摘要
本文对宁波盆地四种地下水的矿化特征、成分起源、经历过的主要地球化学过程做了综合研究。认为:山边淡水来源于现代降雨和河水补给,是最有开发游力的可再生水资源;微咸水起因子海侵时海水混合,透镜状淡水是海侵时封闭在含水层中的古淡水,后两者都没有现代补给,急需加强管理和保护;盆底基岩水的化学成分来源于水对岩石矿物溶滤,受开采影响、基岩水已对上覆透镜状淡水体发生了越流补给。
Four principal groundwater types have been distinguished on the basis of the hydrochemical properties, and then the origin of each groundwater type is discussed.Freshwater in the piedmont alluvial fan is characterized by a very low total dissolved solids content (generally TDS<100 mg/1). This type of groundwater is recharged by moderm precipitation; it is the most important renewable water resource in the area.Brackish watei in aquifers Ⅰ and Ⅱ in the plain is characterized by a high total dissolved solids content(generally TDS=2 000—8000mg/1)and a very low sulfate concentration. It mostly belongs to sodium chloride type. The water is primarily formed by mixing of seawater and freshwater, accompanied by cation ion exchange and sulfate reduction. The lenticular freshwater body in aquifer Ⅱ should be'old water' that was closed in the aquifer during previous transgression. It is necessary to contrail the consumptive use of the brackish and lenticular freshwater, because they are nonrenewable resources.Groundwater in the bedrock aquifer evolves from the sodium and calcium bicarbonate type with a low total dissolved, solids content (<1000 mg/1) to the calcium and sodium sulfate type with a high total dissolved solids content (1000—8000 mg/1)and then to the sodium chloride type with a still higher total dissolved solids content (9000—33000 mg/1), Its chemical composition is primarily controlled by the dissolution of minerals in the aquifer.
出处
《地质论评》
CAS
CSCD
北大核心
1990年第5期414-422,共9页
Geological Review
