Characteristics of the Salinity and Distribution of the Neopaleozoic Formation Water in Ordos Basin
详细信息
- 责任者：Wang Yunsuo (School of Energy Resources ; China University of Geosciences ; Beijing 100083 ; China) ; Xu Huazheng
- 刊名：Acta Petrolei Sinica
- 出版年：2010
- 卷期：31(5)
- 关键词：油田水 ; oil field water ; 矿化度 ; degree of mineralization ; 深盆气 ; deep-basin gas ; 鄂尔多斯盆地 ; Ordos Basin
- 页码：p.748-753,761
- 图表：3 illus., 4 tables, 10 refs.
- 分类号：1003
- issnNo：ISSN0253-2697
- isbnNo：CN11-2128/TE
摘要
The Neopaleozoic Formation water in the Ordos Basin is mainly distributed in updip reservoir beds on the margin of the basin and characterized by high salinity (>40000mg/L), while the downdip beds are largely full of gas associated with a little formation water that has low salinity and was encountered in several drills. The present study suggested that it was the phase state transform that caused the decrease of formation water salinity. During the formation of the deep-basin gas, the gradually elevated paleotemperature resulted in not only the decrease of formation water solubility but also a complete depletion in cationic ions for the formation water as it vapored into a gas. At the same time,vast amounts of gas were generated from coal beds and all the natural gases together further diluted, dissolved and diffused the "vapored" water, leading to the accumulation of deep-basin gas without water.