):557–570Google Scholar
  27. Yuan HH, Swanson BF (1989) Resolving pore-space characteristics by rate-controlled porosimetry. SPE Form Eval 4(1):17–24CrossRefGoogle Scholar
  28. Zhao H, Ning Z, Wang Q, Zhang R, Zhao TY, Niu TF, Zeng Y (2015) Petrophysical characterization of tight oil reservoirs using pressure-controlled porosimetry combined with rate-controlled porosimetry. Fuel 154:233–242CrossRefGoogle Scholar
  29. Zou CN (2017) Unconventional petroleum geology. Part III: unconventional petroleum miscellany. Chapter 9-tight oil and gas, Petroleum Industry Press, pp 239–273Google Scholar

Copyright information

© Saudi Society for Geosciences 2018

Authors and Affiliations

  1. 1.School of Geoscience and TechnologySouthwest Petroleum UniversityChengduChina
  2. 2.Production Logging Center, China Petroleum Logging Co. Ltd.Xi’anChina

Personalised recommendations