΢�������ʱ��ʰȡ��΢�������ϴ�������е�һ����Ҫ���裬Ҳ�ǵز��ٶ�ģ�ͽ�������Ҫ���ݡ�Ϊ���ʰȡ���ȣ��������һ���µ��Զ�ʰȡ����ʱ��ķ����������������������ݵ�Сʱ��Э�����������ֵ��������Ϊ�����������뵽 STA/LTA �����ȷ����У��Ӷ�ʵ���Զ�ʰȡ����ʱ�䣬����� P ��ʱ������Դ��λ������ģ�ͼ�ũ��dz����ҳ��ˮ��ѹ�������΢�������ϴ������������÷���������Ч��ʰȡ΢�������ʱ�䲢ʵ����Դ��λ��

Picking up first break is an important step in micro- seismic data process��and it is the significant gist of velocity model establishment�� In order to enhance the precision of pickup��this paper presents a new auto- matic first break pickup method��by calculating the small time window covariance matrix characteristic value of the three- component seismic data��which can be introduced into the STA/LTA energy ratio method as the characteristic function to realize the first break pickup automatically�� After then��combined with the P wave time difference meth- od��the source location in the data process is achieved�� The results of the synthetic model and the micro- seismic data of shallow well hydraulic fracturing test of oil shale in Nong��an indicate that the proposed method can realize the automatic first break picking and source locating effectively��