马尼拉海沟俯冲带板缘地震特征及衰减关系研究  

Study on the Characteristics and Attenuation Relationship of Plate Margin Earthquakes in the Subduction Zone of Manila Trench

作　　者：郑旭 周少辉 ZHENG Xu;ZHOU Shaohui(Shandong Institute of Earthquake Engineering,Jinan 250021,China;Shandong Earthquake Agency,Jinan 250014,China)

机构地区：[1]山东省地震工程研究院,济南250021 [2]山东省地震局,济南250014

出　　处：《华南地震》2022年第1期86-96,共11页South China Journal of Seismology

基　　金：山东省地震局一般科研项目(YB2011)。

摘　　要：俯冲带通常位于陆地板块与海洋板块或者海洋板块之间的交界处,地质构造复杂,地震活动频繁。在南海海域,马尼拉海沟俯冲带对中国海洋战略及近海重大工程的实施位置至关重要。在缺少实际地震数据的前提下,为分析马尼拉海沟俯冲带地震动及其衰减关系特征,通过采用随机有限断层法模拟该俯冲带地震动,分析地震动加速度时程及反应谱特点,同时分别基于模拟数据和衍生方法,建立了马尼拉海沟俯冲带板缘地震动衰减关系。结果表明:峰值加速度(PGA)及短周期反应谱(Sa)的衰减关系模拟方法与衍生方法差异较小,都能适用,长周期反应谱的地震动衰减关系以衍生方法结果为准。由此建立的俯冲带板缘地震动衰减关系可以为南海海洋战略中近海工程建设提供重要依据。Subduction zone usually has complex geological structure and frequent seismic events which is located in the junction of the land plate and the ocean plate or ocean plates.Manila Trench subduction zone is crucial to the implementation of China's marine strategy and offshore engineering in the South China Sea.In the absence of actual seismic data,in order to analyze the characteristics of ground motion and its attenuation relationship in Manila trench subduction zone,stochastic finite fault model is used to simulate the ground motion in this subduction zone,and analyzes the characteristics of ground motion acceleration time history and response spectrum.At the same time,based on the simulation data and derivative method,the attenuation relationship of ground motion at the plate edge of Manila trench subduction zone is established.The results show that the difference between the simulation method of attenuation relationship and the derivative method for peak acceleration(PGA)and short-period response spectrum(Sa)is small,which can be applied,and derivative method is more accurate for long period than simulative ones.The attenuation relationship of slab-subduction ground motion in subduction zone established in this paper can provide an important basis for offshore engineering construction in the South China Sea.

关 键 词：马尼拉海沟 俯冲带 板缘地震 衰减关系 

分 类 号：P315[天文地球—地震学]