Amplitudes/Magnitudes: Regionalization, Aliases, Mw¶

You will …

Regionalize magnitudes.
Create new amplitude and magnitude types as aliases from other amplitudes and magnitudes.
Map magnitudes to the moment magnitude, Mw.

Pre-requisites for this tutorial:

Read the concepts section on magnitudes.
Real-time data for the station must be available locally. See Get real-time data from a remote Seedlink server (single station) or Add real-time stations from GEOFON.
Inventory must be loaded locally.

Afterwards/Results/Outcomes:

Regionalized amplitudes and magnitudes
New amplitude and magnitude types as aliases
Moment magnitudes

Time range estimate:

60 minutes

Regionalization¶

By regionalization, amplitudes and magnitudes can be computed depending on the region of the source or source-receiver pairs. Regions are defined by polygons in BNA or GeoJSON files which must be known to SeisComP.

Amplitudes¶

Measuring amplitudes only for sources or pairs of sources and stations in specific regions is possible by regionalization. The region polygons are defined by magnitude regionalization. In order to use the feature, regionalized amplitudes and magnitudes must have the same type (name) and regionalization must be activated per amplitude type in amplitude-type profiles of global bindings.

Magnitudes¶

With regionalization magnitudes can be computed with region-dependent parameters. If magnitude regionalization is configured but a source or source-station pairs are not considered, no magnitude of the corresponding type is computed.

Setup¶

The procedure to set up magnitude regionalization is:

Create one file which contains the polygons surrounding the regions within which magnitude parameters shall apply. The polygon files are provided in BNA or GeoJSON format and located as set out in the documentation of map layers. The file can be created from any SeisComP GUI application providing maps, e.g., scmv.
For the desired magnitude type create a magnitude-type profile in global module configuration. The name of the profile matches the name of the magnitude, e.g., MLc for the MLc magnitude.
Configure the magnitudes.MLc.regionFile parameter with the full path and name of the polygon file created above.
Within the magnitude-type profile create one or more magnitude-region profile(s) for defining the regionalized parameters applied to the region(s). The name of a profile corresponds to the name of the polygon contained in the polygon file to which the parameters shall apply. Use world for all regions not covered by any polygon.
Configure the regionalized magnitude parameters of the magnitude-region profile. Activate the enable parameter if you wish to apply this profile.
Restart the data processing:
```
seiscomp restart
```
or execute a GUI module.

Important

Parameters which can be configured along with regionalization assume defaults from global binding parameters but override global bindings parameters when configured.
Once regionalization is active, magnitudes for events outside the defined region(s) will not be computed. For considering such events add another magnitude-region profile with the name “world”. Magnitudes for events outside any other magnitude-region profile will then be computed according to this profile.

Setup: station corrections¶

Magnitude station corrections can also be applied in case of reBy regionalization, magnitudes can be computed with region-dependent properties. Regions are defined by polygons in BNA or GeoJSON files which must be known to SeisComP.gionalization. Simply add the names of the magnitude-region profile along with the correction parameter to the original parameter in global module configuration, global.cfg, for the respective magnitude type and station. Use comma separation for multiple regions and colon for separating the region name from the value.

Example for correcting MLv computed at station GE.UGM:

module.trunk.GE.UGM.magnitudes.MLv.offset = 0.1, europe:0.2, asia:-0.1

Note

The configuration of parameters starting with module.trunk. is not supported by scconfig. All corresponding configurations must be done by directly editing the configuration file, e.g., seiscomp/etc/global.cfg.

Application¶

When configured, regionalization is automatically applied when computing magnitudes in scmag or scolv.

Testing¶

Regionalization:
1. Start scolv with the option --debug and load an event of interest
```
scolv --debug
```
2. Relocate the event for generating a new origin.
3. Compute magnitudes selecting the magnitude of interest.
4. Inspect the computed magnitudes in the Magnitude tab of scolv or read the debug output listing the considered magnitudes and stations along with the regionalized parameters.

Amplitude Aliases¶

Amplitude aliases are new amplitude types based original ones. Such aliases allow their specific configuration and computation. They can be created and independent of magnitudes by scautopick and scamp and used for magnitude aliases.

Note

Amplitude aliases make use of the same parameter structure as the initial amplitude but the parameters must be configured independently.

Setup¶

Global module configuration: Define the alias name in amplitudes.aliases.

Format and example:
```
amplitudes.aliases = alias:original amplitude type
amplitudes.aliases = MLc01:MLc
```
Configure the amplitude bindings parameters. The parameters are identical to those of the original amplitude type except that the name of the original magnitude must be replaced by the name of the alias. You may thus first configure the original amplitude and then replace the name.

