A study on the fluid identification method of acidic volcanic reservoirs based on the pore structure

作者：Qin Hao^*; Li Hong Juan; Yang Xue Feng; Wang Chun Yan

来源：Chinese Journal of Geophysics, 2011, 54(2): 422-427.

DOI：10.3969/j.issn.0001-5733.2011.02.019

• Acidic volcanic reservoir
• Fluid identification method
• Porosity combination
• The ratio of transverse wave and longitudinal wave
• Nuclear magnetic resonance
• Integrated parameter
• The ratio of pore radius and throat radius

Because of various types of minerals, complex pore structure and generally high resistivity of volcanic reservoir, using conventional neutron-density-logging curve intersection and high-low of resistivity to identify reservoir fluid type is not viable. Through the analysis of characteristics of natural gas logging response, the paper uses porosity combination, the ratio of transverse wave and longitudinal wave, nuclear magnetic resonance and integrated parameter to identify fluid type. Results show that these methods can only identify gas-bearing reservoir, and the result of identifying reservoirs which contain gas and water is not good. Resistivity is sensitive to the changing of reservoir fluid types, but is not so for acid volcanic reservoir. Starting from the microscopic pore structure of reservoir, the paper studies the influence factors of volcanic reservoir resistivity. Results show that complicated pore structure is one of the reasons of high resistivity of acidic volcanic reservoir. On this basis, the paper develops the fluid type gradual identification method based on the pore structure. Using this method, the paper identified the fluid type of 49 wells in Xushen gas field. Through the test of 69 layers, identification accuracy is 94.1%. The accuracy has increased nearly 15 percent.

• 出版日期2011-2
• 单位大庆油田有限责任公司勘探开发研究院