Irreducible Water Saturation Measurement of Volcanic Rocks Using Nuclear Magnetic Resonance

Abstract:

Irreducible water saturation is one of the fundamental parameters in characterizing reservoir formations, and determined as the key factor in reserve calculation and fluid type identification. Measurement on whole core must be taken to analyze irreducible water saturation of volcanic rocks as a result of lithological diversity, porous structure complexity and strong heterogeneity. A new testing method for whole core is proposed by combining Nuclear Magnetic Resonance and centrifugal tests. This new method measures irreducible water saturation using T2 spectrum of whole core demarcated by T2 cutoff measured on 25mm or 38mm diameter core samples which drilled from the whole core. The new method solved the size and shape restricts, long test cycles and viscous fingering defects of conventional methods. According to the comparison with conventional method, the results of the new method coincide well on homogeneous rocks, and are more accuracy with fractured samples.

• Periodical: Advanced Materials Research (Volume 346)
• Pages: 852-857
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.346.852
• Online since: September 2011
• Authors: Yu Zhou, He Kun Guo, Guo Qi Wei
• Keywords: Centrifugal Tests, Irreducible Water Saturation, Nuclear Magnetic Resonance, T2 Cutoff, Volcanic Rock

References

[1] Z. Zhang and B. Wu, Research of the current situation and exploration technology of volcanic reservoir domestic and abroad, Natural Gas Exploration & Development, China, 1994, vol. 16, no. 1, pp.1-26.

[2] C. Wang, H. Shao, and S. Hong, Study of the volcanic rocks and conglomerate reservoir of well Xushen 1, Petroleum Geology & Oilfield Development in Daqing, China, 2003, vol. 22, no. 5, pp.1-4.

[3] S. Lai, X. Han, W. Qu, and L. Wang, The prospects for petroleum exploration of carboniferous in Sannan-Dishuiquan sag and adjacent areas in Junggar basin, Xinjiang Petroleum Geology, China, 2009, vol. 30, no. 3, pp.297-299.

[4] LP. Dake, Fundamentals of reservoir engineering (developments in petroleum science), Elsevier Science, (1998).

[5] P. Nick, R. M, and L. F. Koederitz. A unified theory on residual oil saturation and irreducible water saturation, SPE 77545, (2002).

DOI: 10.2118/77545-ms

[6] D. Tiab and E.C. Donaldson, Petrophysics, 2nd ed., Elsevier, 2004, pp.65-67.

[7] G. M. Homsy, Viscous fingering in porous media, Annual Review of Fluid Mechanics, vol. 19, pp.271-311, January (1987).

DOI: 10.1146/annurev.fl.19.010187.001415

[8] W. E. Kenyon, Nuclear magnetic resonance as a petrophysical measurement, Nuclear Geophysics, 1992, vol. 6, no. 2, pp.153-171.

[9] K. J. Dunn and D. J. Bergman, Nuclear magnetic resonance –petrophysical and logging applications, Elsevier, 2002, pp.101-105.

[10] C. Straley, D. Rossini, H. J. Vinegar, P. N. Tutunjian and C. E. Morriss, Core analysis by low-field NMR, The Log Analyst, 1997, vol. 38, pp.84-94.

[11] J. Feng, Y. Sun, A method to determine T_2 cutoff value in nuclear magnetic resonance log, China Offshore Oil and Gas, 2008, vol. 20, no. 3, pp.11-183.