新版地震区划图地震活动性模型与参数确定

The Earthquake Activity Model and Seismicity Parameters in the New Seismic Hazard Map of China

地震活动性模型和地震动预测模型是概率地震危险性分析的两个核心。在新版地震区划图中,依据板内地震活动空间不均匀性分布的特点,在概率地震危险性分析方法(CPSHA)中采用了由地震统计区、背景潜在震源区和构造潜在震源区构成的三级层次性潜在震源区模型,并构建了相应的地震活动性模型。本文在论述CPSHA方法及其地震活动性模型基本概念的基础上,重点介绍了新版地震区划图地震活动性模型的三级潜在震源区模型的构成、地震活动性假定和基本特点,同时,也对新版地震区划图地震活动性模型的重要参数确定思路、方法与结果进行了介绍。本文将为更好地认识与理解我国新版地震动参数区划图提供有益的参考。

The model of earthquake activity and the model of earthquake ground motion are two primary elements ofprobabilistic seismic hazard analysis. The CPSHA, a modified PSHA method, is used for the new seismic hazard map of China, which has advantages of characterizing the non-uniform spatial distribution of intraplate earthquakes in China. The earthquake activity model of CPSHA is established based on a tri-classes seismic source model, which consists of the seismic province, the of background seismicity zone, and the tectonic features zone. In this paper, the primary principles of the earthquake activity model of CPSHA are introduced firstly, and then the tri-classes seismic source and the characteristics of its earthquake recurrence model are presented in detail. Also in this paper, the general framework of determining physical seismicity parameters of the earthquake activity model used by the new seismic hazard map is described briefly and the final products are demonstrated here. This paper will be helpful for better understanding the results of the new seismic hazard map of China.