1900年以来祁连山地震带7级以上地震衰减特征  

Attenuation Characteristics of Earthquakes with M ≥ 7.0 in Qilian Mountain Seismic Zone Since 1900

作　　者：任雪梅[1] 李文君 

机构地区：[1]宁夏回族自治区地震局,宁夏 银川

出　　处：《地球科学前沿（汉斯）》2023年第8期979-986,共8页Advances in Geosciences

摘　　要：文章通过对1900年以来祁连山地震带7级以上强震发生后震中区范围内5级以上地震的发生情况进行分析,发现该区域7级以上强震发生后1~6年震中100~220 km范围内5级地震活动明显增强,表现为增震效应;7级以上强震发生的23~56年震中100~220 km范围内5级地震活动减弱,表现为减震效应。由于发震构造的不同,1920年海原的8 1/2级地震和1927年古浪8级地震的余震活动特征存在较大差异。In this paper, the occurrence of earthquakes with M ≥ 5.0 in the central area after strong earth-quakes with M ≥ 7.0 in the Qilian Mountain seismic zone since 1900 is analyzed. It is found that earthquakes with M ≥ 5.0 within 100~220 km of the epicenter are obviously enhanced 1~6 years after earthquakes with M ≥ 7.0 in this region, which shows the seismicity enhancement effect. The seismicity of earthquakes with M ≥ 5.0 after 23~56 years strong earthquakes with M ≥ 7.0 decreases within 100~220 km of the epicenter, which shows the damping effect. Due to the different seismogenic structures, the characteristics of aftershock activity of Haiyuan M8 1/2 earthquake in 1920 and Gulang M8 earthquake in 1927 are quite different.

关 键 词：祁连山地震带 衰减特征 增震 减震 发震构造 

分 类 号：P31[天文地球—固体地球物理学]