Search:
wiki:pz-files
Last modified 14 months ago Last modified on 07/18/12 12:49:07

# How to Make .pz files for use in localmag, gmew, etc.

Artist: Dr. Stephen R. McNutt

## Obtain Dataless Seed Volume

Sources:

- IRIS BUD: ​http://www.iris.edu/bud_stuff/bud/bud_start.pl?BUDDIR=/budnas/virtualnets/ALL
- Geofon WebDC: ​http://webdc.eu/arclink/query?sesskey=ea8effeb

## Install rdseed

The following instructions are specific to Ubuntu.

Install Dependencies:

     sudo apt-get install cmake
     sudo apt-get install g++-multilib
     sudo updatedb

Download rdseed: ​http://www.iris.edu/forms/rdseed_request.htm

Unpack tar ball:

     tar -xvf rdseed...tar.gz
     cd rdseed...

Compile it:

     make

troubles? see README

## Run rdseed

     ./<rdseed_directory>/rdseed -pf <dataless_file>

"An important fact to note about the SAC PZ output is that acceleration and velocity responses are converted to displacement to conform to the SAC convention." -rdseed manual (included with distribution)

NOTE: Poles and Zeros outputted in radians. Constant in counts/meters. Earthworm requires radians and counts/nanometers, respectively.

Enter file(s) entitled e.g., SAC_PZs_CX_HMBCX_BHZ2007.320.00.00.00.0000_2599.365.23.59.59.99999

    * **********************************
    * NETWORK   (KNETWK): CX
    * STATION    (KSTNM): HMBCX
    * LOCATION   (KHOLE):
    * CHANNEL   (KCMPNM): BHZ
    * CREATED           : 2012-07-17T19:30:36
    * START             : 2007-11-16T00:00:00
    * END               : 2599-12-31T23:59:59
    * DESCRIPTION       : Plate Boundary Station HMBCX, Chile
    * LATITUDE          : -20.278220
    * LONGITUDE         : -69.887910
    * ELEVATION         : 1152.0
    * DEPTH             : 0.0
    * DIP               : 0.0
    * AZIMUTH           : 0.0
    * SAMPLE RATE       : 20.0
    * INPUT UNIT        : M
    * OUTPUT UNIT       : COUNTS
    * INSTTYPE          : Streckeisen STS-2/N
    * INSTGAIN          : 1.500000e+03 (M/S)
    * COMMENT           : N/A
    * SENSITIVITY       : 6.291450e+08 (M/S)
    * A0                : 6.007700e+07
    * **********************************
    ZEROS   3
            +0.000000e+00   +0.000000e+00
            +0.000000e+00   +0.000000e+00
            +0.000000e+00   +0.000000e+00
    POLES   5
            -3.700400e-02   +3.701600e-02
            -3.700400e-02   -3.701600e-02
            -2.513300e+02   +0.000000e+00
            -1.310400e+02   -4.672900e+02
            -1.310400e+02   +4.672900e+02
    CONSTANT        +3.779715e+16

## Make pz file

Confirm the INPUT UNIT is M (meters) [NOTE: CONSTANT given in counts/meter] and then cp from ZEROS to CONSTANT and paste in your Earthworm response file directory (e.g., /opt/earthworm/osopdata/params/responses/) a file entitled, e.g., HMBCX_BHZ_CX.pz:

Now convert the numbers to nm by subtracting 9 units to the exponent (to convert counts/meters to counts/nanometers, 1 m = 1E9 nm so we must DIVIDE by 1E9):

counts/meter = meter/1E9 nanometer = counts/nanometer

    ZEROS   3
            +0.000000e+00   +0.000000e+00
            +0.000000e+00   +0.000000e+00
            +0.000000e+00   +0.000000e+00
    POLES   5
            -3.700400e-02   +3.701600e-02
            -3.700400e-02   -3.701600e-02
            -2.513300e+02   +0.000000e+00
            -1.310400e+02   -4.672900e+02
            -1.310400e+02   +4.672900e+02
    CONSTANT        +3.779715e+07

Additional Resources

- ​http://vps.isti.com/trac/ew/wiki/localmag, see section entitled "Response File Example"
- Scherbaum, F. (2007) Of Poles and Zeros: Fundamentals of Digital Seismology (Modern Approaches in Geophysics)
- Youtube "Z-Domain- Pole and Zero plots": ​http://www.youtube.com/watch?v=m5TP2uG_O2M&feature=relmfu
- Youtube "Z-Domain- 3d View": ​http://www.youtube.com/watch?v=mELFJIZ9cEY&feature=relmfu
- ​http://www.ee.up.ac.za/main/_media/en/undergrad/subjects/eli220/polezero.pdf
- Poles and Zeros GUI: ​http://www.osop.com.pa/?page_id=121

### Attachments

- 739px-Calibration.jpg​ (86.6 KB) - added by branden 14 months ago.

### Download in other formats:

- Plain Text