贵州省荔波县某地区地热水资源地质条件分析

Analysis on Geological Conditions of Geothermal Water Resources in An Area of Libo County,Guizhou Province

所选工作区位于荔波县县城以南225°方位约23 km处的群峰之中,为查明研究区地热水资源蕴含量,对其开展综合野外地质及地球物理勘查工作。共布设剖面3条,结果表明,区内出露标高在-1200~-2000(埋深-2000~2800 m),地层岩性从上自下形成了有利地热“储集单元”;估算区内地下热矿水温度为62.98℃,预测井口水温(可采水温预测)约44.78℃,预计单井涌水量约400~500 m^(3)/d;其热储单元泥盆系革老河组至独山组pH值7.15~7.35,属中性水,偏硅酸、氟等含量能达到医疗价值浓度或命名矿水浓度标准,水化学类型为HCO_(3)-Ca或HCO_(3)·SO_(4)-Ca·Mg型水,为深部钻探工程布设提供依据,对荔波县旅游规划及可持续发展具有重大意义。

The selected work area is located among the peaks about 23km away from 225°in the south of Libo County.In order to find out the accumulation content of geothermal water resources in the study area,comprehensive field geological and geophysical exploration work is carried out.A total of 3 sections are arranged.The results show that the exposed elevation in the area is-1200~-2000(buried depth-2000~2800m),and the formation lithology forms a favorable geothermal“reservoir unit”from top to bottom.The estimated temperature of underground hot mineral water in the area is 62.98℃,the predicted wellhead water temperature(recoverable water temperature)is about 44.78℃,and the estimated water inflow of single well is about 400~500 m^(3)/d.The pH value of the thermal storage unit from gelaohe formation to Dushan formation of Devonian system is 7.15~7.35.It is neutral water.The contents of metasilicic acid and fluorine can reach the concentration of medical value or the concentration standard of named mineral water.The hydrochemical type is HCO_(3)-Ca or HCO_(3)·SO_(4)-Ca·Mg water,which provides a basis for the layout of deep drilling projects and is of great significance to the tourism planning and sustainable development of Libo County.