Porosity Estimation Based on Petrophysical Model and Prestack Elastic Inversion
详细信息
- 责任者：Cai Hanpeng (Geophysical Exploration Company ; Chuanqing Drilling Engineering Co. ; PetroChina ; Chengdu 610213 ; China) ; He Zhenhua
- 刊名：Natural Gas Industry
- 出版年：2013
- 卷期：33(9)
- 关键词：地震勘探 ; seismic exploration ; 孔隙度 ; porosity
- 页码：p.48-52
- 图表：6 illus., 25 refs.
- 分类号：1600
- issnNo：ISSN1000-0976
- isbnNo：CN51-1179/TE
摘要
Accurate estimation of porosity is critical to reservoir prediction,reservoir characterization,reserves estimation,and comprehensive study of oil/gas reservoirs.However,conventional porosity estimation methods have the shortages of low accuracy and ambiguity of physical meanings.Based on the basic theories of petrophysics and geophysical test data and rational assumptions,a mathematical model was deduced and established by using the Gassmann and Eshelby-Walsh equations.This model can be used to calculate rock porosity through pre-stack elastic inversion of seismic data with high signal-to-noise ratios.Application of this new model to real data shows that it can improve the accuracy of carbonate reservoir porosity estimation by about 10%,and effectively predict the vertical and horizontal distribution of porosity.The vertical resolutions of S-wave velocity and bulk density profiles are higher than those of P-wave velocity profile,and the porosity calculation based on this can improve the vertical resolutions of porosity profile.The porosity data provided by this mathematical model are helpful for drilling planning,reserve estimation and reservoir characterization.