Example binding configuration for MLc01 derived from MLc:
```
amplitudes.MLc01.preFilter = BW(3,0.5,12)
amplitudes.MLc01.applyWoodAnderson = true
...
amplitudes.MLc01.enable = true
amplitudes.MLc01.enableResponses = false
amplitudes.MLc01.minSNR = 1.5
amplitudes.MLc01.signalBegin = -1
amplitudes.MLc01.signalEnd = min(tt(S) + 10, 150)
...
amplitudes.MLc01.maxDepth = 50
```
Repeat the action for all applicable binding profiles.

Instead of adjusting the bindings profiles you may add the configuration to global or any other module configuration by prepending module.trunk.[module] where [module] is to be replaced by the name of the module including global.

Example global module configuration in global.cfg:
```
module.trunk.global.amplitudes.MLc01.preFilter = BW(3,0.5,12)
module.trunk.global.amplitudes.MLc01.applyWoodAnderson = true
...
module.trunk.global.amplitudes.MLc01.enable = true
module.trunk.global.amplitudes.MLc01.enableResponses = false
module.trunk.global.amplitudes.MLc01.minSNR = 1.5
module.trunk.global.amplitudes.MLc01.signalBegin = -1
module.trunk.global.amplitudes.MLc01.signalEnd = min(tt(S) + 10, 150)
...
module.trunk.global.amplitudes.MLc01.maxDepth = 50
```
Configuration of bindings profiles has the advantage that the parameters are available on any client connected to the messaging including external SeisComP systems. Writing to global module configuration may be more simple than maintaining multiple bindings profiles but the configuration is not available to clients in external computers/SeisComP systems.

Application¶

For automatic measurement by scautopick or scamp add the alias name to the list of measured amplitudes in the corresponding module configuration.
For using the measured amplitude value with magnitudes, create a magnitude alias.

Testing¶

Compute amplitudes with scamp or by magnitude aliases in scolv and read the debug log output as when testing magnitude aliases.

Magnitude Aliases¶

Magnitude aliases are new magnitude types based original ones. Such aliases allow their specific configuration and computation. They can be created from magnitude and amplitude types native in SeisComP or from amplitude aliases which must be defined first. Unless specified explicitly, the amplitude type is the base amplitude of the original magnitude. Other amplitude types or amplitude aliases must be defined first and given explicitly.

Note

Magnitude aliases make use of the same parameter structure as the initial magnitude but the parameters must be configured independently.

Setup¶

Create a magnitude alias in global.cfg by configuring magnitudes.aliases.

Format:
```
magnitudes.aliases = alias:original magnitude type[:amplitude type]
```
The amplitude type is optional and can be omitted when equal to the type of the original magnitude.

Example for an alias magnitude, MLc1, derived from the MLc magnitude and amplitude. Since initial amplitudes and magnitudes are identical, the amplitude type can be dropped:
```
magnitudes.aliases = MLc01:MLc:MLc
magnitudes.aliases = MLc01:MLc
```
Example for an alias magnitude, MLc1, derived from the MLc magnitude and amplitude. Since initial amplitudes and magnitudes are different, the amplitude type must be given and configured independently
```
magnitudes.aliases = MLc01:MLc:MLc01
```
Configure the alias amplitude if any is used.
Configure the alias magnitude in either way:
- Adjust binding profiles: Configure global bindings parameters by directly adjusting binding profiles.
  
  Parameters of original magnitudes which are supported by magnitude-type profiles can be set for the magnitude alias in scconfig by creating a new magnitude-type profile having the name of the magnitude alias.
  
  All other parameters must be written to the binding parameter files using an external text editor:
  1. Read the relevant parameter names of the original magnitude from global binding, e.g., in scconfig or the binding parameter file. Parameter names must include the full hierarchy including all sections. Example for parameter name of original magnitude:
    magnitudes.MLc.parametric.c1
  2. Edit all relevant binding parameter files, e.g., seiscomp/etc/key/global/profile_HHZ in a text editor and set the values for the alias magnitude. For default values, the parameters do not need to be set.
    
