贵州省泥盆系地热资源成矿概念模型

Metallogenic conceptual model of devonian geothermal resources in Guizhou Province

贵州省地层自新元古界至第四系均有出露,发育齐全,主要由沉积岩、浅变质沉积岩组成。贵州省内不同地史时期岩相古地理不同,沉积相类型多样,岩性组合复杂。贵州省贵阳市地热资源勘探点主要集中在贵阳北侧及东北郊区域,由于受到岩相古地理差异、地质构造作用影响,各区域内地热资源成矿特征存在差异。通过研究贵州省贵阳市内以泥盆系为热储层地热井的特征模型因子与沉积相、岩相古地理特征之间的规律,建立了区内地热资源成矿概念模型。研究结果表明区内泥盆系中上统岩相以碳酸盐岩为主,可为地热资源的目的热储层;其上覆石炭系下统岩相以碎屑岩为主,具有较好的隔热保温性,可为盖层;共同构成了良好的地热资源成矿条件。

The strata in Guizhou Province are exposed from Neoproterozoic to Quaternary,well developed,and mainly composed of sedimentary rocks and shallow metamorphic sedimentary rocks.In Guizhou Province,the lithofacies and paleogeography are different in geological history periods,with diverse types of sedimentary facies and complex lithological association.The exploration points of geothermal resources in Guiyang,Guizhou Province are mainly concentrated in the north and northeast suburbs of Guiyang.Due to the differences of lithofacies and paleogeography and geological tectonics,differences exist in the metallogenic characteristics of geothermal resources in each region.By studying the law between the characteristic model factors of geothermal wells with Devonian as thermal reservoir and the characteristics of sedimentary facies and lithofacies paleogeography in Guiyang,Guizhou Province,a conceptual model of geothermal resources mineralization in the study area is established.The results show that the middle and upper Devonian lithofacies in the area are mainly carbonate rocks,which can be used as the target thermal reservoir of geothermal resources.The overlying rock facies of the lower carboniferous system is mainly clastic rock,which has good thermal insulation and can be used as a caprock.Together,they constitute good metallogenic conditions for geothermal resources.