香港地区地震风险评价和设防区划  

THE SEISMIC RISK ASSESSMENT AND SEISMIC ZONING OF HONG KONH REGION

作　　者：李焯芬[1] 蒋溥[2] 梁小华[2] 

机构地区：[1]香港大学土木及结构工程系香港 [2]国家地震局地质研究所

出　　处：《工程地质学报》1998年第1期40-54,共15页Journal of Engineering Geology

摘　　要：香港地区隶属于中国板内地震区中的东南沿海块缘地震带。港－九块体为晚中生代至早第三纪以来以持续稳定上升为主的块体，块体活动性明显地低于其周边相对下沉的中新生代盆地。为此，赋予港－九块体为最大可信震级Ｍ＝５．５级潜在震源区，而其周边中新生代断陷盆地则为最大可信震级Ｍ≥６．０潜在震源。从大陆地震构造成因的环境、潜在震源可信震级范围Ｍ＝５．０～７．５和近源地震动饱和等三个方面的可比性，结合中国大陆地震震源破裂尺度和地震烈度影响场，所建立的反映中国地震构造和震源破裂及地震烈度影响场特点的ＰＧＡ和反应谱地震动衰减预测关系式可用于香港地区。以５０％概率时的中值对中国强震记录的对比，本研究所提供的经验期望预测关系式，能包络实际的资料。因此，用此地震动衰减预测模式对香港地区地震危险性进行评估，将会得到相对保守地震动预测值。通过香港地区基岩地震动危险性分析和计算，参照中国大陆地震设防标准，进行了基岩设计参数确定和区划。以年概率Ｐ＝０．０２、Ｐ＝０．００２、Ｐ＝０．０００４三个概率标准，对应的地震动重复周期大约分别约为５０ａ，５００ａ，２５００ａ的基岩ＰＧＡ和反应谱，作为香港地区基岩上构筑物和建筑物可选的基本设防的参数。香港的三?The Hong Kong Kowloon Block which have been uplifted continually and stable since late Cretaceous Paleogene period is identified and determined as a potential source with maximum credible magnitude M=5.5, while the late Cretaceous Paleogene fault basins which are located around the Hong Kong Kowloon Block are determinated as potential source with maximum credible magnitude more or equal 6.0 based on the characteristics of seismo geology tectonic activities in the Hong Kong and its adjacent regions. The attenuation law of peak ground acceleration (PGA) and standard response spectra of acceleration (β) with damping 5% underlain by rock ground were determined by comparing Chinese continent with Westen of USA in the similarity of tectonic environment of continental earthquaks, potential source with credible seismic magnitude 5.0～7.5, and considering ground motion saturation at near source. The near source attenuation model of acceleration and response spectrum also reflect the field of Intensity distribution in East China and the dimension of source faulting in Chinese continent. The seismic hazard analysis and calculating of bedrock ground motion were completed by considering the ground motion attenuation model with near source saturation and using ordinary method of seismic hazard analysis based on Poisson probability model for the Hong Kong region. In this paper the seismic design parameters underlain by rock ground and its zoning which contain peak ground acceleration and acceleration response spectra with annual exceedance probability level p= 0.02, 0.002 and 0.0004 are also was given . The seismic parameters and the corresponding zoning maps could be satisfied for the two level seismic design of many engineering structures.

关 键 词：地震 风险评价 高防区划 香港 地震烈度 

分 类 号：P315.9[天文地球—地震学] P315.5[天文地球—固体地球物理学]