Abstract:
The geothermal field is one of the important geological conditions for mining activities. Based on the data of 332 welltimes borehole temperature measurement, stratigraphic lithology and its combination characteristics, tectonic geology and hydrogeological conditions, the ground temperature and negative anomalies and their main controlling factors in Sijiazhuang minefield are discussed. The results show that the modern geothermal field in Sijiazhuang minefield is controlled by three geological factors such as formation and thermal conductivity, groundwater and open structure. The proportion of formation sandstone is high, its thermal conductivity is strong, the heat conduction is fast and it is not easy to cause local heat accumulation. It is the main controlling factor of the low ground temperature of the field. The strong runoff of regional groundwater is the macroscopic control factor; the groundwater runoff state plays double effect of cooling and inducing the channels for gas dispersion, which is a major controlling factor to the geothermal negative anomaly and geothermal field varies of this minefield. The open extensional fault and collapse column not only provide a good channel for geothermal loss, but also provide favorable conditions for the refrigeration to the surrounding rock from aquifer groundwater circulation and runoff, which is the key control factor to the geothermal negative anomaly and geothermal field varies of this minefield.