Low Resistivity Contrast Gas Bearing Formation Identification from Conventional Logs in Tight Gas Sandstones

LIU Xiaopeng, HU Xiaoxin, ZHANG Xiaoling

Abstract


It’s a great challenge in identifying gas bearing formation from conventional logs in tight gas sandstones due to the low resistivity contrast caused by high irreducible water saturation. Based on the difference of the principles of three kinds of porosity logs (density, neutron and acoustic logs), three porosities difference method, three porosities ratio method, correlation of neutron and density logs and the overlap method of water-filled porosity and total porosity are introduced to identify tight gas bearing reservoirs. In gas bearing formations, the difference of three porosities is higher than 0.0, the ratio of three porosities is higher than 1.0, the correlation between density and neutron logs is negative, and the water filled porosities are lower than total porosities. On the contrary, in water saturated formations, the difference of three porosities is lower than 0.0, the ratio of three porosities is lower than 1.0, the correlation between density and neutron logs is positive, and the water filled porosities are overlapped with total porosities. Considering the complexity of in-suit formation, when the proposed identification criterion are mainly meet, the pore fluid should be determined, field examples show that the proposed techniques are applicable in tight gas formation identification.

Key words: Low resistivity contrast gas bearing formation; Tight gas sandstones;  Identification; Difference of three porosities; Ratio of three porosities; Correlation of neutron and density logs


Keywords


Low resistivity contrast gas bearing formation; Tight gas sandstones; Identification; Difference of three porosities; Ratio of three porosities; Correlation of neutron and density logs

Full Text:

PDF

References


[1] Tang, W., Liu, X. P., Hu, X. X., Zhang, X. L., & Wang, S. X. (2013). The Correlation of Neutron and Density Logs and Its Application in Tight Gas Reservoirs Identification. SPE163951.

[2] Ouyang, J., Mao, Z. Q., Xiu, L. J., Shi, Y. J., & Li, C. X. (2009). Genetic Mechanism for Low Contrast Hydrocarbon Bearing Reservoirs and Well Log Evaluation Method. Beijing: Petroleum Industry Press.

[3] Xiao, L., Mao, Z. Q., Dou, W. T., Hou, Y. T., & Jin, Y. (2012). Types and Genesis of Low Contrast Hydrocarbon Reservoirs in Low Permeability Sandstones. Special Oil & Gas Reservoirs, 19(1), 42-46.

[4] Gao, C. Q., Zhong, X. S., Yuan, X. D., Yu, S. Y., & Jiang, W. (1999). Identifying Gas Reservoir with Lower Resistivity from Logging Information. Journal of Jianghan Petroleum Institute, 21(4), 15-17.

[5] Mao,Z. Q. (2012). The Physical Dependence and the Correlation Characteristics of Density and Neutron Logs. Petrophysics, 42(5), 438-443.




DOI: http://dx.doi.org/10.3968%2Fj.aped.1925543820130501.1088

Refbacks

  • There are currently no refbacks.


Reminder

If you have already registered in Journal A and plan to submit article(s) to Journal B, please click the CATEGORIES, or JOURNALS A-Z on the right side of the "HOME".

We only use three mailboxes as follows to deal with issues about paper acceptance, payment and submission of electronic versions of our journals to databases:
caooc@hotmail.com; aped@cscanada.net; aped@cscanada.org

Copyright © 2010 Canadian Research & Development Centre of Sciences and Cultures
Address: 730, 77e AV, Laval, Quebec, H7V 4A8, Canada

Telephone: 1-514-558 6138
Http://www.cscanada.net
Http://www.cscanada.org
E-mail:office@cscanada.net  office@cscanada.org