Ines Ivančić
description
Transcript of Ines Ivančić
Improvement and Harmonization of BSHAP Earthquake Catalogue
[Compilation of data, comparison with SHARE-GEM catalog]
Ines IvančićCroatian Seismological Survey, Department of
Geophysics, Faculty of Science, University of Zagreb, Zagreb
NATO SfP 984374 | Improvements in the Harmonized Seismic Hazard Maps for the Western Balkan Countries
Unified BSHAP Earthquake CatalogueSummary on previous project - NATO SfP
983054The BSHAP-1 catalog is compiled from:- National catalogues:
Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Hungary, Italy, Montenegro, Macedonia,Romania, Serbia and Slovenia
- Regional and Global catalogues:Karnik 1996; Shebalin & Leydecker; ISC; NEIC; CMT Harvard Catalog; RCMT, INGV, Roma; RCMT, ETHZ, Zurich and EMMA database, Version 2
The initial BSHAP-1 catalogue
38.0 – 47.5 N12.5 – 24.5 E
M ≥ 3.513342 earthquakes
Improvements in the Harmonized Seismic Hazard Maps for the Western Balkan Countries, 2nd Workshop, Belgrade, 24-25 April 2013
Step
Task By Date
1 BSHAP-1 catalogue should be updated by reflecting any change after 2010 (the only update is required by Croatia in this meeting)
Croatia 15 May 2013
2 Finalized BSHAP-1 catalogue should be compared to the ISC-GEM catalogue for large events for any discrepancies
Albania 1 July 2013
3 Updates to the BSHAP-1 catalogue for 3.0≤M<3.5 earthquakes and any earthquakes occurred between 2010-2012 should be put together using 15 km buffer zones around national borders
Croatia 15 August, 2013
4 Neighbors should check the buffer zones and send updates to Croatia
All 1 September,
20135 After the catalogue is finalized, declustering and
completeness check should be performedSerbia 1
November, 2013
6 Method of updating the catalog in the future should be proposed
Macedonia
1 September,
2013
Plan for the WP1:
CROATIA
MONTENEGRO
SERBIA
ALBANIA
MACEDONIA• Albania: 1964-2011, M ≥ 1.0• Croatia: 373BC-2012, M ≥ 3.0• Macedonia:
–479-2005, M ≥ 3.0 catalogue already submitted to BSHAP-1
–2006-2013, M ≥ 3.0 taken from the official Greek Catalogue (Aristotle University of Thessaloniki,http://geophysics.geo.auth.gr/ss/station_index_en.html)
• Montenegro: 1970-2012, M ≥ 3.0
• Serbia: 1970-2012, M ≥ 3.0• Bosnia and Herzegovina: ???
CATALOGUES SUBMITED FOR BSHAP-2
?
According to the agreement: • Update the BSHAP-1
catalogue for 3.0≤M<3.5 earthquakes after 1970
• Merge earthquakes occurred between 2010-2012
• … using 15 km buffer zones around national borders
Bosnia and Herzegovina: • missing catalogue
CATALOGUES SUBMITED FOR BSHAP-2
M≥3.0‘Clipped’ national earthquake catalogues
?
1970 - 2012
BSHAP-1M ≥ 3.5
Bosnia and Herzegovina
BSHAP-1 CATALOGUE (M≥3.5):• B&H participated with its national
catalogue
BSHAP-2 • missing national catalogue for events
3.0≤M< 3.5 after 1970 and events after 2010
• Red dots: BSHAP-1• Blue dots: CEC2012 (Croatian earthquake catalog)
1386 -2010M ≥ 3.5
BSHAP-1 and CEC2012 compared for events M≥3.5, in the period 1386-2010: BSHAP-1: 504 earthquakes CEC2012: 614 earthquakes
• All avaliable data from Croatian, Montenegrin and Serbian catalogues were compiled for BSHAP-2 earthquake catalogue on the teritory of B&H
1386 -2012 M ≥ 3.0
BSHAP-2
FINAL SELECTION FROM THE CATALOGUES SUBMITED FOR BSHAP-1 UPDATE
MERGING BSHAP-2 CATALOGUEPROCEDURE:• Defining duplicate events
in border region (15km)• Removing events
M < 2.4 & M ˃ 4.0 (1970 – 2012)from national catalogues
• Comparing it with BSHAP-1
PROBLEMS:• National catalogues
contain original data for all duplicate events resolved in BSHAP-1
• Because of the possibility to create new duplicates, it was of great importance to determine events previosly resolved in BSHAP-1
CRO
B&H
ALB
MN
MN
• Earthquakes within border region: approx. 15 km from the both sides of the border
• Finding duplicate events between neighbouring countries: Croatia – Monte Negro, Monte Negro – Serbia, Monte Negro – Albania and Serbia - Albania
• Comparing duplicates with BSHAP-1 catalogue: all events resolved in BSHAP-1 catalogue were identified.
