The Wenchuan M_S8.0 Earthquake:Pre-seismic Activity and Maximum Aftershock Prediction

With the aim to find the features of the Wenchuan MS8.0 earthquake in development and activity process,we analyze the strong earthquake activity in western China since 2001,the seismicity in Sichuan,and the Wenchuan earthquake sequence.The Wenchuan earthquake occurred on the Longmenshan fault under the background that the strong earthquake activity was strong outside southwestern China but weak inside the area,the moderate-small earthquake increased in a big range and the medium-and short-term anomalies were active in a small range.The analogue analysis method,which is used to forecast the maximum strong aftershock of the Wenchuan earthquake,is accurate to the early judgment of the maximum strong aftershock.