Abstract：According to Aki’s singlescattering theory of coda, the coda Qc value,which is (89.2 ± 28.78) f 0.913 1 ± 0.154 3 in the Xiaolangdi reservoir area is estimated by use of the seismic waveform data recorded by short-period instruments from Xiaolangdi Reservoir Seismic Network. The results show that threre is a strong dependence between Qc value and frequency in the Xiaolangdi reservoir area and coda Qc value is small. Refering the domestic research results, combined with the numerical characteristics of coda Qc in this area, it is found that the tectonic activity is complex and the seismic activity level is high in the studied area,so the earthquake monitoring should be strengthened.
