The Hydrogeochemical Characteristics And The Evolution Of Geothermal Water In Guide Area,Qinghai

Geothermal resources are a kind of clean and renewable energy.Studying the evolution laws of geothermal water can better develop and utilize geothermal resources,which is of great significance to solve the increasingly serious ecological and environmental problems.The Guide Basin has very rich geothermal energy resources,such as geothermal water and dry hot rocks.Areas with well-developed dry and hot rocks are often accompanied by the emergence of geothermal water.Understanding the formation and evolution of geothermal water is not only the basis for the development and utilization of geothermal water,but also helps to deepen the understanding of the distribution and genesis of dry and hot rocks.In this paper,the five faults in the Guide Basin are convective geothermal water is the research object.By comprehensively using methods such as Hydrogeochemical analysis and hydrogen and oxygen isotope analysis,the following understandings are obtained:(1)The geothermal water of Qu Naihai and Zhacang Temple at low elevations of fault convection geothermal water has a higher degree of geothermal water interaction than the geothermal water of Xinjie,Lancai and Xibsha at high altitudes high.The deeper the geothermal water buried in the conductive geothermal water in the basin,the higher the degree of water-rock interaction.The type of water chemistry and TDS are related to the degree of water-rock interaction.The degree of water-rock interaction is high.The cations in geothermal water are mainly Na~+and the anions are mainly Cl~-.(2)Based on the traditional geothermometer and the mineral balance method prediction of geothermal reservoir temperatures.The mineral balance method was used to quantify the degree of cold water mixing and degassing.The cold water mixing ratio in the Guide Basin is between 7%~34%,degassing will cause the PH value of geothermal water to rise during the circulation.(3)Hydrogen and oxygen isotopes occur,and geothermal water is the source of atmospheric precipitation.Among them,Xinjie,Lancai and Xibusha geothermal water comes from atmospheric precipitation replenishment when the climate is colder.The reasons that cause the geothermal water in Qu Naihai and Zhacangsi to deviate from the atmospheric precipitation line are water-rock interaction and liquid-vapor separation.The ratio of cold water mixing calculated by the mineral balance method was used to estimate the variation range of hydrogen and oxygen isotopes caused by cold water mixing and liquid-vapor separation.Hydrogen and oxygen isotope composition.The calculation method of the influence of the three processes of water-rock reaction,cold water mixing and water vapor separation on the hydrogen and oxygen isotopes can be used to analyze the cause of the hydrogen and oxygen isotopes of geothermal water in other regions,thereby deepening the understanding of the geothermal water cycle process.