The Study On Development Characteristic And Formation Mechanism Of Ground Fissures In Linfen Basin

Linfen basin is located in the south of Shanxi graben system. It is surrounded by LvliangMountain in the west,and Zhongtiao Mountain as well as Huo Mountain in the east. North andsouth of the basin are Lingshi hilly area and Zijin Mountain respectively. Linfen Basin andYuncheng Basin are separated by the uplift of Emei mesa. Within the basin, buried faults develop,neotectonism active, and many devastating earthquakes generated in history, which make LinfenBasin a growing basin. There have been78ground fissures so far inside the Basin since they firstoccurred in1970s. Now they are becoming one of the major geological disasters in Linfen Basin,causing significant threat to urban and rural construction as well as people’s lives and property.Therefore, carried out formation mechanism research on ground fissures inside Linfen Basin canprovide reference not only for mechanism of ground fissures within growing basin, but also fordisaster prevention and mitigation in Fenwei Basin.Through detailed investigation, distribution and developmental status of ground fissures withinthe basin are ascertained, and plane distribution features of ground fissures are summarized in thispaper. Focusing on typical ground fissures, trenching and drilling are used to reveal their sectionalstructure features, and geophysical exploration is used to identify the relationship between groundfissures and active tectonic underlain. Based on these, mechanism of ground fissure mass withinLinfen Basin is analyzed and reaches the following main conclusions:(1) According to the characteristics of tectonic activity, Linfen basin can be divided into twosub-faulted basin and six new tectonic units, that are Linfen depressed basin and Houma depressbasin, Xinzhi convex, Hongdong concave, Linfen concave, Fushan convex, Xiangfen convex andHouma concave respectively. Linfen Basin is titling basin with the characteristic of “west thick eastthin”.(2) Through data collection, field survey and site investigation, development characteristics ofground fissures within Linfen Basin are revealed.(3) The activity features of ground fissures inside basin are: surface activity gives priority tolevel tension while deep activity gives priority to vertical dislocation, ground fissures’ movementare interrupted, different and will continue to expand. (4) Formation mechanisms of ground fissures within Linfen Basin are summed as: basintectonic inoculates fissures, faulting tectonic controls fissures, seismic activity leads to fissures,pumping...