Calculate S wave Receiver Functions (SRF) for single station¶

Version after 1.2.13 has involved functions for SRF calculation. The workflow is similar to PRF calculation.

Materials¶

Users should prepare following materials.

SAC files of teleseismic events including S wave. Refer to RF calculation.
A configure file with the same content with that of PRF. Refer to Calculate PRFs for single station.

Run in command line¶

Similar to the workflow for PRFs, we have provided a command srf for quickly calculating SRFs.

usage: srf [-h] [-l] [-r N|E|NE] [-s] [-b [BAZ]] [-w] [-p] [-i] cfg_file

Calculating RFs for single station

positional arguments:
cfg_file    Path to RF configure file

optional arguments:
-h, --help  show this help message and exit
-l          use local catalog, defaults to false
-r N|E|NE   Reverse components: N, E or NE
-s          Switch the East and North components
-b [BAZ]    Correct back-azimuth. If "baz" is specified, the corr_baz = raw_baz + baz. If there is no argument, the back-azimuth will be corrected with
            minimal energy of T component. The searching range is raw_baz +/- 90
-w          Write project to localfile
-p          Wether or not manually pick arrival time and waveforms arround S phase with a GUI.
-i          Wether grid search incidence angle

Note

Both TRZ and LQT are available for SRF calculation. the Z or L component of RF is deconvolved by R or Q component.

GUI for visual checking S wave¶

Compared with prf, srf has a new option of -p for visual checking seismic waveforms and picking S phase arrival with a GUI:

../_images/srfui.png — GUI for checking SRFs. Black lines denote manually picked arrival time. Red lines denote theoretical arrival time.¶

This GUI is open after arrival time calculation and rotation. The seismic waveforms in 3 components are cut around theoretical S wave arrival time (the red line). A pre-picking is preformed with a STA/LTA method in T component (the black line).
If the current event has a low quality, users can mark the event to “poor” via button mark to poor or hotkey d.
Directly click is used to manually pick S arrival time. The pre-picking line will move to where you click on.

Save checked events to a local file¶

Specified -w allow users to save events, parameters and picked S arrival time into a local pkl file. For re-calculation please load the file in Python script with:

from seispy.rf import RF

rf = RF.loadpjt('path/to/xxx.pkl')
rf.detrend()
rf.filter()
rf.rotate()
rf.trim()
rf.deconv()
rf.saverf()

Visual checking SRFs¶

After calculation, the same step of visual checking as prf can be preformed via pickrf command. See Visual check PRFs with an user interface in detail.

Note

In this scheme, files of *_L.sac in rfpath will be searched in prior, when comp = LQT is set in configure file. If comp = TRZ, files of *_Z.sac will be searched.