The earth-resistivity anomaly characteristics analysis before the moderate earthquake in North China;

Study on ground motion attenuation relationship of moderate earthquake risk areas

The spatial\|temporal features of moderate earthquakes in the Gansu region are studied.

The moderate-short term anomalies before the moderate-strong earthquakes were finded by a long-term and reliable data of the ground tilt at Chaoyang seismic station in Liaoning province,it was an impotant basis for the earthquake prediction.

The results show that the mercury anomalies respond well to the moderate-strong earthquake in the middle areas of the Gansu Province (middle-east areas of Qilian Mountain belts) and show as the mid-term and short-term anomalies.

This article deals with a study conducted about the relevance of seismic activities far and near before a mid-strong earthquake in Daxinganling earthquake belt and assists to determine the medium and long-term earthquake prediction.

Relationship between small earthquake activities and medium-strong earthquake around Ganzi area;

Based on the analysis above, the characters of medium and short term anomaly variation in ground resistivity, corresponding to medium-strong earthquakes, appeared in the Linfen Central Seismological Observatory, Shanxi , a.

The results show that medium-strong earthquakes occurred many times in Yunnan in three months;medium-term synchronous anomalies of seismic parameters including Vp/Vs ratio,modulating ratio of small earthquakes and focal depth as well as near-field anomalies such as activation of local medium-small earthquakes,acceleration-quiet process and precursor earthquake swarm appeared before the ea.

Most moderate earthquakes that occurred in Ningxia and its vicinity are isolated type ones,so it is difficult to give a good mid-,short-term and impendingearthquake prediction.