摘要
贵州省岩溶山区分布着以石灰岩为主的非均质岩溶地下水和以白云岩为主的均质岩溶地下水。非均质岩溶地下水具有岩溶发育且孤立、赋存分布极不均匀、地下水量大但动态变幅大,地下水资源开采难度大、地下水环境脆弱等特征,影响区内居民正常生活饮水,制约着经济和社会发展。以贵州省黔东北某一地下河系统为研究靶区,为研究该地下河系统的地下水径流特征,在研究区内开展5次连通试验和1次群孔抽水试验,分析地下河系统的地下水径流方向、径流类型、径流动态、径流速度、流态、流线的时空分布特征,对比均匀岩溶含水介质中地下水径流特征的差异。结果表明:研究区内4处落水洞(投放点)均在南南西面S1号地下河出口出流,证明区内地下水径流方向具有上升下降的并存性和地下河管道的集中性;区内地下水径流类型以溶洞-管道、集中径流为主,小规模、侧向支管道补给为辅的汇流型,局部受断层阻水存在缓流现象;地下水径流的动态不稳定性、“快补快排”的季节性较显著;区内地下水流线亦具有不规则上升、下降的“U”型特征,导致区内钻孔揭露地下水位埋深大于静止水位,垂向上的地下水具有承压性。地下河系统石灰岩区岩溶发育具有不均匀性,导致地下水在径流方向、径流类型、流速、动态、流线等与均匀岩溶含水介质的地下水径流特征差异性大、对比性显著。研究结果为指导贵州岩溶山区地下水开发与保护提供参考。
There are heterogeneous karst groundwater mainly limestone and homogeneous karst groundwater mainly dolomite in karst mountainous areas of Guizhou Province.Heterogeneous karst groundwater is characterized by isolated karst development,extremely uneven occurrence and distribution,large underground water volume but large dynamic variation,difficult exploitation of groundwater resources,fragile groundwater environment,etc.,which affects the normal drinking water of residents in the area and restricts economic and social development.Taking an underground river system in northeast Guizhou Province as the research target area,in order to study the groundwater runoff characteristics of this underground river system,five connectivity tests and one group hole pumping test were carried out in the study area to analyze the spatial and temporal distribution characteristics of groundwater runoff direction,runoff type,runoff dynamics,runoff velocity,flow pattern and flow line of the underground river system.Contrast the difference of groundwater runoff characteristics in homogeneous karst water-bearing medium.The results show that the four sinkholes(drop points)in the study area all discharge from the underground river outlet No.S1 in the southwest,which proves that the direction of groundwater runoff in the area has the coexistence of rising and falling and the concentration of underground river pipelines;The types of groundwater runoff in the area are mainly karst cave-pipeline,centralized runoff,supplemented by small-scale,lateral branch pipeline recharge,and slow flow phenomenon exists in local faults;The dynamic instability of groundwater runoff and the seasonality of“quick recharge and quick discharge”are significant;The groundwater flow line in the area also has a U-shaped feature of irregular rise and fall,which leads to the drilling in the area to reveal that the buried depth of the groundwater level is greater than the static water level,and the vertical groundwater has pressure.Karst development in limestone area of underground river system is not uniform,which results in great difference and significant contrast between groundwater runoff characteristics and uniform karst water-bearing medium in runoff direction,runoff type,flow velocity,dynamic and flow line.The results can provide reference for groundwater development and protection in Guizhou karst mountain area.
作者
罗林
郑明英
王万金
LUO Lin;ZHENG Ming-ying;WANG Wan-jin(Geological Group,Guizhou Bureau of Geology and Mineral Resources Exploration and Development,Guiyang 550081,China)
出处
《地下水》
2024年第5期34-36,41,共4页
Ground water
基金
贵州省地勘基金项目(黔自然资函[2021]244号)
贵州省水文地质志修编(MCHC-ZG20212206-1)。
关键词
岩溶山区
地下水
非均匀
径流特征
karst mountain area
underground water
heterogeneous
runoff characteristics
