西安 咸阳地下热水氘过量参数研究

西安咸阳地下热水氘过量参数研究

摘要: 通过分析西安、咸阳地区地下热水的δ¹⁸O和δD同位素数据,研究了氘过量参数d的特征及水岩交换程度对d值分布的影响。结果表明:西安、咸阳地区浅层地下热水水岩作用不明显,深层地下热水水岩交换作用显著,发生氧漂移,咸阳部分水点发生较为明显的²H交换;含水层封闭性越好,地质环境越还原,水岩作用就越强,d值就越小;氧漂移愈偏离大气降水线,d值越小,埋深愈大,滞留时间愈长,矿化度愈大,地下热水温度越高。

Abstract: By analyzing the δ¹⁸O and δD isotopic data of Xi'an and Xianyang,this paper studies the features of the deuterium excess(dexcess) parameter in thermal groundwater and the effect of the extent of water-rock exchange on d-excess value distribution,concluding that water-rock exchange of low thermal groundwater in Xi'an and Xianyang is not apparent,while the deep is quite apparent and there is oxygen draft.Deuterium exchange of some samples in Xianyang is also apparent.The more closed the aquifer is,the more reductive the geological environment is.The more intense the water-rock exchange is,the smaller the d-excess is.In addition,as the oxygen draft grows further away from the local mean water line,the d-excess gets smaller,the depth gets deeper,the residence time gets longer,the total dissolute solid gets bigger,the temperature of thermal groundwater gets higher.