川滇地区走滑型地震烈度衰减特征研究

Intensity Attenuation Characteristics of Strike-slip Earthquakes in Sichuan and Yunnan Regions

为分析走滑型地震的烈度衰减特征,我们搜集并整理1900年以来川滇地区的145个5级以上震例和其中70个5级以上、破裂方式以走滑型为主的典型震例,利用联合椭圆衰减模型,建立该区域此类型地震烈度衰减关系。对比已有研究成果,结果表明,川滇地区破裂方式以走滑型为主的地震烈度衰减速度慢于西南地区,可能与该地区地震破裂方式、动力学过程等有关,但与川滇地区和中国西部的衰减规律相比没有明显差异。本文给出的烈度衰减关系在该区域此类地震的灾害快速评估和地震应急中具有一定参考价值,其他区域的适用性需进一步分析。

To analysis characteristics of intensity attenuation for strike-slip earthquakes, based on 145 magnitudeS5 earthquakes and 70 earthquakes of at least magnitude 5 with the mode of fracture to be mostly strike-slip earthquakes since 1900, this paper used the combined elliptic attenuation model and obtained intensity attenuation relationship for strike-slip earthquakes in Sichuan and Yunnan regions. Compared with existing study results, it shows that seismic intensity attenuation rate with strike-slip type earthquakes is slower than those of southwest China, this may be related to earthquake fracture mode, dynamic processes and so on. But compared with the seismic intensity attenuation law of Sichuan and Yunnan regions and western China, there were no significant differences. This intensity attenuation relationship given in this article about this type of earthquakes in Sichuan and Yunnan regions can provide an important reference in earthquake emergency or rapid disaster assessment.