Tectonic creeping ground fractures are common in the ground fractures, and some regional ground fissures, which are concentrated at home and abroad, generally have the background of neotectonic activity. It is pointed out that under the action of steady and slow tectonic stress, if the strain accumulation reaches the critical value of rock formation fracture deformation, the ground fissure may occur on the surface, and with the increase of this stress, the ground crack will develop and expand gradually. In a large area controlled by the same stress field, where ground fissures are most likely to occur, it is the area where strain accumulates, the rock is fragile and the active structure changes violently, including the active fault zone, the active fold axis and the turning point of active structure rising and falling, and so on.
In the study of the ground fissures in Xi'an, it is generally considered that the Fenwei graben is a typical neotectonic active area in China. The concentrated occurrence of the ground fissure in this area is obviously synchronized with the intensification of the regional tectonic activity in time, and the distribution of the ground fissures is obvious. Many aspects, such as the mode of activity, obviously show uniform structural characteristics. Many scholars have put forward the generalizable model of tectonic mechanism of Xi'an ground fracture from different angles, among which the most representative one is Zhang Jiaming's theory of fault block tilting in 1990. It is believed that under the action of NNW extensional stress to the region, Activities of Xi'an extensional fault system with fault block tilting as its main active form constitutes the essence of the formation and development of the ground fissures in Xi'an.
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