1. Data Collection in Africa
Blessing Shumba, Dmitry A. Storchak, James Harris, Domenico Di Giacomo
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2. Intro: ISC Products and Services
not real time
aimed at quality, not a speed of delivery
long-term
continuous
most complete
open to all
designed for use by researchers
Station Registry (with USGS)
ISC Bulletin (including the EHB)
Reference Event (GT) List (with IASPEI)
ISC-GEM Catalogue
Event Bibliography
Seismological Contacts
John Milne
Harold Jeffreys
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3. Intro: ISC data products: www.isc.ac.uk
update the front-page with the current one
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4. 1: International Seismograph Station Registry (IR)
Since 1970s, the ISC maintains the Registry jointly with NEIC / USGS
~22,000 stations, open or closed, are registered in IR;
parameters of ~550 were registered or modified in 2015.
We are preparing a meaningful set of agency codes that will resemble the commonly used institutional acronyms such as: CGS (instead of PRE), MSDZ (instead of BUL), NRIAG (instead of HLW), ...
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5. 1st AfSC Assembly, Luxor-Aswan, Egypt
2: ISC Bulletin ( )
The definitive and most complete long-term record of global earthquake information
Contains major source parameters of ~5.8 million seismic events: natural and anthropogenic
~137 agencies report bulletin data to be included into the ISC Bulletin.
Individual agency bulletins in different formats are parsed, checked, merged per natural event, event parameters re-calculated, reviewed and made available in standard formats.
5.8 M events, 1.9 M of them reviewed, 148 M seismic arrivals, 98 M in reviewed
137 agency-contributors
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6. 1st AfSC Assembly, Luxor-Aswan, Egypt
2: ISC Bulletin
Growth of event & phase data volume continues
Worldwide, the ISC Bulletin is more complete than either of NEIC or IDC
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7. Log scale; in red are those events/arrivals added in 2015
2: ISC Bulletin
Log scale; in red are those events/arrivals added in 2015
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8. 2: ISC Bulletin : Focus in Africa
The red dots show events that have been recomputed by the ISC and have an ISC hypocenter.
The blue dots shows events that are in the ISC Bulletin but their locations are fixed to hypocenter solutions of local agencies
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9. 1964-Present Annual ISC hypocentres in Africa
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10. 2: ISC Bulletin 1964-Present Annual hypocenters received at the ISC
PRE, South Africa
BUL, Zimbabwe
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11. 2: ISC Bulletin 1964-Present Annual hypocenters received at the ISC
SPGM,Morocco
CNRM, Morocco
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12. 2: ISC Bulletin 1964-Present Annual hypocenters received at the ISC
ESASWARG
TUN,Tunisia
HLW,Egypt
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13. 1st AfSC Assembly, Luxor-Aswan, Egypt
The 2 figures above shows the stations and agencies in Africa which contribute to the MS(ISC) & mb(ISC) for any event globally
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14. 1st AfSC Assembly, Luxor-Aswan, Egypt
Magnitude plots for events in Africa
The Machaze, Mozambique, Mw=7.0 aftershock sequence
The Bourmedes, Algeria, Mw = 6.8 aftershock sequence
The Lake Tanganyika, Mw=6.8 aftershock sequence
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15. Magnitude for events in Africa (1964-present)
The red dots show events that have been recalculated by ISC and have an ISC hypocenter.
The blue dots show events that are fixed to any hypocenter and do not have an ISC solution
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16. 1st AfSC Assembly, Luxor-Aswan, Egypt
2: ISC Bulletin
The ISC Bulletin contains arrival times of many different types of seismic waves, including those predicted by the ak135 velocity model
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17. 2: ISC Bulletin : Reviewed 2003 Zemmouri – Boumerdes Earthquake

18. Hypocentre solutions from 20 agencies with the ISC Solution as the prime hypocentre;
39 Magnitude values reported for this event from 22 Agencies.
58 published papers under ISC event Bibliography

19. 2: ISC Bulletin: August 5, 2014, South Africa, Orkney Earthquake,
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20. 2: ISC Bulletin: August 5, 2014, South Africa, Orkney Earthquake…Cont…..
As of today, the automatic ISC Bulletin contains:
hypocentre solutions from 12 agencies;
23 Magnitude type reported for this event
1 published paper
More data for this event is still coming to the ISC

