Yield

The yield of explosions can be computed from magnitudes. The computation is provided by the yield plugin.

Station yield

The station yield values are computed from mb station magnitudes by:

mb = A * log_{10}(yield) + B

where A and B can be configured in yield section of the gobal bindings configuration.

  • yield unit: kilotons (kt)

  • original magnitude: mb

Network yield

By default, the trimmed mean is calculated from the station magnitudes to form the network yield. To stabilize the network magnitudes the smallest and the largest 12.5% of the station yield values are are removed before calculating the network yield.

Setup

Make yield computations available:

  • Add the yield plugin to the existing plugins in the global configuration:

    plugins = ${plugins}, yield
    
  • Add a magnitude type profile named “yield” in the global bindings configuration with A and B corresponding to the multiplier A and the offset B, respectively.

    Default values are considered from Ringdahl et al. 1992 1.

Reference

A

B

Geographic area

application

Ringdal et al., 1992 1

0.75

4.45

North America and Central Asia

nuclear explosion

Murphy, 1981 2

0.81

3.92

Nevada Test Site (NTS)

nuclear explosion

Compute yield automatically:

  • For automatic computation of yield, add yield to the amplitudes in scamp 3 and to the magnitudes in scmag 4.

  • The yield should not be used to compute summary magnitudes by scmag 4. Add yield to summaryMagnitude.blacklist in the configuration of scmag, scmag.cfg, to ignore yield when computing the summary magnitude.

References

1(1,2)

Ringdal, F., P. D. Marshall, and R. W. Alewine (1992), Seismic yield determination of Soviet underground nuclear explosions at the Shagan River test site, Geophys. J. Int., 109(1), 65–77.

2

Murphy J.R. (1981), P Wave Coupling of Underground Explosions in Various Geologic Media. In: Husebye E.S., Mykkeltveit S. (eds) Identification of Seismic Sources — Earthquake or Underground Explosion. NATO Advanced Study Institutes Series (Series C — Mathematical and Physical Sciences), vol 74. Springer, Dordrecht

3

https://docs.gempa.de/seiscomp/4/current/apps/scamp.html

4(1,2)

https://docs.gempa.de/seiscomp/4/current/apps/scmag.html