摘要
地震活动性图象反映了地震的群体特征。本文阐明了中国大陆,特别是中国东部地区的地震活动性图象具有空间分布的网格块体性;一定地区间地震发生的相关性;一定的地震活动图象在空间上常可有所平移再现等特征。这些图象的尺度均可达到成百上千公里。据此认为地震的动力也应有与此相当的大尺度。中国大陆地震基本集中在一个厚度仅为15 km的地层——发震能干层,与活动性图象的尺度相比,具有悬殊的宽厚比。因之认为地震构造应属一种薄壳结构。观测到的地震活动性图象与薄壳结构的失稳屈曲图形有同质同象的相似性。据此估算其量值与观测到的图象尺度颇为吻合。结论认为:地震活动性图象似受控于结构的失稳屈曲;地震构造可视为主要由发震能干层所构成的一种薄壳结构(薄皮构造)。
The seismicity pattern reflects the characteristics of earthquake clusters. This paper expounds that the seismicity patterns in China mainland, especially in the eastern regions of China are possessed of gridmassif nature in spatial distribution and of the correlatability of earthquake occurrence among certain regions, and that some seismicity patterns often have features such as parallel translation, reappearance in space, etc. The spatial scales of these patterns reach hundreds or thousands of Kilometers. Based on this, it is thought that the dynamic force of earthquakes should correspondingly have a large scale. Earthquakes in China mainland basicallyconcentrate in a stratum only 15 km thick in the crust--the seismogenic capable layer. Interms of width/thickness ratio, it is of great disparity in comparison with the scale of seismicity pattern. Therefore, it is considered that the seismotectonics should belong to a thin shell texture. The seismicity patterns observed have a similarity to the unbalanced yielding graph of a thin shell nature and appearance. Accordingly, the value estimated is rather consistent with the scale of the seismicity pattern observed. The conclusion is that the seismicity pattern seems to be under the control of the unbalanced yielding of the texture; the seismotectonics can be regarded as a thin shell texture mainly formed by the seismogenic capable layer.
出处
《地震》
CSCD
北大核心
1989年第1期1-9,共9页
Earthquake
