A New Parameter for Gas Reservoir Appraisal: Suffusive Degree
详细信息
- 责任者：Zhao Liangxiao (Geologic Exploration & Development Research Institute ; Chuanqing Drilling Engineering Co. ; Ltd. ; CNPC ; Chengdu 610051 ; China) ; Xing Huimin
- 刊名：Natural Gas Industry
- 出版年：2010
- 卷期：30(6)
- 关键词：天然气 ; natural gas ; 储层评价 ; reservoir evaluation
- 页码：p.31-34
- 图表：4 illus., 2 tables, 4 refs.
- 分类号：1003
- issnNo：ISSN1000-0976
- isbnNo：CN51-1179/TE
摘要
Two problems exist in gas reservoir identification and productivity estimation. One is that a big error occurs when gas layers are identified according to the excavation effect. The other is that gas productivity can not be really determined by those parameters such as porosity, pore structure, permeability, saturation and net thickness, the higher values of which do not mean a higher productivity. A new concept of gas suffusive degree is presented to solve these problems .Based on analysis of the determinative factors of gas suffusive degree and density, the hydrogen index from conventional logging data and the matrix-density-corrected density porosity and its associated chart board are used to calculate the in-situ porosity and the water saturation of wash zones. Then, in-situ gas density is calculated by using density-volume equation. Finally, formation pressure and gas suffusive degree are calculated. The calculation of suffusive degree reveals not only the causes of the above-mentioned two problems but also the positive correlation between suffusive degree and productivity. This parameter can enhance the accuracy of gas reservoir appraisal and help predict gas distribution and the level of enrichment.