Where does obspy Wood-Anderson zeros and poles information come from?

Usage Questions
1

Hi,
This question is relevant to anyone trying to compute local magnitudes (Ml) with obspy, or anyone trying to reproduce a Wood-Anderson response.

I was looking at the code of obspy.signal.invsim Wood Anderson zeros and poles, and also at the at the zeros and poles proposed by Bormann and Dewey (2014) and they are not the same.

Where does obspy Wood-Anderson zeros and poles information come from? I would like to know to use the most up-to-date information.

Reference:

Bormann, P., & Dewey, J. W. (2014). The new IASPEI standards for determining magnitudes from digital data and their relation to classical magnitudes. New Manual of Seismological Observatory Practice 2 (NMSOP-2), 1–44. https://doi.org/10.2312/GFZ.NMSOP-2_IS_3.3

2

AFAIR and according to the source code Moritz used as source the New Manual of Seismological Observatory Practice (Version 1). Unfortunately I can’t verify it as I don’t have it anymore. The other possible source which has been mentioned is PITSA. You could also try to contact Yannik Behr.

3

Found it

Bormann, P. (ed.) (2002). IASPEI New Manual of Seismological Observatory Practice (NMSOP), GeoForschungsZentrum Potsdam, ISBN: 3-9808780-0-7, 2 Volumes.

Table 11.3, page 569 in the PDF I found online which I won’t link here.

4

Thank you very much. Problem solved!

Reading both the 2002 and 2014 versions, I cannot discern which is best. I will use the most recent version just because it is better documented.