鄂尔多斯盆地地下水资源与开发利用

鄂尔多斯盆地是我国西北地区的大型构造沉积盆地,以前寒武系变质岩为基底,依次沉积了下古生界碳酸盐岩、上古生界—中生界碎屑岩和各种成因的新生界,总厚度达6000m。根据盆地的地质构造特征和水文地质条件,将鄂尔多斯盆地含水岩系划为周边寒武系—奥陶系碳酸盐岩岩溶含水层系统、白垩系碎屑岩裂隙孔隙含水层系统和盆地东部基岩裂隙水与上覆第四系松散层孔隙含水层系统。在含水层系统划分的基础上,以含水体之间是否具有统一的水力联系和稳定的水动力场和水化学场为依据,将周边岩溶水可进一步划分为10个水流系统和22个子系统,白垩系地下水划分为5个水流系统和11个子系统,石炭系—侏罗系裂隙水与上覆松散层孔隙水划分为9个地下水系统。系统论述了含水层系统特征,区域水文地球化学特征和地下水循环规律,对鄂尔多斯盆地地下水资源进行了全面评价,针对能源基地建设的供水急需,提出了地下水合理开发利用建议。

Groundwater Resources of the Ordos Basin and Its Development and Utilization

The Ordos Basin is a large-scale sedimentary basin in Northwest China.From bottom up,the hydrostratigraphic units in the basin are pre-Cambrian metamorphic rocks,lower-Paleozoic carbonate rocks,upper-Paleozoic to Mesozoic clastic rocks and Cenozoic deposits.The total thickness is up to 6000m.Three groundwater systems are present in basin,based on the geological and hydrogeolgical settings,such as the karst groundwater system,the Cretaceous clasolite groundwater system and the Carbonate-Jurassic and Quaternary groundwater system.On the basis of the three groundwater systems, according to hydraulic connection and presence of uniform hyduaulic and hydrogeochemical fileds,the karst grounewater system is further divided into 10 flow systems and 22 sub-systems,the Cretaceous clasolite groundwater system can be 5 flow systems and 11 sub-systems,and the Carbonate-Jurassic and Quaternary groundwater system is 9 flow systems.The paper systematically discusses regional patterns of the aquifers,hydrogeoehemistry and groundwater flow,presents a full assessment of groundwater resources,and puts forward suggestions on rational development of groundwater in the basin.