Hi all,<div> I 've been using broadband data from IRIS on research and recently encounter a confusing thing about response.</div><div>I am using the BH* channels of network AZ, and it should be velocity data. I downloaded sac files from SCEC stp.</div>
<div>I originally request response file in SEED format, then extracted it to be RESP.AZ.XXX..BHX, the response file. </div><div>Recently, because I want to confirm the amplitudes in velocity and also in displacement is correct, I went to IRIS SeismiQuery to get the response file updated until 2011. Surprisingly, the extracted response file from my SEED format and the response file from SeismiQuery are different.</div>
<div>The RDSEED extracted response file has 2 zeros and 5 poles, but the response file from SeismiQuery has 5 zeros 9 poles.</div><div>I thought 2 zeros is standard for velocity response, had no idea what the 5 zeros are. They are from the same time span for same station. </div>
<div><br></div><div>Post front portion of RESP files</div><div>1. from RDSEED:</div><div>=================================</div><div><div># << IRIS SEED Reader, Release 4.7.5 >></div><div># </div>
<div># ======== CHANNEL RESPONSE DATA ========</div><div>B050F03 Station: RDM</div><div>B050F16 Network: AZ</div><div>B052F03 Location: ??</div><div>B052F04 Channel: BHE</div><div>
B052F22 Start date: 2004,056,18:43:30</div><div>B052F23 End date: No Ending Time</div><div># =======================================</div><div># + +--------------------------------------------+ +</div>
<div># + | Response (Poles & Zeros), RDM ch BHE | +</div><div># + +--------------------------------------------+ +</div><div>
# </div><div>B053F03 Transfer function type: A [Laplace Transform (Rad/sec)]</div><div>B053F04 Stage sequence number: 1</div><div>B053F05 Response in units lookup: M/S - velocity in meters per second</div>
<div>B053F06 Response out units lookup: V - emf in volts</div><div>B053F07 A0 normalization factor: 5.91892E+07</div><div>B053F08 Normalization frequency: 0.159155</div>
<div>B053F09 Number of zeroes: 2</div><div>B053F14 Number of poles: 5</div><div># Complex zeroes:</div><div># i real imag real_error imag_error</div>
<div>B053F10-13 0 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00</div><div>B053F10-13 1 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00</div><div># Complex poles:</div><div># i real imag real_error imag_error</div>
<div>B053F15-18 0 -3.701000E-02 3.701000E-02 0.000000E+00 0.000000E+00</div><div>B053F15-18 1 -3.701000E-02 -3.701000E-02 0.000000E+00 0.000000E+00</div><div>B053F15-18 2 -2.513000E+02 0.000000E+00 0.000000E+00 0.000000E+00</div>
<div>B053F15-18 3 -1.310000E+02 4.673000E+02 0.000000E+00 0.000000E+00</div><div>B053F15-18 4 -1.310000E+02 -4.673000E+02 0.000000E+00 0.000000E+00</div></div><div><br></div><div><br></div><div>2. from SeismiQuery</div>
<div>======================================</div><div><br></div><div><div>###################################################################################</div><div>#</div><div>B050F03 Station: RDM</div><div>B050F16 Network: AZ</div>
<div>B052F03 Location: ??</div><div>B052F04 Channel: BHE</div><div>B052F22 Start date: 2000,264,20:11:00</div><div>B052F23 End date: 2001,250,20:49:00</div><div>#</div><div># +-----------------------------------+</div>
<div># | Response (Poles and Zeros) |</div><div># | AZ RDM BHE |</div><div># | 09/20/2000 to 09/07/2001 |</div><div># +-----------------------------------+</div>
<div>#</div><div>B053F03 Transfer function type: A</div><div>B053F04 Stage sequence number: 1</div><div>B053F05 Response in units lookup: M/S - velocity in meters per second</div>
<div>B053F06 Response out units lookup: V - emf in volts</div><div>B053F07 A0 normalization factor: +5.74357E+12</div><div>B053F08 Normalization frequency: +2.00000E-01</div>
<div>B053F09 Number of zeroes: 5</div><div>B053F14 Number of poles: 9</div><div># Complex zeroes:</div><div># i real imag real_error imag_error</div>
<div>B053F10-13 0 +0.00000E+00 +0.00000E+00 +0.00000E+00 +0.00000E+00</div><div>B053F10-13 1 +0.00000E+00 +0.00000E+00 +0.00000E+00 +0.00000E+00</div><div>B053F10-13 2 -1.51500E+01 +0.00000E+00 +0.00000E+00 +0.00000E+00</div>
<div>B053F10-13 3 -3.18600E+02 +4.01200E+02 +0.00000E+00 +0.00000E+00</div><div>B053F10-13 4 -3.18600E+02 -4.01200E+02 +0.00000E+00 +0.00000E+00</div><div># Complex poles:</div><div># i real imag real_error imag_error</div>
<div>B053F15-18 0 -3.70000E-02 +3.70000E-02 +0.00000E+00 +0.00000E+00</div><div>B053F15-18 1 -3.70000E-02 -3.70000E-02 +0.00000E+00 +0.00000E+00</div><div>B053F15-18 2 -1.59900E+01 +0.00000E+00 +0.00000E+00 +0.00000E+00</div>
</div><div>...</div><div><br></div><div><br></div><div>Does anyone know why and how this will affect our final outcome? What are the outputs and will they be consistent?</div><div><br></div><div>Thanks,</div><div><br></div>
<div>--Tien</div>