| dc.description.abstract | In recent years, urban expansion, increased industrial economic activities, and improved living standards have led to a continuous rise in the demand for related resources. Therefore, it is crucial to conduct effective assessments and develop alternative resources, such as quantifying the available water resources in coastal aquifers to bridge the gap in water demand, providing valuable references for water resource development plans. Regarding electricity demand, geothermal energy presents an environmentally friendly, economical, and efficient method for energy production. The efficiency of heat pumps varies with groundwater levels, temperature, water content, and the thermal transport properties of surrounding soil, making it essential to conduct effective and accurate investigations of hydraulic and thermal conductivity properties. Currently, most methods used for hydrogeological or geothermal environment investigations are unable to estimate features characterized by heterogeneity. The application of the latest technologies allows for high-resolution temperature measurements in both spatial and temporal dimensions, offering advantages for understanding the heterogeneity of porous media and the behavior of heat transfer.
This study explores the use of thermal tracer technology to quantify groundwater flux in aquifers and to infer aquifer parameter distribution based on temperature responses. Additionally, laboratory experiments are conducted to quantitatively analyze the range of influence and efficiency of thermal tracer tests.
The results indicate that maintaining increased injection temperatures correlates with an increased range of impact, while maintaining constant injection rates with increased injection temperatures leads to a gradually diminishing range of influence as temperatures rise. In site-scale tests, thermal tracer tests are employed to evaluate the stratified flux differences caused by the layered structure of coastal aquifers while investigating the interactions between freshwater and seawater and the characteristics of tidal fluctuations. When the tidal conditions rise from low to high, the average groundwater flux is estimated to be 0.5 m/day, with a range of 1.77 to 0.2 m/day during high tide to low tide conditions, and 0.25 to 0.02 m/day when conditions transition from low to high tide. Notably, the vertical distribution of flux shows significant differences, primarily controlled by the properties of the aquifer materials. | en_US |