Abstract:

In order to study the evolution of karst spring system and predict the spring flow, we simulated the evolution of karst dissolution in homogeneous and heterogeneous aquifer system by coupling seepage model and karst dynamic model. It’s found that the water level of the homogeneous aquifer system changes slightly at initial stage and decreases significantly at initial stage at the middle-late stage, while the initial water level of the heterogeneity aquifer system decreased significantly and remains stable at the middle-late stage. In terms of the fracture aperture, the maximum value of the aperture during the same period in the heterogeneous model is 4-5cm larger than that in the homogeneous model. Spring flow of the two systems is small at the initial stage and increases rapidly at the middle-late stage, but the time of increasing and spring flow at each time point are different. The flow of heterogeneous system increases earlier and the flow is larger. The exponential function and polynomial function are employed to fit the curves of the spring flow process in the homogeneous and heterogeneous system. The research provides a new way for simulation of evolution of the karst groundwater system, and also provides scientific basis for groundwater resources evaluation in the karst area at the same time.

Key words: evolution of the spring system, spring flow, homogeneity, heterogeneity