    Example of resulting parameter for alias magnitude MLc01:
    magnitudes.MLc01.parametric.c1 = 0.6
- Regionalization: Set up by regionalization.
  - Consider the tutorial above on magnitude regionalization.
  - For the name of new magnitude-type profiles now use the new alias name.
Hint

When initially configuring amplitude and magnitude aliases, scconfig does not know which original amplitude and magnitude types are considered and the corresponding parameters may not be accessible. The full list of parameters of the alias can, however, be derived from original types:
1. Open scconfig and configure the original amplitude and magnitude referenced by the alias.
2. Close scconfig.
3. Open the binding or module configuration file, e.g., seiscomp/etc/key/global/profile_HHZ or global.cfg.
4. Copy or rename the name of the referenced amplitude or magnitude in the parameters to the name of the alias.
5. Open scconfig. The new parameters are now visible along with the original one and can be adjusted. You may now remove all irrelevant parameters of the original magnitude.
This procedure applies to the adjustment of binding profiles and to regionalization except that regionalization only supports magnitudes.
- Write bindings parameters to global module configuration: Manually adjust the module configuration file, e.g., global.cfg. The operation is not supported by scconfig.
  1. Read the relevant parameter names of the original magnitude from global binding, e.g., in scconfig. The names must include the full hierarchy including all sections. Example:
    magnitudes.MLc01.parametric.c1
  2. Open the module configuration file, e.g., seiscomp/etc/global.cfg in a text editor.
  3. Prepend module.trunk.global. to the parameter name and add it along with its value to the configuration file for all networks and stations. Example:
    module.trunk.global.magnitudes.MLc01.parametric.c1 = 0.7
    For a given network or network and station replace global by the network or the network and the station code. Example for network CX and station PB01:
    module.trunk.CX.PB01.magnitudes.MLc01.parametric.c1 = 0.7 module.trunk.CX.magnitudes.MLc01.parametric.c1 = 0.7
  4. Add the new magnitude name to the configuration of all relevant modules, e.g., scamp, scmag, scevent, scolv.
  Note
  
  The parameters starting with module.trunk. are not available for configuration in scconfig.
  Warning
  
  Binding parameters configured in global module configuration should only be considered exceptionally. These parameters will
  - Override the corresponding parameters configured by regionalization using the region world.
  - Not be written to the database and cannot be accessed by SeisComP modules running on other computers.

Application¶

For automatic computation by scmag add the alias name to the list of measured magnitudes in the corresponding module configuration.
For interactive computation choose the magnitude alias name in scolv when computing magnitudes. The alias may be added to the default magnitudes in the scolv module configuration.

Testing¶

Start scolv with the option --debug and load an event of interest
```
scolv --debug
```
Relocate the event for generating a new origin.
Compute magnitudes selecting the magnitude of interest including the new alias.

Inspect the computed magnitudes in the Magnitude tab of scolv or read the debug output listing the considered magnitude names and aliases along with the considered parameters and their values. Example where MLc1 is derived from MLc with a modified maximum depth:

...
30:46 [debug] GE.UGM: MLc1: effective correction (no locale) = 1.00:0.00
30:46 [debug] Parameters for magnitude MLc1
30:46 [debug]   + maximum depth: 50.000 km
30:46 [debug]   + distance mode: hypocentral
30:46 [debug]   + minimum distance: -1.000 km
30:46 [debug]   + maximum distance: 889.561 km
...

Moment Magnitudes¶

All magnitudes, Mx, can be mapped to a moment magnitude, Mw(Mx) by piecewise linear interpolation.

Warning

Do not map mB or Mwp to Mw since this is hardcoded already and done automatically by scmag.

Setup¶

The configuration procedure is:

Set up a magnitude-type profile for the original magnitude type in global module configuration. Use scconfig for creating the profile.
Configure the parameter MwMapping, which will become available along with the new profile, e.g., magnitudes.MLc.MwMapping. Alternatively, add the parameter to seiscomp/etc/global.cfg. The parameter is configured as a list of sample points of a piecewise linear function mapping from the original magnitude, Mx, to Mw(Mx). Example for Mw(MLc) based on MLc:
```
magnitudes.MLc.MwMapping = MLc_0:Mw(MLc)_0,MLc_1:Mw(MLc)_1,...,MLc_N:Mw(MLc)_N
```
Any magnitude value outside the configured range is ignored.

The new moment magnitudes will be available along with the original magnitudes and can be viewed in scolv or scesv and considered by scmag or scevent.

In order to avoid that summary magnitudes are computed from original magnitudes and mapped Mw together and biased to both, the original magnitudes can be blocklisted in scmag (summaryMagnitude.blacklist).

Application¶

Mapped Mw() magnitudes are automatically computed when configured.
For consideration in summary magnitudes configure and run scmag.
For consideration in preferred magnitudes configure and run scevent or select in scolv.
For interactive computation choose the original magnitude name in scolv when computing magnitudes.

Amplitudes/Magnitudes: Regionalization, Aliases, Mw¶

Regionalization¶

Amplitudes¶

Magnitudes¶

Setup¶

Setup: station corrections¶

Application¶

Testing¶

Amplitude Aliases¶

Setup¶

Application¶

Testing¶

Magnitude Aliases¶

Setup¶

Application¶

Testing¶

Moment Magnitudes¶

Setup¶

Application¶

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