咸阳城区地下热水地球化学演化模拟  

Simulation of Geochemical Evolution of Geothermal Beneath the Xianyang City , Shaanxi Province

作　　者：周鑫[1] 马致远[1] 李婷[1] 豆惠萍[1] 

机构地区：[1]长安大学环境科学与工程学院,陕西西安710054

出　　处：《西北地质》2012年第2期139-145,共7页Northwestern Geology

基　　金：国家自然基金"同位素演化对地压型热储流体起源成因的指示意义"(41172211)

摘　　要：应用水文地球化学模拟(PHREEQC软件)对咸阳城区地下热水进行了水文地球化学演化和路径模拟。模拟路径分别为西、西北两个补给方向。模拟结果表明,沿地下水流向发生了一系列的水-岩反应,西线R5→SP2水化学类型由Na-HCO3-Cl转化为Na-Cl型,而西北线R6→SP2水化学类型由Na-Ca-HCO3-Cl转化为Na-Cl型,在水流路径上SiO2(玉髓)、方解石、白云石和高岭石发生了沉淀,而岩盐、石膏、天青石、钠长石、云母和萤石发生了溶解作用。对研究区地下热水地球化学反应路径模拟,描述了研究区地下热水补给到排泄的演化特征,表明水-岩作用模拟对于揭示研究区地下水化学演化环境具有重要的指示意义。A software for hydrochemical analysis is used to perform the geochemical analysis and flow path simulation of geothermal in Xianyang city. The simulation path directions are respectively west and northwest. The simulation results show that the geothermal water occurred a series of water-rock reaction along the direction of water flow path. The hydrochemistry type of R5-SP2 flow path （western path） changes from Na-HCO3-C1 to Na-C1. Meanwhile, R6-SP2 flow path （northwest path） direction hydrochemistry type changes from Na-Ca-HCOs-C1 to Na-CI. The quartz, calcite, dolomite and kaolinite have been precipitated when the geothermal water traverse the flow path, but halite, gypsum, lazurite, albite and fluorite dissolved. In the study area, the geothermal water reaction path simulation described the geothermal water evolutional characteristics from recharge area to discharge area, which revealed that water-rock reaction simulation for the groundwater chemical evolution environment has important signifi- cance.

关 键 词：地球化学模拟 水岩相互作用 地下热水 水文地球化学 

分 类 号：P64[天文地球—地质矿产勘探]