Research on the completeness of earthquake data in the Chinese mainland (I) — North China

In terms of the temporal-spatial distribution features of earthquakes, we study the completeness of historical data in North China where there is the most plenty historical data and with the longest record history by some methods of analysis and comparison. The results are obtained for events withM _s≥4 3/4 are largely complete since 1484 in North China (except Huanghai sea region and remote districts, such as Nei Mongol Autonomous region), but quakes withM _s≥6 are largely complete since 1291 in the middle and lower reaches of the Yellow River. Contribution No. 94A0049, Institute of Geophysics, SSB, China. This subject is one of the important projects of the State Seismological Bureau (No. 85-05-01-01-01).