汝城干热岩地热资源研究

 汝城热水镇出露98℃天然热泉,该地区深部干热岩地热资源相当可观。通过大量钻孔地温测量和大地热流测试等勘探工作,评估了该地区干热岩地热资源的基本情况。勘探结果表明,研究区内平均地温增温梯度为18.7℃/100 m,最高值达35.2℃/100 m,主要高温钻孔的大地热流量介于60~170 MW/m²,地热资源较为可观。该地热田的热源来自深部岩浆余热,热储主要是F₁、F₃断裂带上盘及其他次级断层派生的密集裂隙系统。区内热水河以东花岗岩体为浅部水热热储盖层;热水河以西震旦系的板岩为深部热源盖层。模拟结果表明,研究区地热田热储层下底面温度为260℃,热储层上顶面温度为255℃,热储层以上厚度为3500~4000 m。汝城地区热储埋藏深度较浅,热储温度较高,是较好的干热岩开发靶区。

Hot dry rock geothermal resources in Ru County

Ru County is rich in hot dry rock geothermal resources with a 98℃ hot spring distributed. However, research on the resources is scarce. This study evaluated the hot dry rock geothermal resource in Ru County on the basis of borehole temperature measurement and terrestrial heat flow survey. The results show that the average geothermal gradient was 18.7℃/100 m with a max of 35.2℃/100 m and the heat flow changed between 60 and 170 MW/m². Heat came from the deep magma in the geothermal field. The geothermal reservoir was composed of dense fractures produced by sub-faults in the upper part of F1 fault and F3 fault. The cover of the geothermal reservoir contained exposed granite on the east side of the Reshui River and Sinian slate on the west side. According to our model, the temperature was 260℃ on the lower site and 255℃ on the upper site. The stratum thickness is about 3500-4000 m above the geothermal reservoir. In Ru County, the geothermal reservoir has a shallow burial depth and a high temperature belonging to a suitable destination area of hot dry rock development.