| Title | Migration characteristics of geothermal fluids in karst thermal reservoirs in the Beijing-Tianjin-Hebei Plain |
|---|---|
| Authors | Xiang MAO, Jinxia LIU, Lu LUO |
| Year | 2023 |
| Conference | World Geothermal Congress |
| Keywords | Beijing-Tianjin-Hebei Plain；karst geothermal reservoir；migration characteristic；geothermal fluid；sustainable development |
| Abstract | ABSTRACT The Beijing-Tianjin-Hebei Plain is one of the regions with the largest scale and the fastest growth of medium and deep geothermal heating in China. Based on the test of 82 geothermal fluid samples from 7 geothermal fields in Hebei Province, 2 geothermal fields in Henan and 2 geothermal fields in Shandong Province, and combined with previous studies on the chemical characteristics of karst geothermal water in Beijing and Tianjin, the migration characteristics of geothermal fluids in karst geothermal reservoirs in the Beijing-Tianjin-Hebei Plain were systematically analyzed. Hydrochemical characteristics of karst geothermal water in the research areas show certain differences, the geothermal water in Hebei is more mature than its neighboring provinces. The distribution of total dissolved solids (TDS) and strontium elements in the area is low in the north and south and high in the middle, indicating that the overall flow direction of geothermal fluid is from north-south to the middle. Combined with the groundwater flow field and the change trend of hydrochemical characteristics of geothermal wells along the geological section, a geothermal water migration model is established. The geothermal fluids from Taihang Mountain, Yanshan Mountain and Western Shandong Mountain enter the basin and continue to migrate to the central part of the basin along the water conducting faults. Migration characteristics of the same supply direction are not the same. The geothermal fluids from Taihang Mountain are cut off by Niudong fault in the north and end in the central uplift belt of Jizhong Depression, while in the south it enters the east of Jizhong Depression relatively quickly along the Hengshui conversion belt. The geothermal fluids from Yanshan Mountain migrate into the basin along the Cangdong fault, but the fault also separates the hydraulic connection between the tectonic units. Considering the effective dynamic conditions, it is recommended to further expand the scale of scientific development and utilization of geothermal energy in the geothermal water catchment areas around Xiong County and southwest Cangzhou City. |