Oxygen and hydrogen isotope exchange of geopressured thermal water in the central Guanzhong basin

详细信息    查看全文

• 作者：Juan YU ; Zhi-yuan MA ; Zhao-wei WANG ; Wei-liang LI ; Yan SU
• 关键词：Guanzhong basin ; geopressured thermal water ; ¹⁸O shifts
• 刊名：Mining Science and Technology (China)
• 出版年：2009
• 出版时间：January 2009
• 年：2009
• 卷：19
• 期：1
• 页码：115-119
• 全文大小：706 K

文摘

Geothermal water of Xi'an and Xianyang in the central Guanzhong basin is typically geopressured thermal water in China. δ¹⁸O and δD data of geopressured thermal water in Xi'an and Xianyang, combined with data from the perimeter of the basin, are analyzed to study features of hydrogen and oxygen shifts. The results show that ¹⁸O exchange of geothermal water at the perimeter of the basin and in the non-geopressured thermal water in the center of the basin is not evident, while in most of the geopressured thermal water in the central basin, in cities such as Xi'an and Xianyang, significant oxygen exchange had taken place as well as hydrogen exchange, suggesting that isotope exchanges would slowly move the geothermal water system towards equilibrium. Thermal water reservoirs in the central basin have passed through significant water-rock reactions. Moreover, the geothermal reservoir of Xianyang city is relatively much more enclosed than that of Xi'an city. It has been observed that the more enclosed the geological environment of geothermal water is, the more obvious the oxygen shifts are. With the increasing of the depth, residence time, total amounts of dissolute solids and temperatures of geothermal waters, the oxygen exchange accelerates.