Calculate Background QC Statistics

Use the Calculate Background Database QC Stats option (Geosoft.uxo.gxnet.dll(Geosoft.GX.UXO.UxaBackgroundStats;Run)*) to calculate statistics that can be used to quality control the background measurement data.

ClosedExpand to see the locations (menus) where this option is available.

UX-Analyze extension:

  • AGC Static Data > Sensor Tests and QC Tools
  • AGC Expert User > Static Data Prep and QC

Calculate Background QC Statistics dialog options

Validated background location databases prefix

Select the prefix for the validated background location databases.

Script Parameter:UXANALYZE.BKGSTATS_VALIDATEDDBPREFIX

Maximum distance to validate background location

When a validated background location database is selected, specify the maximum distance that a background measurement can be away from a validated location.

Script Parameter:UXANALYZE.BKGSTATS_MAX_BKG_VALIDATED_DISTANCE

Background databases prefix

Select the prefix for the background measurement databases (e.g., SBG, SRB).

Script Parameter:UXANALYZE.BKGSTATS_DBPREFIX

Group name

Select the background group name.

Script Parameter:UXANALYZE.BKGSTATS_TARGETGROUP

Background Id channel

Select the background Id channel.

Script Parameter:UXANALYZE.BKGSTATS_TARGETID

Mask channel

Select the background mask channel.

Script Parameter:UXANALYZE.BKGSTATS_TARGETMASK

QC mask channel

Select the QC mask channel.

  • QC mask channel will be set to DUMMY if any of the tests fails.

    • Script Parameter:UXANALYZE.BKGSTATS_TARGETMASK2

    Sensor data channel

    Select the data channel.

    Script Parameter:UXANALYZE.BKGSTATS_SENCHAN

    Low gate

    Select the low gate to be used to calculate the difference sum channel.

    The list is populated with the numbers 0 to the maximum gate number minus one. The maximum gate is the same the array size of the Data channel.

    Default value is the 2nd quintile.

    Script Parameter:UXANALYZE.BKGSTATS_LOGATE

    High gate

    Select the low gate to be used to calculate the difference sum channel.

    The list is populated with the numbers 0 to the maximum gate number minus one. The maximum gate is the same the array size of the Data channel.

    Default value is the 4th quintile.

    Script Parameter:UXANALYZE.BKGSTATS_HIGATE

    Location (group) Id channel

    Specify the location ID channel.

    The background measurement that falls within the distance tolerance will have the same location ID. Statistical values are calculated between the background points that have the same location ID, see applications notes.

    If a validated background location database is selected, the same location id’s will be used. Otherwise, location id’s will be generated, starting ID is 1, the first time this tool is used. This channel gets updated each time the tool is executed.

    Default channel name is UXA_BG_LOCATION

    Script Parameter:UXANALYZE.BKGSTATS_LOCATIONID

    Grouping distance tol. (m)

    Specify the search distance that is used to find the background measurements that fall within a group.

    Default value is 1 metre

    Script Parameter:UXANALYZE.BKGSTATS_LOCATION_TOLERANCE

    GPS fix quality

    Select the GPS fix quality, which can be from 0 to 8.

    Default value is 4.

    Script Parameter:UXANALYZE.BKGSTATS_GPSFIXQ

    Output summary file name

    Select the file name for the output CSV file. The default name is based on the latest acquisition time and date.

    Script Parameter:UXANALYZE.BKGSTATS_OUTPUTNAME

    Application Notes

    This tool is run on all the selected measurements in the background database.

    After it has finished processing, the following channels are created/updated in the background ‘target’ database:

    ChannelDescription
    UXA_MaskQCSummary of the QC test results. Measurements that pass are 1, those that fail a dummy (*). This channel then can be used to exclude poor quality data in subsequent processing (i.e. background leveling).
    UXA_DIFFERENCE_MINMinimum value of [SensorDataChannel]_difference_sum
    UXA_DIFFERENCE_MAXMaximum value of [SensorDataChannel]_difference_sum
    UXA_DIFFERENCE_MEANAverage value of [SensorDataChannel]_difference_sum
    UXA_DIFFERENCE_MEDIANMedian value of [SensorDataChannel]_difference_sum
    UXA_DIFFERENCE_STDStandard deviation value of [SensorDataChannel]_difference_sum
    UXA_BG_LOCATIONLocation id value, for that background location. If a Validated Background Location database is selected, that location id will be used.
    UXA_FLATLINED_FLAGFlat lined Rx test, a dummy if pass, a 1 if failed. This channel can be used to filter only failing measurement, for example when you create Decay QC Plots.
    UXA_SATURATED_FLAGSaturated Rx test, a dummy if pass, a 1 if failed. This channel can be used to filter only failing measurement, for example when create Decay QC Plots.
    UXA_CURRENT_FLAGTx current test, a dummy if pass, a 1 if failed. This channel can be used to filter only failing measurement, for example when create Decay QC Plots.
    UXA_GPS_FLAGGPS test, a dummy if pass, a 1 if failed.
    UXA_IMU_FLAGIMU test, a dummy if pass, a 1 if failed.
    UXA_LOCATION_PER_VALBKG_FLAGLocation offset test between background and validated background location; a dummy if pass, a 1 if failed. Should be less than half of the sensor width.
    UXA_DIFF_VALBKG_PERSUMSum of the absolute value of UXA_DIFF_VALBKG divided by the maximum of the absolute value of the validated background location measurement
    UXA_DIFF_VALBKG_PERSUM_FLAGUXA_DIFF_VALBKG_PERSUM value test; a dummy if pass, a 1 if failed. Should be less than 100%
  • Refer to Survey Database QC for more information on how the following channels are calculated: UXA_FLATLINED_FLAG, UXA_SATURATED_FLAG, UXA_CURRENT_FLAG, UXA_GPS_FLAG, and UXA_IMU_FLAG.

    • After the dialog has finished processing, the following channels are created/updated in the background ‘data’ database:

    ChannelDescription
    [SensorDataChannel]_medianMedian of the sensor data channel over all the selected lines
    [SensorDataChannel]_stdevStandard deviation of the sensor data channel over all the selected lines
    [SensorDataChannel]_differenceDifference of the sensor data channel and the median
    [SensorDataChannel]_difference_sumAbsolute difference between the sensor data channel and median, summed up from low to high gate
    UXA_DIFF_VALBKGDifference between the background measurement and validated background location measurement, calculated for the selected low/early gate

    The boundary limits can be found in "uxa.config", which can be located in C:\Program Files\Geosoft\Desktop Applications \etc folder:

    • <backgroundQcStats>
    • <gps multiplier="3" distanceMin="10000" />
    • <imu pitchMin="-30" pitchMax="30" rollMin="-30" rollMax="30" yawMin="-180" yawMax="360" multiplier="3" />
    • <validatedDifference minAbsoluteValue="0.01" thresholdInPercent="100" />
    • <txCurrent minMultipler="0.98" />
    • <flatLinedRxData lowerBound =" 0.02" nSuccessiveDiffMultipler="0.25" />
    • </backgroundQcStats>

    *The GX tool will search in the "gx" folder. The GX.Net tools, however, are embedded in the Geosoft.uxo.gxnet.dll located in the bin folder. If running this GX interactively, bypassing the menu, first change the folder to point to the bin folder, then supply the GX.Net tool in the specified format.

    See Also: