Batch calculation and CCP stacking#

Calculate PRFs of a seismic array in batch#

This example provide a procedure for batch calculating PRFs of NCISP-III array (Zheng et al., 2007)

Download this example#

Download link: ex-batrf.tar.gz

Download and unzip the file to any directory.

wget https://osf.io/xghrk/download -O ex-batrf.tar.gz
tar -xzf ex-batrf.tar.gz

The package include Data.ZX with 47 sub folders named as network.station, which include sac files cut out from 300 s after origin time to 1000 s after origin time seismic events. The SACHeader` of station information (``netwk, stnm, stla and stlo) had been written into sac files.

Write a script for batch calculation#

Seispy has provided a command as setpar, which will modify values in the .cfg file. Combining with a list of station information with 3 columns (staname, stla, stlo), We can use the setpar and prf command in shell script (run.sh) for RF calculation in batch. In this example, please execute run.sh in ex-batRF directory for the batch calculation.

while read staname stla stlo
do
    setpar rf.cfg path datapath ./Data.ZX/$staname
    setpar rf.cfg path rfpath ./RFresult/$staname
    prf rf.cfg
done < sta.lst
  • The sta.lst includes station information.

  • The rf.cfg is the configure file. In addition to the datapath and rfpath, other parameters can be set in advance.

  • If set up a local catalog, the calculation time will be saved.

CCP stacking along a linear seismic array#

Download this example#

Download link: ex-ccp.tar.gz

Download and unzip the file to any directory.

wget https://osf.io/hzq2x/download -O ex-ccp.tar.gz
tar -xzf ex-ccp.tar.gz

This package include:

  • A Folder with PRFs (RFresult)

  • A configure file with cfg format (ccp.cfg).

Time-to-depth conversion#

specify following parameters in the ccp.cfg for time-to-depth conversion

  • rfpath: Path to PRFs

  • depthdat: Output data structure after time-to-depth conversion

  • stalist: The list of station information with 3 columns (staname, stla, stlo)

Then execute follow command to do the conversion

rf2depth ccp.cfg

After the time-to-depth conversion, the RFdepth.mat will be generated following the path set as depthdat.

CCP stacking#

specify following parameters in the ccp.cfg for CCP stacking. See Stack PRFs with Common Conversion points (CCP) method in detail.

  • stackfile: Output file for the CCP stacking

  • stack_sta_list: Stations used for the CCP stacking. In this example, we use the same stations as the stalist.

  • Section [bin] for parameters of stacking bins

  • Section [line] for location of the profile.

  • Section [stack] for Depth samples.

Then execute following command for CCP stacking

ccp_profile ccp.cfg -t

An text file set by stackfile will be generated including 6 columns: bin_lat, bin_lon, bin_distance, depth, amplitude and stack_num.

Plot the stacking image#

Seispy dose not provide any functions or script for plotting stacking image. Here we provide a script with GMT6 format for plotting the image. Just run in ex-ccp directory.

sh ps_profile.sh
profile

CCP stacking along the seismic array#

Reference#

Zheng T, Chen L, Zhao L, et al. Crustal structure across the Yanshan belt at the northern margin of the North China Craton[J]. Physics of the Earth and Planetary Interiors, 2007, 161(1-2): 36-49.