Evolution process of synthetic anomalous intersection zone of C,D and M_f values before moderately strong earthquakes in South China area

According to the activities of moderate and small earthquakes which usually have a strengthening process before a large earthquake and the phenomena that large earthquakes often occur in the periphery of the anomalous zone,the authors proposed that the intersection zone of the parameters describing the characteristics of the temporal,spatial and intensity distribution of earthquakes(the spatial concentration degree C,the seismic risk degree D and the seismic intensity factor M f)could be used to predict future moderately strong earthquakes.The application of the method to the earthquake prediction in South China area has shown that the accuracy of estimated epicentral location might reach 2 in radius.Finally,the middle and sort term characteristics of the synthetic anomalies are also summarized.