寺家庄井田地温负异常及其主控因素

Negative geothermal anomaly and its main geological controlling factors in Sijiazhuang minefield

地温场是采矿活动的重要地质条件之一。基于332井次钻孔测温数据、地层岩性及其组合特征、构造地质及水文地质条件等,探讨了寺家庄井田地温负异常及其主控因素。结果表明:寺家庄井田现代地温场受地层及热导率、地下水和开放型构造等三大地质因素控制。地层砂岩所占比例较高,其导热性强、热传导快,不易造成局部聚热,是井田地温值整体偏低的主要控制因素,区域地下水的强径流状态是现代地温整体偏低的宏观控制因素;地下水径流状态对围岩温度起到"制冷"和诱发构造通道散失双重控制作用,是研究区地温负异常和地温场分异的重要控制因素,开放型张性较大正断层、陷落柱不但为地温的散失提供了有利通道,亦为邻近含水层间地下水循环、径流对围岩温度的"制冷"提供了有利条件,是井田地温负异常和地温场分异的关键控制因素。

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.