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对中国大陆地震的震源深度资料作了系统研究.震源深度的研究,对于探索地震孕育和发生的深部环境,地震能量集结、释放的活动构造背景,以及地壳内部构造变形及其力学属性等都有非常重要的意义.以1970年1月～2000年5月期间中国大陆ML≥2.0级并给出深度的31282次1和2类精度的浅源地震为基础,研究了深度分布特征,并采用网格滑动平均方法,统计了网格内地震的平均深度.结果表明,中国大陆平均深度为（16±7）km,东部地区为（13±6）km,西部为（18±8）km,东部比西部平均偏浅5km.我国大陆地震深度最大的地区是新疆西南部地区,即塔里木地块的西端和西南缘.震源深度与构造分区的关系密切,青藏活动地块震源深度平均为（33±12）km.新疆活动地块为（21±10）km,华北为（14±7）km;东北为（11±5）km;华南为（10±4）km.完整地块边界上的地震较深,其中最明显的是塔里木盆地的西南缘、北缘;准噶尔盆地的南边缘,阿拉善地块的南边缘;鄂尔多斯地块的东、西两侧以及四川盆地的西边缘.在新生性的破裂带上地震偏浅,如滇西南地震带及张渤地震带.另外,还根据我国震源深度分布特征,讨论了壳幔（主要是地壳）力学行为、变形属性和破坏方式.
A systematic study of focal depth data of earthquakes in mainland China has been conducted in this paper.Research on depth of focal depth is of great significance for exploring the deep environment of earthquake occurrence and occurrence, seismic energy accumulation, tectonic setting of release and the tectonic deformation and mechanical properties of the crust It is of great importance to study the depth distribution based on the shallow earthquakes of ML degree 2.0 with a depth of 31282 times 1 and 2 in China from January 1970 to May 2000. The depth distribution characteristics The average depth of earthquakes in the grid is calculated.The results show that the average depth of the Chinese mainland is (16 ± 7) km, the eastern region is (13 ± 6) km, the western is (18 ± 8) km, the eastern Which is 5km less than the average level in the western part of China. The largest depth of earthquake in China is located in the southwest of Xinjiang, that is, the western end and the southwestern margin of the Tarim block. The focal depth is closely related to the tectonic zoning. The depth of focal depth of the Qinghai-Tibet block is (33 ± (21 ± 10) km in Xinjiang, (14 ± 7) km in North China, (11 ± 5) km in Northeast China and (10 ± 4) km in South China. Seismicity on the complete block boundary Deep, the most obvious of which is the Tarim Basin On the south margin of the Junggar Basin and the southern margin of the Alashan Block, on the east and west sides of the Ordos Block and on the western margin of the Sichuan Basin, and the shallow earthquakes on the neogenic rupture zone, such as Yunnan Southwest seismic zone and Zhangbian seismic zone.In addition, the mechanical behavior, deformation properties and failure modes of crust and mantle (mainly the crust) are also discussed according to the depth distribution of the hypocenter in China.