地下含水层水资源赋存条件及其水化学特征—以贵州省安龙县幅为例

以贵州省安龙县1∶50 000水文地质图幅为例，采用含水层探采井的水质、水量监测数据，分析不同含水层水资源赋存特征及其与水化学的相关性。研究结果表明:（1）研究区含水层可分为纯碳酸盐岩管道含水层、非纯碳酸盐岩裂隙含水层、碎屑岩裂隙含水层、松散岩类孔隙含水层4种类型，各含水层中地下水水化学类型均以HCO-Ca?Mg型为主；（2）除非纯碳酸盐岩含水层探采井的降深与水体中Mg2+、HCO-3浓度呈现出显著的负相关性（R2=-0.77/-0.74）外，其余离子浓度与钻井单位涌水量、降深的相关性均不显著，相关系数(R2)均小于0.3；（3）非纯碳酸盐岩含水层和松散岩类含水层的总矿化度（TDS）、总硬度（TH）含量均比纯碳酸盐岩含水层低5 mg?L-1以上，TDS、TH的高值区均集中于纯碳酸盐岩含水层中，而低值区则分布于松散岩类含水层。 

Groundwater occurrence condition and hydrochemical characteristics:A case study of Anlong county map sheet in Guizhou Province

The development of fissures and karst caves in soluble rock strata in karst mountainous areas leads to a complex condition for groundwater occurrence, and affects the ability of water to dissolve solid substances. To have a better understanding of the relationship between groundwater occurrence and hyrochemical field in karst area, a case study was conducted in Anlong county of Guizhou Province, based on the data derived from the 1/50，000 hydrogeological mapping of Anlong country map sheet. The area is located in the transition zone between the Yangtze land mass and Youjiang orogenic belt, with a fairly complex condition in geological structure, strata and lithology. The strata of the whole area are mainly those the middle to lower Triassic, with occasional exposures of the Quaternary clay, sub-clay and the Permian clastic sedimentary rocks, which belong to typical special karst hydrogeological and geomorphic areas. Through exploration well water test and groundwater hole pumping test, we obtained the data of aquifer flow rate, drawdown, water chemical index values, then established the relationship between groundwater occurrence and the the hydrochemical characteristics, in order to explore the influence of the resource occurrence conditions on hydrochemical characteristics of the aquifer studied. Results show that the aquifers in the study area can be divided into four types, i.e. pure carbonate rock, chert-rich fractured carbonate rock, fractured clastic rock and loose primary aquifers. Hydrochemical type of the aquifers is dominated by HCO-Ca?Mg type. Except for the negative correlation between the depth of the exploration and production wells in the chert-rich carbonate rock aquifer and the concentration of Mg2+and HCO-3 ions in water (R2=-0.77/-0.74), the correlations between other ion concentrations and hydrogeological parameters (unit water inflow, drawdown) are not significant, and the coefficient R2 is less than 0.3. The total dissolved solids (TDS) and total hardness (TH) contents of the chert-rich carbonate rock aquifers and primary aquifers are lower than that of the pure carbonate rock aquifer by more than 5 mg?L-1, respectively. Furthermore, the total salinity and total hardness both with high values are concentrated in areas of the pure carbonate rock aquifers, while the low value areas are distributed in primary aquifers.