【摘要】 湔江冲洪积扇是成都平原龙门山前冲洪积扇群之一,为研究其地下水化学特征及控制因素,2018年5月现场采集30组地下水水样.利用描述性统计分析、Piper图解、Arc GIS空间分析和离子比例系数等方法,分析研究区地下水化学类型与离子空间分布特征,讨论控制地下水化学演化过程的主要因素与离子的主要来源.冲洪积扇东北部区域多为弱酸性水,占13. 33%,其余呈弱碱性;地下水化学类型有HCO₃·SO₄-Ca、HCO₃-Ca、HCO₃·SO₄-Ca·Mg与HCO₃·SO₄-Ca·Na,均为淡水;主要离子空间变异系数介于0. 22～0. 91,变异性均为中等变异;地下水化学演化过程主要受溶滤作用的控制,人类活动亦有一定的影响,蒸发浓缩、大气降雨以及阳离子交替吸附作用影响效果不甚明显.更多还原

【Abstract】 The Jianjiang alluvial fan is one of the frontal alluvial fan clusters in the Longmen Mountains of the Chengdu Plain. In order to study the groundwater chemical characteristics and controlling factors,we collected 30 groups of groundwater samples on site in May2018. Descriptive statistical analysis,Piper diagrams,Arc GIS spatial analysis,ion-scale coefficients,and other methods were used to analyze the chemical types and ion spatial distribution characteristics. The main factors controlling the chemical evolution processes of the groundwater and the main sources of ions are discussed. The northeast area of the alluvial fan contains mostly weakly acidic waters,accounting for 13. 33%,the rest being weakly alkaline. Groundwater chemical types included HCO₃·SO₄-Ca,HCO₃-Ca,HCO₃·SO₄-Ca·Mg,and HCO₃·SO₄-Ca·Na,and all groundwater was freshwater. The main ion spatial variation coefficient were between 0. 22 and0. 91,and the variability was moderate. The chemical evolution processes of groundwater was mainly controlled by leaching,and human activities have certain influence. The effect of evaporation and concentration,and atmospheric rainfall,and alternating cation adsorption were not obvious.更多还原