贵州息烽温泉控热推覆构造的发现及成因研究

根据近年来磷矿深部勘探资料,对贵州息烽温泉的构造地质条件及地热特征开展研究,获得了有关温泉地质成因的新认识。①由洋水背斜、安清断层(F₁)和温泉断层(F₂)组成的叠瓦状逆冲推覆构造体系,构成了息烽温泉地热水系统的主体及边界,该控热构造体系内地表构造与地腹构造并不统一,老地层盖在新地层上,构成顶、底两层叠置的多个热储单元,这些热储单元是地热水形成和运移的良好场所。②安清断层(F₁)使多个热储单元直接接触,从而具有密切的水力联系,为导水、导热的良好通道; 温泉断层(F₂)构成了息烽温泉区地热水系统的边界。③大气降水沿断裂通道下渗至深部的碳酸盐岩热储层中,吸收热量形成地热水,在高温高压条件下,向洋水背斜核部进行迁移,受上覆寒武系碎屑岩盖层的保护和温泉断层的限制,形成洋水背斜西翼和北端的地热资源有利富集区,最后受分支断层阻挡而自然岀露。

Discovery of geothermal nappe structure and genesis research of Xifeng hot spring in Guizhou

Based on the deep exploration data in phosphate ore in recent years, the authors in this research studied the geological conditions and geothermal characteristics of Xifeng hot spring in Guizhou, and put forward new understandings of geological genesis. ① The imbricate thrust-nappe tectonic system is composed of Yangshui Anticline, Anqing Fault(F₁) and Wenquan Fault(F₂), which constitute the main body and boundary of Xifeng hot spring geothermal water system. The surface structure and internal structure of this geothermal structure system is heterogeneous. And the new strata are covered by the old strata, which consist many overlapped thermal storage units, and these thermal storage units become good places for the formation and migration of geothermal water. ② A series of geothermal storage units are directly contacted by Anqing Fault (F₁), and these units have close hydraulic contact, which provides good channel for water and heat. Wenquan Fault (F₂) forms the geothermal water boundary of Xifeng hot spring. ③ The atmospheric precipitation penetrates into the deep carbonate reservoir along the fracture channel, and it becomes geothermal water after the absorption of heat. Under high temperature and high pressure conditions, the geothermal water continuously migrates to the core of Yangshui Anticline, which is preserved by the overlying strata of Cambrian clastic rocks and limited by the hot spring fault. Then the geothermal water forms a favorable geothermal resource enrichment area in the west wing and north end of Yangshui Anticline, and then is blocked by faults and exposed to the surface.