川北山丘区地下水补给特征与定量研究

Quantitative Research on Groundwater Recharge in Mountain Area of North Sichuan

针对川北山丘区地下水资源和污染防护研究中地下水补给难以定量等问题,以川北典型山丘区平溪河北岸的山丘区子流域为研究对象,布设监测孔并对其地下水的水位和水温开展动态监测,并基于大气压监测数据校正地下水监测水位,分析了山丘区地下水水位及水温的年内动态变化特征;采用渗水试验和分段双栓塞水文地质试验获取含水层空间渗透系数;基于达西断面法定量计算了研究区内观测断面的地下水径流补给量,并建立了月降雨量与降水入渗系数的函数关系,结果显示:研究区多年平均大气降水入渗补给量为16.61mm,多年平均降水入渗系数为0.0182;月降雨量与降水入渗系数呈幂函数关系;此成果可为研究区地下水资源、地下水防污性能评价及地下水数值模拟等研究提供重要依据。

It’s difficult to quantify groundwater recharge for the groundwater resources and pollution prevention study in the mountain area in North Sichuan Province. This paper studied on the representative mountain hydrographic sub-basin in the north bank of Pingxihe river, based on the route monitoring borehole, and carried out dynamic monitoring of groundwater level and temperature, the water table of the groundwater monitoring data were corrected by atmospheric pressure monitoring data, the variation characteristics of groundwater level and temperature during the year were analysed, and the space permeability coefficients of aquifer were obtained by seepage test and hydraulic test with double packer. Based on the law of Darcy Setion, the quantitative groundwater recharge of the section was calculated; the function of momthly rainfall and precipitation infiltration coefficient were established. The results show that the annual average precipitation recharge of the study area is 16.61mm/a, and the average precipitation infiltration coefficient is 0.0182; with a power function of the monthly rainfall and precipitation infiltration coefficient.