Distribution Pattern and Causes of Ground Fissures in the Ziyang Mountain Area
In order to understand the genesis mechanism of ground fissures in the Ziyang Mountain area of Jining City,the current situation and distribution patterns of ground fissures in the area were studied through methods including data collection,geological measurement,drilling,geophysical exploration,remote sensing interpretation,mountain engineering,indoor experiments,water level dynamic monitoring,engineering measurement,and comprehensive analysis.The results show that there are 6 exposed areas of ground fissures in the region.There are three types of cracks:linear,intersecting,and irregular collapse.All ground fissures are developed in forest planting areas,and before the area was changed from an agricultural area to a large-scale forest planting area,there were no reports of ground fissures reported by villagers.It can be inferred that the appearance of ground fissures is strongly related to the planting of trees.After investigation,there is a correlation between tree transplantation and the occurrence of ground fissures;The direction of ground fissures appearing on the surface is consistent with the direction of tree planting.It is speculated that the vertical cutting depth of the ground fissure may reach the bottom of the expansive soil layer.It is concluded that primary condition for controlling ground fissure activity in the research area is the distribution of expansive soil,followed by the degree of tree transplantation,tree planting,and hydrodynamic activity migration conditions.