Fault is the product of geological structure, which marks the fracture and dislocation of strata. It is of great significance to geological research, geological resources exploration and groundwater flow field distribution. In addition, faults play an important role in geological modeling in the formation of geological bodies and the determination of work area boundaries. Therefore, it is an important work of geological modeling to depict faults realistically.

As a data type describing the spatial plane of groundwater system model, faults need to be clear in the modeling process: the spatial distribution of fault plane, the occurrence of faults at different points and the hydraulic properties of faults.

Fault data is mainly input in the form of graphics, and then used for modeling. There are two ways to express the fault on the plane. One is to draw the fault strike and mark the dip angle on a plane, such as a plane or geological map; The other is to draw fault lines on the section. Combining these two graphs, the spatial distribution of faults will be clear at a glance, and the occurrence of faults can be read by the system or given manually. The hydraulic properties of faults are necessary for the later groundwater simulation calculation, which can be stored in the database or directly in the fault properties of the model. The input method of geological structure modeling of groundwater system to faults is to combine MapGIS plane input with AutoCAD profile file input to establish profile space model.