2011 Antelope Workshop 2011-03-15 中央研究院地球科學研究所 台灣地震科學中心

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