Analyzing the mid-low porosity sandstone dry frame in central Sichuan based on effective medium theory
Yan Xin-Fei1,2, Yao Feng-Chang1,2, Cao Hong1,2, Ba Jing1,2, Hu Lian-Lian3, and Yang Zhi-Fang1,2
1. Research Institute of Petroleum Exploration and Development, Beijing 100083, China.
2. Key Laboratory of Geophysics, PetroChina, Beijing 100083, China.
3. China University of Geosciences (Beijing), Beijing 100083, China.
Abstract Tight gas sandstone reservoirs in Guang’an are characterized by wide distribution and low abundance. Sandstone samples from this area usually have low porosity and poor connectivity. We analyze the observed velocity data of tight sandstone samples with the Mori-Tanaka model, and give the sandstone framework physical model in this area based on theory and experiment analysis. The matrix modulus was obtained by an empirical relationship and then the experiment data were compared with the values predicted by the Mori-Tanaka model with different pore shapes. The results revealed that the experiment data were close to the model with low pore aspect ratio. Considering the matrix modulus and pore shape variation, we find that, under the condition of small mineral composition change, the effective pore aspect ratio of these samples increased with porosity evidently.
This research is supported by the National Natural Foundation of China (No. 41104066), the Basic Research Programs of CNPC during the 12th Five-Year Plan Period (No. 2011A-3601), the Major State Basic Research Development Program of China (No. 2007CB209505), and RIPED Young Innovation Foundation (No. 2010-A-26-01).
About author: Yan Xin-Fei received his MS degree from China University of Geoscience (Beijing) in 2006. Now he is studying for his PhD degree in geophysical prospecting and information technology at the Research Institute of Petroleum Exploration and Development. His current research interests include AVO hydrocarbon detection, and rock physics experiments and applications.
Cite this article:
. Analyzing the mid-low porosity sandstone dry frame in central Sichuan based on effective medium theory[J]. APPLIED GEOPHYSICS, 2011, 8(3): 163-170.
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