We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
基于声学特性的致密砂岩储层含气性评价 .
- Authors
周彦球; 王贵文; 江程舟; 刘秉昌; 解宇强; 赖 强; 夏小勇
- Abstract
Taking Shaximiao Formation in Jinhua-Zhongtaishan area of Sichuan Basin as a case, this paper makes a study on the application of acoustic characteristics of tight sandstone reservoirs in gas-bearing identification, saturation calculation and productivity prediction. Through an acoustic experiment of variable saturations of 30 rock samples, the variation laws of P- and S- wave slowness and the velocity ratio with porosity and water saturation are analyzed, and a locally enhanced acoustic velocity chart and its linear discriminant boundary are formed, and then a piecewise saturation model is established. Verified by the gas test data, the improved velocity chart can effectively identify type Ⅰ and Ⅱ gas reservoirs, with a coincidence rate of 87.5%;the saturation model based on the experiment requires only a few logs as input items, which is simple and easy, and the calculated water saturation is in good agreement with core analysis. On this basis, the “cumulative gas bearing thickness” of the reservoir is calculated by numerical integration, and combined with the gas test data, the productivity prediction models of vertical and horizontal well section are established respectively, with determination coefficients of 0.83 and 0.67, respectively, which can effectively guide the productivity prediction in the study area. The acoustic saturation model based on Gassmann equation is also analyzed and compared. This kind of model is found to require more theoretical parameters and has a greater uncertainty and pseudo boundary effect. Its poor applicability is proved by both the experiment and logging data.
- Publication
Natural Gas Geoscience, 2022, Vol 33, Issue 5, p831
- ISSN
1672-1926
- Publication type
Article
- DOI
10.11764/j.issn.1672-1926.2021.12.003