A formation pressure prediction method based on tectonic overpressure
Shen Bo1,2, Zhang Chao-Mo3, Mao Zhi-Qiang1,2, and Xiao Cheng-Wen4
1. College of Geophysics and Information Engineering, China University of Petroleum, Beijing 102249, China.
2. Key Laboratory of Earth Prospecting and Information Technology, Beijing 102249, China.
3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Jingzhou 434023, Hubei, China.
4. Tarim Petroleum Exploration & Development Company, Korla 841000, Xinjiang, China.
Abstract Traditional formation pressure prediction methods all are based on the formation undercompaction mechanism and the prediction results are obviously low when predicting abnormally high pressure caused by compressional structure overpressure. To eliminate this problem, we propose a new formation pressure prediction method considering compressional structure overpressure as the dominant factor causing abnormally high pressure. First, we establish a model for predicting maximum principal stress, this virtual maximum principal stress is calculated by a double stress field analysis. Then we predict the formation pressure by fitting the maximum principal stress with formation pressure. The real maximum principal stress can be determined by caculating the sum of the virtual maximum principal stresses. Practical application to real data from the A1 and A2 wells in the A gas field shows that this new method has higher accuracy than the traditional equivalent depth method.
This work was sponsored by a grant from the National Key Technologies R & D Program of China during the 9th Five-Year Plan Period (Grant No.9911010102).
Cite this article:
SHEN Bo,ZHANG Chao-Mo,MAO Zhi-Qiang et al. A formation pressure prediction method based on tectonic overpressure[J]. APPLIED GEOPHYSICS, 2010, 7(4): 376-383.
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