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FOZ issue with broadband vs. accelerometer comparison #86

Closed SquirrelKnight closed 2 years ago

SquirrelKnight commented 2 years ago

Similar to station RIZ, FOZ shows a time-dependent issue, most likely due to flattening of one of the two sensors. pSA_diff_FOZ_datetime

The events used for these computations are as follows:

'2020p111984', '2020p201743', '2020p475488', '2020p606562', '2802756', '2808300', '2829153', '2853545'

elidana commented 2 years ago

our team had a look at FOZ installation history, below their findings. Since 2004 the same broadband (CMG-3ESP) and strong motion (FBA-ES-T) sensors have been installed and always co-located in a vault side by side. In 2015 the vault was moved. Orientations of the installed sensors in each vault epoch looks all good (see pictures below).

@SquirrelKnight can you please confirm what is the event that does not show an homogeneous difference across the spectrum? (should be one from the group '2802756', '2808300', '2829153', '2853545')

2004

FOX_vault

2015

P1010801

salichon commented 2 years ago

from above "FOZ - sugarloafquarry is causing me a bit of confusion as a 4X is currently present there since 2017 (= I expect a problem) yet Jesse's plots for 2020 events shows a 1:1 ratio " (--> thought to be the opposite)

salichon commented 2 years ago

FOZ metadata history: https://service.geonet.org.nz/fdsnws/station/1/query?station=FOZ&format=text&level=channel&channel=H?Z

#Network | Station | Location | Channel |  Elevation | Azimuth | Dip | SensorDescription | Scale | ScaleFreq | ScaleUnits | SampleRate | StartTime | EndTime
NZ|FOZ|10|HHZ|0.000000|0.000000|-90.000000|Broadband Seismometer|838860800.000000|1.000000|m/s|100.000000|2004-10-13T00:00:00|2015-09-22T18:00:00
NZ|FOZ|20|HNZ|0.000000|0.000000|-90.000000|Accelerometer|427336.117780|1.000000|m/s**2|200.000000|2004-10-13T00:00:02|2015-09-24T23:59:59
NZ|FOZ|11|HHZ|0.000000|0.000000|-90.000000|Broadband Seismometer|838860800.000000|1.000000|m/s|100.000000|2015-09-23T05:30:00|2017-03-14T21:20:00
NZ|FOZ|21|HNZ|0.000000|0.000000|-90.000000|Accelerometer|427336.117780|1.000000|m/s**2|200.000000|2015-09-25T00:00:00|2017-03-14T21:20:00
NZ|FOZ|21|HNZ|0.000000|0.000000|-90.000000|Accelerometer|427336.117780|1.000000|m/s**2|200.000000|2017-03-14T21:20:01|2017-03-15T23:59:59
NZ|FOZ|11|HHZ|0.000000|0.000000|-90.000000|Broadband Seismometer|838860800.000000|1.000000|m/s|100.000000|2017-03-14T21:20:01|2018-12-11T21:00:00
NZ|FOZ|21|HNZ|-0.000000|0.000000|-90.000000|Accelerometer|1709344.471122|1.000000|m/s**2|200.000000|2017-03-16T00:00:01|
NZ|FOZ|11|HHZ|0.000000|0.000000|-90.000000|Broadband Seismometer|838860800.000000|1.000000|m/s|100.000000|2018-12-11T21:45:00|
salichon commented 2 years ago

events to be looked at in more detaills

Each season has SM and BB set up differently

salichon commented 2 years ago
  1. season 1 (only 2008 event) PGA/PGV values very consistent from one instrum,ent to another: 
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>         <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<!DOCTYPE earthquake SYSTEM "stationlist.dtd">                  <!DOCTYPE earthquake SYSTEM "stationlist.dtd">
<stationlist created="" xmlns="ch.ethz.sed.shakemap.usgs.xml"   <stationlist created="" xmlns="ch.ethz.sed.shakemap.usgs.xml"
  <station code="FOZ" name="FOZ" netid="NZ" insttype="CMG-3ES |   <station code="FOZ" name="FOZ" netid="NZ" insttype="FBA-ES-
    <comp name="10.HHE">                                      |     <comp name="20.BNE">
      <acc value="0.0323674290" flag="0"/>                    |       <acc value="0.0327546128" flag="0"/>
      <vel value="0.0402220914" flag="0"/>                    |       <vel value="0.0406699982" flag="0"/>
      <psa03 value="0.0851590240" flag="0"/>                  |       <psa03 value="0.0758072721" flag="0"/>
      <psa10 value="0.0393508916" flag="0"/>                  |       <psa10 value="0.0386904403" flag="0"/>
      <psa30 value="0.0139519885" flag="0"/>                  |       <psa30 value="0.0139745425" flag="0"/>
    </comp>                                                         </comp>
    <comp name="10.HHN">                                      |     <comp name="20.BNN">
      <acc value="0.0471940290" flag="0"/>                    |       <acc value="0.0468957958" flag="0"/>
      <vel value="0.0311889867" flag="0"/>                    |       <vel value="0.0319635127" flag="0"/>
      <psa03 value="0.1137600603" flag="0"/>                  |       <psa03 value="0.1137505145" flag="0"/>
      <psa10 value="0.0324292424" flag="0"/>                  |       <psa10 value="0.0323447519" flag="0"/>
      <psa30 value="0.0082503008" flag="0"/>                  |       <psa30 value="0.0082962589" flag="0"/>
    </comp>                                                         </comp>
    <comp name="10.HHZ">                                      |     <comp name="20.BNZ">
      <acc value="0.0262786899" flag="0"/>                    |       <acc value="0.0267345734" flag="0"/>
      <vel value="0.0356911684" flag="0"/>                    |       <vel value="0.0357763512" flag="0"/>
      <psa03 value="0.0484587420" flag="0"/>                  |       <psa03 value="0.0479322373" flag="0"/>
      <psa10 value="0.0395912395" flag="0"/>                  |       <psa10 value="0.0399410097" flag="0"/>
      <psa30 value="0.0134465935" flag="0"/>                  |       <psa30 value="0.0134981134" flag="0"/>
    </comp>                                                         </comp>
  </station>                                                      </station>
</stationlist>                                                  </stationlist>
salichon commented 2 years ago

Season 2 2020 : Obvious difference! 0.25 ratio as for other OBSIDIAN4x - CMG/Q330 and FBA/Obsidian4x [since 2017]

salichon commented 2 years ago

@elidana @SquirrelKnight relates to https://github.com/GeoNet/help/issues/85

And points all the attention to the Datalogger Obsidian4x response or internal configuration

elidana commented 2 years ago

https://github.com/GeoNet/delta/pull/1234

salichon commented 2 years ago

is addressed through Obsidian4X response e afaik and will be documented in https://github.com/GeoNet/help/issues/94 @SquirrelKnight any other concerns about FOZ ?