Abstract: By retrospectively collating seismic belt anomalies in Ningxia since 1970, we analyzed the temporal and spatial characteristics of seismic belt anomalies, as well as, the anomaly threshold of internal and external seismic frequency ratio, obtained the parametric fitting equations of major earthquake and seismic belt, summarized and the prediction indexes of seismic belt in Ningxia, which provides some support and basis for the short-term earthquake tracking, discussion and evaluation technical schemes in Ningxia. The results showed that ① There were 12 significant seismic belts with M_L≥2.5 in Ningxia and its adjacent areas since 1970, among which, 8 earthquakes with M≥5 occurred at the end of the strip within one year after the end of the belts, and the dominant seismic reflection period was half a year, which could pass the R-value scoring test of prediction efficiency, and had certain medium-term prediction significance. ② There was a good linear positive correlation between the onset time, magnitude of the main earthquake, and the length, duration, total energy of the belt. The reference mean value could be given by the regression equation. The end of the belt was a favorable place for the occurrence of moderate strong earthquakes in the future. ③ In Ningxia, the average frequency ratio of the inner and outer belt was generally low. During the formation of the seismic reflection belts, there was a significant high value more than 0.75 but less than 2 times the mean square error, and the abnormal high value of the falsely reported belts was not significant.

Key words: Seismic belts, Frequency ratio of seismic belts, Prediction indexes