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 o f P waves. Two earthquake examples that formed normal faults and three exam ples that formed strike slip faults are given. The smallest earthquake is t he 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 earthquak e on February 5,1996, and that of Harvard CMT to the same earthquake, the s imilarity between waveform of records and that of the synthetic in the samp le earthquakes, as well as the consistency between;the distribution of firs t motion signs of P waves and P, T regions, the solutions of focal mechanis m obtained are valuable, and the software developed is usable.