喜马拉雅地震带地震活动性参数确定

GB 18306—2015《中国地震动参数区划图》发布距今已有十多年，期间，地震资料（尤其是青藏地震区地震资料）发生了较大变化，及时开展相关地震带地震活动性参数研究对重大建设工程抗震设防安全具有重要意义。本文研究补充了600余条地震目录，其中8.0～8.9级地震7次，7.0～7.9级地震35次，并分析了地震资料的完整性：由于历史、地理、人文的原因，喜马拉雅地震带地震遗漏较严重，7级地震直至1897年才基本完整，6级地震直至1950年才基本完整，5级地震直至1980年才基本完整；本文根据8级以上地震密集活动时段划分了地震活动周期，公元1803年以来可以划分出2个活动周期，并对未来地震活动进行了预测；采用多种方案拟合了喜马拉雅地震带的b值和4级以上地震年发生率：b=0.90，v4=162，并与前人的计算结果进行了简单对比。

Determination of Seismicity Parameters in Himalayan Seismic Belt

It has been more than ten years since the release of GB 18306—2015 "Seismic ground motion parameters zonation map of China". During this period, great changes have taken place in the seismic data, especially in the Qinghai Tibet seismic area. Timely research on the seismicity parameters of relevant seismic zones is of great significance for the seismic fortification safety of major construction projects. This work has supplemented more than 600 earthquake catalogs, including 7 earthquakes of M8～8.9 and 35 earthquakes of M7～7.9, and the integrity of seismic data is analyzed. Due to historical, geographical and cultural reasons, the earthquake omission in the Himalayan seismic belt is serious. The M7 earthquakes were basically complete until 1897, the M6 earthquakes were basically complete until 1950, and the M5 earthquakes were basically complete until 1980. The seismicity period is divided according to the intensive activity period of earthquakes above M8. Since 1803, two activity periods can be divided, and the future seismicity is predicted. Multiple schemes are used to fit the b value of the Himalayan seismic belt and the annual occurrence rate of earthquakes with M≥ 4: b = 0.90, v4 = 162, and the results are simply compared with the previous calculation results.