• Assigning corresponding country to the event. It was done with the use of MapInfo program and the geographical coordinates in its Europe.tab file. (Possible discrepancies with real border coordinates?)
DEFINING DUPLICATE EVENTS IN BORDER REGION
• T ± 90 s or less?• D ± 40 km or less?• Every doubtful event
should be manually checked?
BSHAP-2 Earthquake Catalogue
38.0 – 47.5 N12.5 – 24.5 E
510BC – 1969M ≥ 3.5
1970 – 2012M ≥ 3.0
19539 earthquakes
BSHAP-2 Earthquake Catalogue – estimating completeness
39.2 – 46.6 N12.8 – 23.3 ETime distribution of seismic
events (mainshocks) by year (1970-2012) , (ML ≥ 3.0)
Magnitude frequency distribution of earthquakes
MC ≥ 4.0 (bML = –1.12)
(max.-likelihood b-value, after Gutenberg-Richter relationship)
Maximum magnitude by year:
Magnitude timeline1970-2012, M ≥ 3.0 (Mw|ML or MLH)(19539 earthquakes)
BSHAP-2 Earthquake Catalogue
Num
ber o
f eq.
per
yea
rM
agni
tude
Count
Gap in magnitude distribution at aprox.
3.5 <M<4.0 due to irregular spatial
distribution of earthquakes with
magnitude M<4.0!
Blue dots: BSHAP-2Red dots: BSHAP-1
Magnitude distribution of mainshocks in narrower area of BSHAP-2 catalogue (9698 eq):
Magnitude distribution of mainshocks in narrower area of BSHAP-2 catalogue (9698 eq):
Magnitude distribution of all earthquakes in narrower area of BSHAP-2 catalogue (9007 eq):
BSHAP-2 catalogue compared to the ISC-GEM catalogue for large events for any discrepancies
38.0 – 47.5 N12.5 – 24.5 E
M ≥ 5.5
http://www.isc.ac.uk/iscgem/index.php
ISC-GEM Global Instrumental Earthquake Catalogue(1900-2009), M ≥ 5.5
ISC-GEM catalogue
Determinig same events:
Green dots: ISC-GEMRed dots: BSHAP-2
ISC
-GEM
BSH
AP-
2
Comparing BSHAP-2 and ISC-GEM
38.0 – 47.5 N12.5 – 24.5 E
M ≥ 5.5
http://www.isc.ac.uk/iscgem/index.php
ISC-GEM Global Instrumental Earthquake Catalogue(1900-2009), M ≥ 5.5
Green dots: ISC-GEMRed dots: BSHAP-2
SHARE European Earthquake Catalogue (SHEECv3.3) 373BC – 2006
http://www.efehr.org:8080/jetspeed/portal/hazard.psml
Grünthal, G., Wahlström, R., Stromeyer, D. (2013), The SHARE European Earthquake Catalogue (SHEEC) for the time period 1900-2006 and its comparison to EMEC. Journal of Seismology
BSHAP-2 catalogue compared to the SHEEC catalogue (SHARE European Earthquake Catalogue (ver. 3.3))
38.0 – 47.5 N12.5 – 24.5 E
BSHAP-2 comparison with SHARE (SHEEC) catalog
Yellow dots: SHARE-GEMRed dots: BSHAP-2
SHEEC38.0 – 47.5 N12.5 – 24.5 E373BC – 2006
M ≥ 3.06609 earthquakes
BSHAPE-238.0 – 47.5 N12.5 – 24.5 E510BC – 2006
M ≥ 3.017614 earthquakes
Time difference
Distance difference
SHEE
CB
SH
AP
E-2
MN
Mwu(BSHAPE-2)
BSHAP-2 comparison with SHARE-GEM (SHEEC) catalogBSHAP-1 – SHEEC compared
magnitude distribution Determining same events:
Magnitude-difference distribution (Mwu-Mw)/Mwu(BSHAP)
Mwu(BSHAPE)/Mw(SHARE) magnitude regression
4052 earthquakes
-0.5≤M≤0.5 87% eq.
CONCLUSIONAccomplished tasks:• Updated BSHAP-2 catalogue with 3.0≤M<3.5
earthquakes and earthquakes occurred between 2010-2012 according to updated national earthquake catalogues
• Determined duplicate events in 15 km buffer zones around national borders
• Updated Bosnia and Herzegovina earthquake catalog with all available data from Croatian, Montenegro and Serbian national catalogues
Tasks to be accomplished:• Neighbors should check buffer zone updates • Declustering and completeness check should be
performed
Proposed tasks:• Updating BSHAP-2 catalogue with 3.0≤M<3.5 events and
events occurred between 2010-2012 from neighboring countries (Italy, Slovenia, Hungary, Romania, Bulgaria and Greece) if possible
• Unification of the magnitudes, especially according to new updates
• Examining and filtering the BSHAP Earthquake Catalogue for missing or duplicate events
And finaly providing a final earthquake catalogue compatible with international standards
CONCLUSION