21. 2: ISC Bulletin: Rebuild
Existing BAAS, ISA, ISS Catalogues
Existing ISC Bulletin
Present
no phase data;
no reliable magnitudes
2002
2006
2009
1904
1964
JB: P
JB:P&S
ak135:P&S
ak135: all phases
different location methods, phase types and Earth’s velocity models used over 100 years
Reviser
ISCloc:RL
ISCloc:IB
+ Additional station data of permanent and temporary networks
+ ISC-GEM station data
Rebuilt ISC Bulletin
station data first time,
many new surface wave
magnitudes
1904
1964
1978
2009
Present
many new surface wave magnitudes
bulletin parameters computed with the new ISC location method and ak135 velocity model
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22. 1st AfSC Assembly, Luxor-Aswan, Egypt
2: ISC Bulletin: EHB ( )
The EHB dataset is a groomed subset of the ISC Bulletin with well recorded seismic events relocated using (Engdahl et al, 1998) technique
The EHB contains arrival times of the most prominent and well reported types of seismic waves
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23. 3: IASPEI Reference Event List, GT (1959-2012)
8,573 GT(0-10) events with locations known with 95% confidence level:
natural
anthropogenic
accompanied by ~870,000 associated seismic arrivals
The list is maintained by the ISC under the supervision of IASPEI
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24. 4: ISC-GEM Catalogue (1900-2012)
The ISC-GEM Global Instrumental Earthquake Catalogue is built for the purpose of seismic hazard and risk assessment:
~24,500 homogeneous hypocentre locations and MW estimates
with the estimates of uncertainty
covering 110 years period
prepared using uniform location and magnitude determination techniques,
using original seismogram measurements
: MW≥7.5 worldwide + smaller shallow events in stable continental areas
: MW≥6¼
: MW≥5.5
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25. 5: ISC-GEM Catalogue, large data entry effort
The work on the ISC-GEM Catalogue required digitising of a large volume of data that has not been available electronically in the past.
(Storchak et al., 2014)
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26. 1st AfSC Assembly, Luxor-Aswan, Egypt
Extension Project
Earthquake Numbers
Jan 2013, Ver 1.0
Jan 2015, Ver 2.0
Earthquake Numbers
Jan 2016, Ver 3.0
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27. 5: ISC Event Bibliography (1904-2016)
An interactive web-search for references to scientific articles related to seismic events in a particular region and period of occurrence/publication;
includes articles in many fields of Geosciences;
seismic events include both earthquakes and anthropogenic events.
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28. 5: ISC Event Bibliography (1904-2016)
~17,000 scientific articles related to ~14,000 events in ~500 journal titles;
articles published in the last ~60 years and
related to seismic events occurred in the last ~110 years;
a few events in the first half of the 20th century;
(Di Giacomo et al., 2014)
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29. 5: ISC Event Bibliography
1,118 scientific articles related to 1,343 events that occurred in the last 110 years were added during calendar year 2015
in addition to recent scientific periodicals, this number includes many articles in the specially processed back issues of BSSA, SRL and 30 volumes of “Earthquakes in the USSR”.
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30. 5: ISC Event Bibliography: Africa Region
1981 November 14, Aswan, Egypt Earthquake
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31. CTBTO Link to the ISC Database
The Link is a service provided to NDCs and PTS from the secure IDC website.
The ISC designs, implements and maintains this service in consultation with the IDC.
The Link is funded and technically assisted by CTBTO.

32. The Link: Overview of searches
Four groups of searches:
● Area based – spatio-temporal searches within the ISC Bulletin;
● REB event based – spatiotemporal searches based on specific events within the IDC Reviewed Event Bulletin;
● IMS station based – searches of station data proximate to a particular IMS seismic station.
● GT event based – searches for GT event waveform records.

33. ISC Members and Sponsors
62 Member-Institutions from 45 countries provide annual financial support to the ISC, including Egypt, Algeria and South Africa.
There is also a number of international, public and commercial entities that support specific ISC projects:
Innovate UK
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34. 1st AfSC Assembly, Luxor-Aswan, Egypt
Summary
ISC continues with its unique long-term international mission collecting and integrating seismic bulletin data from 137 agencies worldwide
ISC Products are openly available:
Int. Station Registry ( )
ISC Bulletin ( ), including the EHB ( )
GT ( )
ISC-GEM Catalogue ( )
ISC Event Bibliography ( )
Seismological Contacts
These products and services provide a multitude of information related to recent earthquakes such as the Orkney, South Africa earthquake and the 2015 Lake Tanganyika
The ISC appreciates the financial support of its Members and Sponsors in Africa: NRIAG (Egypt), CRAAG (Algeria) and CGS (SA).
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