台灣地震科學中心 2011 Antelope Workshop 2011-03-15 中央研究院地球科學研究所 Min-Hung Shih & Wen-Tzong Liang 3/15/2011 Ver. 0.21 Quick View Run dbdetect to execute STA/LTA detectors on the waveforms  Run dbpick on the database to modify picks  Run ttgrid to make a grid file  Run dbgrassoc to produce origin and event tables  Run dbloc2 on the database to modify picks and calculate earthquake locations  dbdetect  dbdetect runs STA/LTA algorithm on seismic data to determine the arrival times of seismic energy. step1 Copy parameter file on local directory >pfcp dbdetect your_directory step2 Edit dbdetect.pf >vi dbdetect.pf Execute dbdetect >dbdetect –arrivals – pf pf your_pf dbin dbout step3 STA/LTA algorithm the ‘short-time-average through longtime-average trigger' (STA/LTA) is the most broadly used algorithm in weakmotion seismology.  The algorithm processes filter seismic signals in two moving time windows – a short-time average window (STA) and a long-time average window (LTA).  Dbdetect.pf Dbpick -check arrivels ttgrid  Compute a travel time grid file step1 Copy parameter file on local directory >pfcp ttgrid your_directory step2 Edit ttgrid.pf >vi ttgrid.pf step3 Execute ttgrid >ttgrid –pf ttgrid.pf – time all db > db_grid step4 Display the grid >displayttgrid dbgrid local ttgrid.pf displayttgrid dbgrassoc  Dbgrassoc spatial grid search based associator/locator step1 Copy parameter file on local directory >pfcp dbgrassoc your_directory step2 Edit dbgrassoc.pf >vi dbgrassoc.pf Execute dbgrassoc >dbgrassoc –pf dbgrassoc.pf dbin dbout db_grid step3 dbgrassoc.pf Output of dbgrassoc origin - hypocenter parameters  event – the preferred origin for an event  arrival – phase, time of the seismic arrivals  assoc – connects arrival to origin, list travel time residuals, etc.  Dbloc2 - Interactive hypocenter location  >dbloc2 DBname Wonderful tutorials for Antelope Pavlis class assignments and tutorials for seismogram interpretation class using Antelope http://antelopeusersgroup.org/g515/index.html