构造断裂发育地区的地下水流模拟  

SIMULATION OF GROUNDWATER FLOW IN THE FAULTS AREA

作　　者：王浩然[1] 朱国荣[1] 

机构地区：[1]南京大学地球科学系

出　　处：《南京大学学报（自然科学版）》1999年第3期323-329,共7页Journal of Nanjing University（Natural Science）

摘　　要：讨论了利用非均质、各向异性的地下水非稳定运动的理论［１］和相应的有限单元方法［２］，对一个构造断裂极为发育的富水地区的地下水运动采用非均质、各向异性的计算机模拟技巧，成功地处理了断裂带对地下水运动的影响，在此基础上建立了该区的地下水动态预测模型，为合理开发本区的地下水资源提供了准确的依据．A new numerical approach associated with finite element method for simulating unsteady groundwater flow in inhomogeneous and anisotropic formations is presented in the paper. The method can successfully simulate the groundwater flow in a water abundant faults area. The discussed area lies in the middle stream of Zi river in Zibo city, Shandong province. The aquifer system consists of Cambrian and Ordovician formation. The thickness of the aquifers is about 300～400m. The north of the area is covered by incompact capping of Quaternary and becomes a confined aquifer subsystem. Because of frequent tectonic movements in geological history, there are many fault belts affecting the groundwater flow in this area. Based on the difference of the properties of the major faults, the inhomogeneous area is divided into 20 subregions. Among the subregions, every major fault is situated at a distinct anisotropic subregion, which has different hydraulic conductivities in different directions. Thus, various impacts of the faults on groundwater movement are successfully simulated. With trial and error method and simplex optimization to fit, the hydrogeological parameters in the subregions of fault are excellently agreed with the actual hydrogeological parameters. Then a parameter comparison model is set up to compare the computed groundwater level with the observations. According to the model, with the actual data of rainfall, pumping and other discharge and recharge from September in 1989 to December in 1990, the computed groundwater flow field of the same period is well fitted to the real one. As a result of the appearance of the lowest (less than 400mm in 1989) rainfall and the highest (more than 1000mm) rainfall during the period, the biggest change of water level has been over 50m. The amount of data whose error less than 4.86% is 81.25 percent of the total quantity of the data. While the biggest error is only 5.31%. Furthermore, all of forecasted water curve of the observation hole is almost coincided with the measu

关 键 词：数值模拟 各向异性 构造断裂 地下水运动 

分 类 号：P641.2[天文地球—地质矿产勘探]