A method to determine nuclear magnetic resonance T 2cutoff by fractal analysis
Source abstract
Abstract
T 2cutoff is a key parameter in nuclear magnetic resonance (NMR) application. Its accuracy will directly affect the accuracy of movable fluid volume and bound fluid volume, and indirectly affect the accuracy of bound water saturation (Swi) and permeability. Most of the existing methods need to rely on two or more input parameters to determine T2cutoff, which will affect the application efficiency of NMR for most oil and gas fields under development. In this study, NMR experiments were carried out on a total of 40 core samples. Based on the fractal theory, it is found that there is a good correlation between the fractal dimension of movable fluid (DMFFI) and the geometric mean of T2 spectrum (T2gm), and the equation for calculating the fractal dimension using the unique input parameter of T2gm is obtained by fitting. A method for determining the T2cutoff value using dynamic slope comparison is further established. Finally, the proposed method was validated using N-fold cross-validation. The results show that this method can conveniently and effectively determine the T2cutoff value of the reservoir T2 spectrum and can be extended to the efficient evaluation of NMR logging in other oil and gas fields.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: NMR spectroscopy and applications · Hydrocarbon exploration and reservoir analysis · Enhanced Oil Recovery Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Earth Science and Engineering, Shanxi Institute of Technology 1 , Yangquan 045000,
School of Geophysics and Measurement-Control Technology, East China University of Technology 2 , Nanchang 330013,
The Third Geological Exploration Institute of China Metallurgical Geological Bureau 3 , Taiyuan 030032,
Shanxi Second Geological Engineering Exploration Institute Co., Ltd. 4 , Houma 043009,
North China Measurement and Control Company of Sinopec Jingwei Co., Ltd. 5 , Zhengzhou 450007,
Funding
Nature Science Foundation of Shanxi Province · National Nature Science Foundation of China · The Science and Technological Innovation Programs of Higher Education Institutions in Shanxi · The Open Fund of Cultivation Base of Shanxi Key Laboratory of Mining Area Ecological Restoration and Solid Wastes Utilization
References (49)
Show source-provided references
1. Distinguishing carbonate reservoir pore facies with nuclear magnetic resonance measurements10.1007/s11053-007-9035-8 ↗
2. Pore structure evaluation of bioclastic limestone using NMR and HPMI measurements10.1007/s00723-018-1038-6 ↗
3. Pore size distribution from NMR and image based methods: A comparative study10.1016/j.petrol.2019.106321 ↗
4. A novel computational method for determination of water saturation in oil reservoirs using discrete wavelet transform and nuclear magnetic resonance (NMR) T2 log10.1016/j.petrol.2021.108828 ↗
5. A review of the principles and applications of the NMR technique for near-surface characterization10.1007/s10712-014-9304-0 ↗
6. NMR T2 fluids substitution
7. Pore-fluid characterizations and microscopic mechanisms of sedimentary rocks with three-dimensional NMR: Tight sandstone as an example10.1016/j.jngse.2020.103392 ↗
8. New technique for accurate porosity estimation from logging-while-drilling nuclear magnetic resonance data, NGHP-02 expedition, offshore, India10.1016/j.marpetgeo.2018.11.001 ↗
9. Pore structure characteristics and evaluation of lacustrine mixed fine-grained sedimentary rocks: A case study of the Lucaogou Formation in the Malang Sag, Santanghu Basin, Western China10.1016/j.petrol.2021.108545 ↗
10. Some theoretical considerations related to the quantitative evaluation of the physical characteristics of reservoir rock from electrical log data10.2118/950105-g ↗
11. An investigation of permeability, porosity, and residual water saturation relationships for sandstone reservoirs
12. Effective porosity, producible fluid and permeability in carbonates from NMR logging
13. The reservoir parameter calculation method using the nuclear magnetic resonance log data
14. Quantifying fluid distribution and phase connectivity with a simple 3D cubic pore network model constrained by NMR and MICP data10.1016/j.cageo.2013.08.003 ↗
15. Pore structure evaluation of tight reservoirs in the mixed siliciclastic-carbonate sediments using fractal analysis of NMR experiments and logs10.1016/j.marpetgeo.2019.06.038 ↗
