【摘要】 断层的存在影响着地下流场的运移和分布。该文建立了一个理想地区的地下含水系统模型,应用Modflow软件,考虑断层倾向、走向、渗透系数等因素的影响,采用数值模拟方法研究并探讨了断层对模拟区渗流场水头分布的影响特征。研究结果表明:①倾向不同的断层,以垂直断层对流场水头值的影响最为显著;②不同走向断层对流场的影响,主要受断层走向与流线夹角的控制,夹角越大,对流场的影响越显著;③断层的导水性质对模拟区流场水头值分布的影响较大,断层表现为导水或阻水性质,主要取决于断层渗透率与周围介质渗透率的关系;④断层附近的流场梯度变化较大,距离断层越近,流场受断层的影响就越明显,随着离断层距离的增大,影响效应逐步减弱。这项研究结果有助于深入认识断层对地下流体动态的影响,以及对地震前兆特征的解释。更多还原

【Abstract】 The transportation and distribution of groundwater are affected by the existence of faults. In this article, by applying Visual Modflow, and modeling environment for practical applications in three-dimensional groundwater flow, we build the mathematical model of a conceptual region’s groundwater system and research the groundwater seepage under the influence of faults with different dips, strikes and permeability. According to the results made by the identification and analysis with the model, we draw the conclusions as follows: ① Faults with different dips have a different role on the flow field, among the faults with same strikes and other characteristics, vertical fault is the most significant one. ② The impacts of faults on the entire region flow field of faults depend on the angles between the strike and the flow lines of the entire region flow field. The bigger the angle is, the more significant the impact is. ③ Different permeability is also an important factor that affects the distribution of the region flow field. Whatever the fault is considered as a conduit or a barrier, it depends on the differences of the conductivities between fault and protolith. ④ The distance from the fault is also one of the factors that affects the trends of water wells. The closer the distance is, the more obvious the change of water level is. As the distance becomes farther, the impact is not significant. This study will help us to further understand the dynamic effect interaction between fault activity and the migration of underground fluid, and also help us to deepen understanding of the mechanism of precursors during the process of earthquake generation.更多还原