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大同市是一个以地下水为主要供水水源的城市。地面沉降始于８０年代初，大约在此后的１０年中，随着地下水采量逐年增加，地面沉降不断加剧。１９８８～１９９３年通过建立控制面积４００ｋｍ２、网点８０个的Ｉ等形变水准网，监测到平均沉降速率为１７～２３ｍｍ／ａ，５年累计最大沉降量达１２４ｍｍ，地面沉降面积达１６０ｋｍ２。从其成因看，它包括了人工抽水土层压密、区域地壳构造下降和相邻区断层活动的牵引作用三者叠加的结果，其中抽水占主导地位。在地下水开采过程中，强烈地加剧了地裂缝活动，形成了与地面沉降相伴生的灾害性环境地质效应。自１９８３年以来全大同市产生了８条地裂缝，总长达２４余ｋｍ，并且较集中地分布在地面沉降中心区或边缘带以内，给城市建设和发展带来了巨大的经济损失和不良的社会影响。
Datong is a city where groundwater is the main water supply source. Ground subsidence began in the early 1980s, and about 10 years afterward, land subsidence intensified as the amount of groundwater collected increased year by year. From 1988 to 1993, the average deformation rate was 17 ~ 23mm / a. The maximum cumulative settlement in five years was 124mm and the ground subsidence area was 160km2 by establishing the I-level deformation leveling network with 400km2 controlled area and 80 outlets. From the cause of formation, it includes the results of superposition of the artificial pumping soil compaction, the descending of the regional crustal structure and the traction of fault activities in the adjacent area, of which the pumping is the dominant one. During the exploitation of groundwater, ground fissure activities are strongly aggravated, forming a disastrous environmental and geological effect that accompanies land subsidence. Since 1983, there have been 8 earth fissures in Datong, with a total length of more than 24 km and are mainly distributed within the center of land subsidence or marginal zone, which brings huge economic losses and poor economic benefits to urban construction and development social influence.