甘肃北山区域地下水流数值模拟研究  

Numerical simulation of regional groundwater flow in the Beishan area of Gansu

作　　者：曹潇元 侯德义[1] 胡立堂[2,3] CAO Xiaoyuan;HOU Deyi;HU Litang(School of Environment,Tsinghua University,Beijing 100084,China;Engineering Research Center of Groundwater Pollution Control and Remediation of Ministry of Education,Beijing Normal University,Beijing 100875,China;College of Water Sciences,Beijing Normal University,Beijing 100875,China)

机构地区：[1]清华大学环境学院,北京100084 [2]地下水污染控制与修复教育部工程研究中心,北京100875 [3]北京师范大学水科学研究院,北京100875

出　　处：《水文地质工程地质》2020年第2期9-16,共8页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目(41572220)。

摘　　要：掌握区域地下水流场是高放废物地质处置场选址及适宜性评价的重要先置条件。甘肃北山高放废物处置预选区面积广、数据资料少,准确划分该区域地下水流场和高放废物预选区选址的安全性评价都存在难度。本研究采用地表流域划分方法、多相流数值模拟软件TOUGH2-MP/EOS3和GRACE重力卫星等方法,建立了区域地下水饱和-非饱和流模型,并完成了模型识别和参数率定,论证了模型的合理性和可靠性。研究结果表明:约1%的降水量入渗至地面以下;地形条件是影响地下水流场的主要因素,而气候条件对地下水流场形态影响相对较小;区域地下水流动系统由北向南可分为三个子系统(Ⅰ、Ⅱ、Ⅲ),其中高放废物地质处置场预选区位于研究区南部独立的地下水子系统Ⅲ中,且该子系统面积最小。本研究为面积广、实测数据资料较少的干旱地区提供了一套有效的数值模拟方法,研究结果可为预选区选址的安全性评价提供重要依据。Understanding the regional groundwater flow field is the fundamental work for the site selection and suitability evaluation of high-level waste geological disposal sites.Due to the wide area and limited data,it is difficult to accurately divide the groundwater flow field in the area,and it also brings trouble to the safety evaluation of the site selection of the high-level waste pre-selection area.To solve this problem,a case study is carried out in the Beishan area of Gansu.The watershed division method,TOUGH2-MP/EOS3 software,which can describe the saturated-unsaturated groundwater flow,and the GRACE satellite data,are used to set up,run and calibrate the model respectively,and the reliability of the model is proved.The results reveal that(1)about 1%of the precipitation infiltrates into the groundwater;(2)topography of the study area is the main factor to determine the groundwater flow,and different precipitation has little impact on the regional groundwater flow field;(3)The regional groundwater flow system can be divided into three sub-systems(Ⅰ,Ⅱ,Ⅲ).The pre-selected area is located in the independent groundwater subsystem III with the minimum area in the south.This study can provide an effective simulation method for the arid area with a huge area and limited measured data,and also an important basis for the safety evaluation of the pre-selected area.

关 键 词：甘肃北山 高放废物地质处置 区域地下水流场 数值模拟 TOUGH2 GRACE 

分 类 号：P641.2[天文地球—地质矿产勘探]