Rebuilding the Bulletin of the International Seismological Centre (ISC)
Abstract
Currently, the published International Seismological Centre (ISC) locations represent a mixture of algorithms (Reviser, ISCloc), velocity models (Jeffreys-Bullen, ak135), and phases (P-wave only, P&S, and finally all available ak135 phases starting in 2009). Thus, the primary goal of the Rebuild Project is to modernize the ISC bulletin by homogenizing our methods, procedures, and quality standards across more than four decades (1964-2010) of prior relocations at the ISC. We are also incorporating many new historical datasets from both temporary and permanent networks which were not available to us at the time of first relocation. Additionally, event magnitudes are determined in a more robust way - no longer will magnitudes be calculated using only one or two station readings, but instead recomputed with an alpha-trimmed median and requiring a minimum of three station readings. Employing the newest version of the ISC locator (ISCloc, Bondar & Storchak, 2011), all events in the bulletin are relocated using the ak135 global velocity model using all available phases. Then, using an internally developed and tested set of event quality criteria, our team of analysts works carefully with each event that has been flagged as requiring additional review. After each data month has been processed, an updated set of quality checks are run, and any further issues are consequently resolved. Our current predictions indicate that more than 150,000 flagged events will be reviewed by our analysts over the forty-six data-year period of the project. Once the Rebuild Project is finished, the ISC Bulletin will be the most complete and modern database of global seismicity freely available anywhere in the world. At present, we have finished work on sixteen years of historical data (1964-1979), and we show our preliminary results here.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.S53B0665B
- Keywords:
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- 7209 Earthquake dynamics;
- SEISMOLOGY;
- 7215 Earthquake source observations;
- SEISMOLOGY;
- 7221 Paleoseismology;
- SEISMOLOGY;
- 7230 Seismicity and tectonics;
- SEISMOLOGY