天津地热流体水化学特征及同位素分析

Analysis on the hydrochemical characteristics and isotope of geothermal fluid in Tianjin

天津地热流体受区域地质构造、地层岩性、径流强度和径流距离等因素的影响,水化学特征在水平及垂直方向表现出一定的分带性。本文以天津地区大量的地热流体水化学数据为研究对象,发现地热流体的水化学特征与地质构造单元、热储层特征有着较好的相关关系。地热流体稳定同位素资料研究表明:天津地区大规模的开采加强了各热储层之间地热流体的联系程度。地热流体放射性同位素资料研究表明:雾迷山组热储层的大规模开采使更多的深部地热流体上涌,低矿化度的孔隙型地热流体垂向上没有明显的连通。该研究成果可为天津地区地热流体的合理开发利用提供依据。

The geothermal fluid in Tianjin is affected by the regional geological structure,stratigraphic lithology,runoff intensity and runoff distance.The hydrochemical characteristics show a certain zonation both in horizontal and vertical directions.Based on a lot of the geological fluid chemical data,it is found that the chemical characteristics of the geothermal fluid and geological tectonic units,thermal reservoir characteristics have a good correlation;at the same time,stable isotope data of geothermal fluid show that the large-scale mining enhanced the connection of geothermal fluid between the thermal reservoirs;radioactive isotope data of geothermal fluids show that more deep geothermal fluid upwells because of large-scale mining in Wumishan formation of Jixian system and low mineralized pore type geothermal fluid has no obvious connection in vertical direction.The research results can provide the basis for the rational development and utilization of geothermal fluid in Tianjin area.