Tectonic influence on karst development: a case study of Yiyuan basin, a typical karst area in Northern China

Tectonics, as one of the key factors affecting the development of karst, provides dynamics and spatial conditions for karst distribution and karst water. However, due to the influence of tectonics, there are obvious differences in karst formations between the north and south of China. As a representative of the northern karst type, this study analyzed the characteristics of Yiyuan Cave in the Yiyuan area and discusses the relationship between tectonics and karst development. Hydrogeological investigations were utilized to detect karst phenomena and spring points. Combined with rock samples, it discussed the development characteristics of karst in the north. The connection between spring flow and tectonics is analyzed. The results of the study show that: the Nanlushan karst cave group is vertically zoned by tectonic influence. There are differences in the ratio of CaO and MgO in the strata where karst is more developed, and the flow rate of karst springs is higher the closer to the tectonically developed areas. The Shangwujing fault is the structure that mainly controls the development of the stratigraphic lithology in the study area, and also influences the development process of karst. It leads to the differentiation of stratigraphic lithology in the carbonate zone, which plays a certain role in blocking karst water and controlling the flow of karst water. Under complex geological conditions, exploring the connection between karst development and tectonics is of great significance for the understanding of the northern karst system, which also provides a scientific basis for the development of karst springs and the protection of karst water.