To estimate focal mechanisms of moderate earthquakes using a long period surface waveform fitting method as well as first motion signs of P waves

A procedure that is used to estimate focal mechanisms of moderate and small earthquakes using surface waveform fitting method and first motion signs of P waves. Two earthquake examples that formed normal faults and three examples that formed strike-slip faults are given. The smallest earthquake is the one with M(L)4.5 occurred on December 16, 1996, at Beijing Shunyi. Based on the similarity between the solution of Yunnan Lijiang M(S)6.0 earthquake on February 5, 1996, and that of Harvard CMT to the same earthquake, the similarity between waveform of records and that of the synthetic in the sample earthquakes, as well as the consistency between the distribution of first motion signs of P waves and P. T regions, the solutions of focal mechanism obtained are valuable, and the software developed is usable.