MWZ - Strong Motion Vs BB - comparison enquiry

[salichon]

MWZ strong motion vs BB station instrumentations shows discrepancies over a few periods

events as 2020p578726 or 2020p332789 are not relevant for comparison

• [x] List of events of interest Enquire on 2020p480708 M4.9 (June 26) M5 2020p877108 (November 20) "~Close and M>5 " Source: Found in Jess s archive (/M_5/HN_HH/spectral_diff_figs/)

• [x] Isolate if new issue arises and confirmed - andf Check over time and events

• Some discrepancies in the PGA measures BB Vs SM

• Close Events are deep - PGA are relatively small

• Pretty Similar PGV and PSA values whether broadband ot Strong motion derived. as in event https://www.geonet.org.nz/earthquake/technical/2020p877108

  <station code="MWZ" name="MWZ" netid="NZ" insttype="CMG-3ES |   <station code="MWZ" name="MWZ" netid="NZ" insttype="FBA-ES-
  <comp name="10.HHE">                                      |     <comp name="21.HNE">
    <acc value="0.0190037842" flag="0"/>                    |       <acc value="0.0315965025" flag="0"/>
    <vel value="0.0098505423" flag="0"/>                    |       <vel value="0.0112607822" flag="0"/>
    <psa03 value="0.0389111310" flag="0"/>                  |       <psa03 value="0.0374327296" flag="0"/>
    <psa10 value="0.0158798289" flag="0"/>                  |       <psa10 value="0.0156407395" flag="0"/>
    <psa30 value="0.0016790727" flag="0"/>                  |       <psa30 value="0.0016322399" flag="0"/>
  </comp>                                                         </comp>
  <comp name="10.HHN">                                      |     <comp name="21.HNN">
    <acc value="0.0147913790" flag="0"/>                    |       <acc value="0.0270401913" flag="0"/>
    <vel value="0.0084836261" flag="0"/>                    |       <vel value="0.0098948070" flag="0"/>
    <psa03 value="0.0217556314" flag="0"/>                  |       <psa03 value="0.0298586980" flag="0"/>
    <psa10 value="0.0112616010" flag="0"/>                  |       <psa10 value="0.0120955998" flag="0"/>
    <psa30 value="0.0014069534" flag="0"/>                  |       <psa30 value="0.0014836777" flag="0"/>
  </comp>                                                         </comp>
  <comp name="10.HHZ">                                      |     <comp name="21.HNZ">
    <acc value="0.0196288268" flag="0"/>                    |       <acc value="0.0280989366" flag="0"/>
    <vel value="0.0092678665" flag="0"/>                    |       <vel value="0.0092719176" flag="0"/>
    <psa03 value="0.0271926279" flag="0"/>                  |       <psa03 value="0.0283981317" flag="0"/>
    <psa10 value="0.0145067851" flag="0"/>                  |       <psa10 value="0.0148599090" flag="0"/>
    <psa30 value="0.0007866412" flag="0"/>                  |       <psa30 value="0.0007429837" flag="0"/>
  </comp>                                                         </comp>
  </station>                                                      </station>

• Z components are very similar PSA

• Horizontal components are different above ~4Hz "Noise" contribution ?

• [x] - Propose solution / fix /Actions Site effect on the horizontal ? Components slightl;y off between both instruments in 2020 ? Close and relevant Events took for this station are often deep (so mostly above ~~vertical location) Would need to enquire about shallow local and M>4.5 events. if any issues arises clearly

• [ ] - Document

I don't reckon there is a critical or major issue. - to my "quick" check up can be complemented by others ...

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FYI @SquirrelKnight @elidana @mnaguit

[salichon]

2020p480708 June looks legit

[salichon]

• [x] Any other further questions enquiries ?