Focal mechanism solutions of Wenchuan earthquake and its strong aftershocks obtained from initial P wave polarity analysis

We firstly read out initial P wave polarity from the digital wave form data given by Chinese national seismic networks, regional seismic network, temporary seismic network as well as some IRIS stations. Then employing grid point test method we obtain Focal Mechanism Solution of the great Wenchuan earthquake, which measured at 8. 0 M₂ occurred at 14 : 28 CST on May 12, 2008 in Sichuan province of China as well as those of some of its strong aftershocks (M≥ 5. 0). This group of focal mechanism solutions are very important complement of 9 optimized double-couple solutions published by Harvard university.