中国及其邻区地震深度的特征

系统地研究了中国及其邻区地震深度的一些时空变化特征后发现：５１％的地震发生在０－１９ｋｍ间，１０、１５、２０ｋｍ为几个地震多发层位；大陆地震的深度小于周邻地区地震的深度；大陆西部地震的深度大于东部地震的深度，这与大陆地壳西厚东薄的结果相吻合；中俄朝交界区及日本海、兴都库什－帕米尔、琉球群岛、缅印交界区和台湾地区地震的深度大，这与有关板块间的相互碰撞、挤压或俯冲等运动有关；兴都库什－帕米尔地区的地震

THE CHARACTERISTICS OF EARTHQUAKE DEPTH IN CHINA AND ITS ADJACENT AREA

Some spacio-temporal characteristics of earthquake depth in China and its adjacent area have been studied. 51 percent of the earthquakes occurred within 0-19 km below the earth surface. 20 km, 10 km and so on are some layers where earthquakes occurred frequently. The depth of earthquakes in the mainland of China are shallower than that round the mainland. The earthquakes in west mainland are deeper than that in the east, it is identical with that the crust in west mainland is deeper than that in the east. The eatthquakes in the border of China and Russia and Korea, Japanese Sea, Pamirs area, the Ryukyu Island, the border of india and Burma, and Taiwan are deeper than that in other area. It may be due to the collision, press and subduction of some plates. There are more and deeper earthquakes in Pamirs than in the border of india and Burma. The earthquake in the border of Tibet and Nepal are few and shallow, which indicated the active style that the india plate presses the Europe-Asia plate. The depths of early aftershocks varied in a large range, but the depths of late aftershocks tend to be a stable one. The deeper the earthquake is, the greater the magnitude is. The earthquake depth can be a principle for earthquake zoning.