Abstract: Based on the vertical component Z of geomagnetic field observed respectively at the stations of Sheshan and Chongming for 11 years from 2000 to 2010, we calculated the values of the geomagnetic Load-Unload Response Ratio (LURR) and analyzed the seismic activity in Shanghai and its adjacent areas in the same period of time. We discussed the usage of the value to predicting the earthquake and revised the original index system. The results show that: ① When the value of the LURR is greater than 3. 4, there is a important implication for predicting M_L≥4. 0 earthquake in Shanghai and its adjacent areas; ② The overall trend of the values of the LURR is consistent with the variation characteristics of the seismic activity in this area; ③ the result of the wavelet transform indicates there is the same period about 4. 5 year between the value of LURR and the seismic activity, and the phase variations are consistent in this period scale.

Key words: Geomagnetic LURR method, Seismic activity, Wavelet transform, Shanghai and its Adjacent Areas