16. Influential factors analysis and porosity correction method of nuclear magnetic resonance measurement in igneous rocks10.1016/j.jappgeo.2018.12.023 ↗
17. Flow and structural analysis of sedimentary rocks by core flooding and nuclear magnetic resonance: A review10.1063/5.0036673 ↗
18. Experimental evaluation of reservoir quality in Mesozoic formations of the Perth Basin (Western Australia) by using a laboratory low field Nuclear Magnetic Resonance10.1016/j.marpetgeo.2014.06.010 ↗
19. A review on pore structure characterization in tight sandstones10.1016/j.earscirev.2017.12.003 ↗
20. Fractal analysis of Donghetang sandstones using NMR measurements10.1021/acs.energyfuels.7b03463 ↗
21. On the method of determining T2cutoff value with the T2 spectrum characteristics10.16489/j.issn.1004-1338.2009.05.007 ↗
22. Comparative evaluation of pore structure heterogeneity in low-permeability tight sandstones using different fractal models based on NMR technology: A case study of Benxi formation in the central Ordos Basin10.1021/acs.energyfuels.0c02738 ↗
23. T1/T2 ratio and frequency dependence of NMR relaxation in porous sedimentary rocks10.1006/jcis.1993.1247 ↗
24. Field test of an experimental pulsed nuclear magnetism tool
25. NMR in partially saturated rocks: Laboratory insights on free fluid index and comparison with borehole logs
26. A method to determine nuclear magnetic resonance (NMR) T2cutoff based on normal distribution simulation in tight sandstone reservoirs10.1016/j.fuel.2018.03.178 ↗
27. A new NMR interpretation technique using error minimization with variable T2cutoff
28. Experimental study of T2cutoff values in low-permeability reservoirs
29. A new approach to determine T2cutoff value with integration of NMR, MDT pressure data in TS-V sand of Charali field
30. An evaluation of the application of low field NMR in the characterization of carbonate reservoirs
31. Determination of nuclear magnetic resonance T2cutoff value based on multifractal theory—An application in sandstone with complex pore structure10.1190/geo2014-0140.1 ↗
32. A method to determine nuclear magnetic resonance T2cutoff value of tight sandstone reservoir based on multifractal analysis10.1002/ese3.574 ↗
33. Analytical derivation of Brooks–Corey type capillary pressure models using fractal geometry and evaluation of rock heterogeneity10.1016/j.petrol.2010.05.002 ↗
34. Determining fractal dimension from nuclear magnetic resonance data in rocks with internal magnetic field gradients10.1190/geo2014-0325.1 ↗
35. Fractal dimension of pore-space geometry of an Eocene sandstone formation10.1190/geo2014-0143.1 ↗
36. Estimating irreducible water saturation and permeability of sandstones from nuclear magnetic resonance measurements by fractal analysis10.1016/j.marpetgeo.2019.07.037 ↗
37. The dynamics of capillary flow10.1103/physrev.17.273 ↗
38. Nuclear magnetic resonance surface relaxivity and its advanced application in calculating pore size distributions10.1016/j.marpetgeo.2019.08.002 ↗
39. Fractal characteristics of reservoir rock pore structure based on NMR T2 distribution
40. A practical approach to obtain primary drainage capillary pressure curves from NMR core and log data
41. Investigation on the pore structure and multifractal characteristics of tight oil reservoirs using NMR measurements: Permian Lucaogou Formation in Jimusaer Sag, Junggar Basin10.1016/j.marpetgeo.2017.07.011 ↗
42. Fractal characterization of pores in shales using NMR: A case study from the Lower Cambrian Niutitang Formation in the Middle Yangtze Platform, Southwest China10.1016/j.jngse.2016.09.030 ↗
43. Estimating solutions of first kind integral equations with nonnegative constraints and optimal smoothing10.1137/0718025 ↗
44. A new characterization of bulk-volume irreducible using magnetic resonance
45. Fast NMR logging for bound fluid and permeability
46. Fractal pore structure of sedimentary rocks: Simulation in 2-d using a relaxed bidisperse ballistic deposition model10.1016/j.jappgeo.2012.09.002 ↗
47. Fractal characteristics of shales from a shale gas reservoir in the Sichuan Basin, China10.1016/j.fuel.2013.07.040 ↗
48. Comparison of fractal models using NMR and CT analysis in low permeability sandstones10.1016/j.marpetgeo.2019.104069 ↗
49. NMR logging of natural gas reservoirs