Geochemical evidence for the nonexistence of supercritical geothermal fluids at the Yangbajing geothermal field, southern Tibet

Wang，Yingchun1,2; Li，Liang1,3; Wen，Huaguo1,3; Hao，Yinlei4

2022

10.1016/j.jhydrol.2021.127243

JOURNAL OF HYDROLOGY   影响因子和分区

0022-1694

1879-2707

Exploring and exploiting high-temperature (even supercritical) geothermal resources are significant to meet energy demands and reduce carbon emissions. The Yangbajing geothermal field is the most exploited in China, with the currently highest temperature (329.8 °C) measured in a geothermal well. However, whether there are supercritical geothermal fluids beneath the deep parts of this geothermal field is under controversy. In this paper, the water isotope, chemical compositions, and C–He isotopes of gas samples were collected and analyzed. The geothermal water originated from the mixing of meteoric water and magmatic water (25%). The sources of CO in the geothermal field were dominated by the thermogenic degassing of carbonates and metasediments in the crust while the radioactive decay of U and Th in granite is the dominated source of He. The temperatures of three different reservoirs are 150 ± 15 °C, 250 ± 10 °C, and ∼320 °C (with a depth of ∼8 km), respectively. These were obtained using dissolved gas, soil CO flux, and noble gas geothermometers. Unlike other supercritical geothermal fields worldwide with larger, shallower, basaltic magma chambers, the Yangbajing geothermal field has a deep-seated, small-scale, granitic magma chamber. Thus, its geological conditions are not conducive for gestating supercritical fluids. These results are of great significance for exploring and developing high-temperature (even ultra-high-temperature) geothermal resources in China.

Gas geothermometer Geothermal fluid Reservoir temperature Supercritical geothermal fluids Yangbajing geothermal field

SCI ; EI

英语

其他

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology)[PLC2020032] ; National Natural Science Foundation of China[42002300] ; Second Tibetan Plateau Sci-entific Expedition and Research Program[2019QZKK0804]

Engineering ; Geology ; Water Resources

Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources

WOS:000731346800004

ELSEVIER

20215011303189

Carbon dioxide ; Chemical analysis ; Effluent treatment ; Geothermal wells ; Inert gases ; Isotopes ; Supercritical fluids

Industrial Wastes Treatment and Disposal:452.4 ; Geothermal Phenomena:481.3.1 ; Geothermal Energy:615.1 ; Inorganic Compounds:804.2 ; Physical Properties of Gases, Liquids and Solids:931.2

ENGINEERING

2-s2.0-85120695671

Scopus

1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu,610059,China
2.College of Energy Resources,Chengdu University of Technology,Chengdu,610059,China
3.Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu,610059,China
4.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China

Wang，Yingchun,Li，Liang,Wen，Huaguo,et al. Geochemical evidence for the nonexistence of supercritical geothermal fluids at the Yangbajing geothermal field, southern Tibet[J]. JOURNAL OF HYDROLOGY,2022,604.

Wang，Yingchun,Li，Liang,Wen，Huaguo,&Hao，Yinlei.(2022).Geochemical evidence for the nonexistence of supercritical geothermal fluids at the Yangbajing geothermal field, southern Tibet.JOURNAL OF HYDROLOGY,604.

Wang，Yingchun,et al."Geochemical evidence for the nonexistence of supercritical geothermal fluids at the Yangbajing geothermal field, southern Tibet".JOURNAL OF HYDROLOGY 604(2022).