You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
61 lines
2.0 KiB
ReStructuredText
61 lines
2.0 KiB
ReStructuredText
.. _global_mlh:
|
|
|
|
###
|
|
MLh
|
|
###
|
|
|
|
The MLh plugin (previously MLsed) is designed to compute amplitudes
|
|
and magnitudes according to the Swiss Seismological Service (SED)
|
|
standards.
|
|
|
|
Description
|
|
===========
|
|
|
|
Amplitude
|
|
---------
|
|
|
|
The MLh amplitude calculation is very similar to the original :ref:`ML<global_ml>`.
|
|
The two differences are:
|
|
|
|
- It uses the maximum of the two horizontal components (average can be configured if necessary)
|
|
- It uses zero-to-peak in stead of peak-to-peak values
|
|
|
|
Zero-to-peak is calculated by just dividing the peak-to-peak amplitude by two.
|
|
This is not exact for unsymmetrical signals, but that doesn't matter because the
|
|
code actually generates zero-to-peak amplitudes internally and multiplies them
|
|
with two. So in the end we get real zero-to-peak values.
|
|
|
|
Station Magnitude
|
|
-----------------
|
|
|
|
The MLh plugin calculates the individual station magnitude using the following formula:
|
|
|
|
.. math::
|
|
|
|
mag = \log10(waamp1) + A \times hypdistkm + B
|
|
|
|
waampl is the amplitude produced by the MLh plugin. Hypdistkm is the distance
|
|
from the sensor to the hypocenter in kilometers. A and B are parameters that
|
|
can be configured in a config file. Several pairs of A and B can be configured
|
|
for different ranges of hypocenter distance.
|
|
|
|
* Amplitude unit in SeisComP: **millimeter** (mm)
|
|
* Time window: 150 s by :ref:`scautopick` or distance dependent
|
|
* Distance range: 0 - 20 deg
|
|
* Depth range: 0 - 80 km
|
|
|
|
Network Magnitude
|
|
-----------------
|
|
|
|
To compute the network magnitude from station magnitudes the SED standard is applied
|
|
by computing the median value of all contributing station magnitudes without any trimming.
|
|
|
|
Configuration
|
|
-------------
|
|
|
|
Add the *mlh* plugin to the existing plugins in the global configuration.
|
|
Set the calibration parameters in the global bindings to compute MLh.
|
|
There exist no default configuration. Add MLh to the list of
|
|
amplitudes and magnitudes in the configuration of :ref:`scamp` and :ref:`scmag` for computation
|
|
and in :ref:`scesv` for visibility.
|