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Min-Hung Shih 1/22/2015 Ver. 0.4

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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

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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 step3 Execute dbdetect >dbdetect -arrivals -pf pffile dbin dbout

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STA/LTA algorithm STA/LTA STA Short Time Average LTA Long Time Average STA LTA (threshold)

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STA window LTA window

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dbdetect.pf Globel parameters Design multi-filters Assign station & channel reject station & channel Design multi-filter for individual station & channel

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dbpick - check arrivels

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ttgrid Compute a travel time grid file step1 Copy paraneter 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 > grid_file step4 Display the grid >displayttgrid grid_file grid_name

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ttgrid.pf Design grid 1 Design grid 2 Deisgn grid 3 Design grid 4 grid name ( remember the grid names and how many grids you have !! )

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displayttgrid (check your grid)

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dbgrassoc dbgrassoc spatial grid search based associator/locator step1 Copy paraneter file on local directory >pfcp dbgrassoc your_directory step2 Edit dbgrassoc.pf>vi dbgrassoc.pf step3 Execute dbgrassoc >dbgrassoc -pf dbgrassoc.pf dbin dbout grid_file

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dbgrassoc.pf define the parameters for each grids in grid_file Put your grid name here !!

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Output files of dbgrassoc db.origin - hypocenter parameters db.event - the preferred origin for an event db.arrival - phase, time of the seismic arrivals db.assoc - connects arrival to origin, list travel time residuals, etc.

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dbloc2 - Interactive hypocenter location >dbloc2 dbname

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Practice !!!