scamp

scamp measures several different kinds of amplitudes from waveform data. It listens for origins and measures amplitudes in time windows determined from the origin. The resulting amplitude objects are sent to the “AMPLITUDE” messaging group. scamp is the counterpart of scmag. Usually, all amplitudes are computed at once by scamp and then published. Only very rarely an amplitude needs to be recomputed if the location of an origin changes significantly. The amplitude can be reused by scmag, making magnitude computation and update efficient. Currently, the automatic picker in SeisComP 3, scautopick, also measures a small set of amplitudes (namely “snr” and “mb”, the signal-to-noise ratio and the amplitude used in mb magnitude computation, respectively) for each automatic pick in fixed time windows. If there already exists an amplitude, e.g. a previously determined one by scautopick, scamp will not measure it again for the respective stream. Amplitudes are also needed, however, for manual picks. scamp does this as well. Picks with weight smaller than 0.5 in the corresponding Origin are discarded.

Amplitudes for the following magnitudes are currently computed:

MLv

Local magnitude calculated on the vertical component using a correction term to fit with the standard ML.

MLsed

Local amplitude calculated on the horizontals. See MLsed.

mb

Narrow band body wave magnitude using a third order Butterworth filter with corner frequencies of 0.7 and 2.0 Hz. Note that this amplitude is also computed by scautopick for all automatic picks.

mB

Broad band body wave magnitude.

Mw(mB)

Estimation of the moment magnitude Mw based on mB.

Note that in order to be used by scmag, the names of the various magnitude types must match exactly.

Options

TODO config options here.