Improvement and Harmonization of Serbia Improvement and Harmonization of Serbia BSHAP Earthquake CatalogueBSHAP Earthquake Catalogue

WORKSHOPFOR THE NATO SCIENCE FOR PEACE PROJECT

“HARMONIZATION OF SEISMIC HAZARD MAPS FOR THE WESTERN BALKAN COUNTRIES”Belgrade, Serbia

April, 25 – 26 2013

• The first stage in the preparation of a new Seismic The first stage in the preparation of a new Seismic Hazard Map is preparation of the earthquake Hazard Map is preparation of the earthquake catalogue.catalogue.

• Since the publication of the Catalogue for Balkans in Since the publication of the Catalogue for Balkans in 1974 many earthquake catalogs have been published, 1974 many earthquake catalogs have been published, but they are mainly compilations of primary sources, but they are mainly compilations of primary sources, without verification of the main parameters.without verification of the main parameters.

• Extensive investigations have been conducted in Extensive investigations have been conducted in recent years to revise available catalogs using large recent years to revise available catalogs using large number of internal catalogs which are combination of number of internal catalogs which are combination of parametric catalogs and authentic data on parametric catalogs and authentic data on earthquakes and their effects, as well as using bulletin earthquakes and their effects, as well as using bulletin data published by ISC, EMSC and seismic networks in data published by ISC, EMSC and seismic networks in region.region.

• The data for the earthquake catalog preparation The data for the earthquake catalog preparation can be classified into three time periods, which can be classified into three time periods, which differ in accuracy and data sources:differ in accuracy and data sources:

• I.I. Historical period (up to 1893);Historical period (up to 1893);• II.II. Early instrumental period (1983-1970); Early instrumental period (1983-1970); • III.III. Instrumental period (1970-up to now).Instrumental period (1970-up to now).• The diversity of the data sources and techniques of The diversity of the data sources and techniques of

earthquake location, evident in those three periods, earthquake location, evident in those three periods, had for its consequence differences in the level of had for its consequence differences in the level of accuracy of all main parameters.accuracy of all main parameters.

• We came to the conclusion that it is necessary to We came to the conclusion that it is necessary to verify and re-interpret events in National catalog, verify and re-interpret events in National catalog, especially strong earthquakes with intensities >= 6.especially strong earthquakes with intensities >= 6.

I Historical period (before 1893)I Historical period (before 1893)

• The earliest information on earthquakes in Serbia are dating The earliest information on earthquakes in Serbia are dating from 1456. from 1456. Earthquakes in this period have unreliable Earthquakes in this period have unreliable geographic coordinates because of poor records based on which geographic coordinates because of poor records based on which they were located. Their seismic intensity was defined mostly they were located. Their seismic intensity was defined mostly based on small number of poorly defined data, while the depth based on small number of poorly defined data, while the depth of their hypocenters remained unknown. of their hypocenters remained unknown.

• These earthquakes only represent evidence of the seismic These earthquakes only represent evidence of the seismic activity in the area and a qualitative definition of energy levels. activity in the area and a qualitative definition of energy levels. Locations of the epicenters are useful base for seismic zone Locations of the epicenters are useful base for seismic zone delineation.delineation.

• Since 1879 Golubac - Moldova Noua earthquake, the collection Since 1879 Golubac - Moldova Noua earthquake, the collection and systematization earthquake effects significantly increased. and systematization earthquake effects significantly increased. Those data were the basis Those data were the basis for the assessment of earthquake for the assessment of earthquake intensities, intensities, macroseismic magnitudes and depths acording to macroseismic magnitudes and depths acording to intensity distribution.intensity distribution.

II Early instrumental period (1893-II Early instrumental period (1893-1970)1970)

• Macroseismic data base of strong earthquakes for this Macroseismic data base of strong earthquakes for this period together with instrumentally recorded data, offered period together with instrumentally recorded data, offered a reliable basis for the assessment of eq parameters with a reliable basis for the assessment of eq parameters with sufficient accuracy.sufficient accuracy.

• Instrumentally recorded earthquakes from this period were Instrumentally recorded earthquakes from this period were relocated using seismic models calculated for the territory relocated using seismic models calculated for the territory of Serbia, while their magnitudes were redefined using all of Serbia, while their magnitudes were redefined using all available data. Hypocenter depths were calculated and available data. Hypocenter depths were calculated and verified comparing them with the distribution of macro verified comparing them with the distribution of macro seismic effects in relocation procedure. seismic effects in relocation procedure.

• For the strongest events which occurred on the territory of For the strongest events which occurred on the territory of Serbia, in the procedure of earthquake intensity Serbia, in the procedure of earthquake intensity redefinition, all available newspaper and other reports and redefinition, all available newspaper and other reports and photos were used, including seismic ground deformations. photos were used, including seismic ground deformations. European Macroseismic Scale criteria for intensity European Macroseismic Scale criteria for intensity assessment were applied and vulnerability class of the assessment were applied and vulnerability class of the buildings in the observed time periods was also taken into buildings in the observed time periods was also taken into account.account.

Preparation of the catalogue, 1893-Preparation of the catalogue, 1893-19701970

Available data sourcesAvailable data sources

– Macro seismic parametric catalogue: Catalogue of Macro seismic parametric catalogue: Catalogue of earthquakes, Part I, Part II, UNDP-earthquakes, Part I, Part II, UNDP- UNESCO Survey of UNESCO Survey of the Seismicity of the Balkan Region, 1974;the Seismicity of the Balkan Region, 1974;

– Earthquake Catalogue for Central and Southeastern Europe 342 BC - 1990 AD, 1998 (Shebalin, Leydecker, 1998)

– Isoseismic mapsIsoseismic maps– Macro seismic earthquake catalogue in Seismological Macro seismic earthquake catalogue in Seismological

Survey of Serbia and other studies of earthquakes Survey of Serbia and other studies of earthquakes – Primary historical sources (photographs, Primary historical sources (photographs, witness witness

descriptions in magazines, otherdescriptions in magazines, other))

• The first catalog prepared for The first catalog prepared for the Balkans was well known the Balkans was well known UNESCO/UNDP Project UNESCO/UNDP Project “Survey of the Seismicity of “Survey of the Seismicity of the Balkan Region”, edited in the Balkan Region”, edited in 1974. 1974.

• In the catalogue, earthquake In the catalogue, earthquake magnitudes were calculated magnitudes were calculated from intensity distribution.from intensity distribution.

• Estimation of intensities were Estimation of intensities were based on values expressed in based on values expressed in various macro seismic scales. various macro seismic scales. Intensity scales were not Intensity scales were not adequately recalculated, so adequately recalculated, so that intensities of all strong that intensities of all strong earthquakes were mostly earthquakes were mostly overrated.overrated.

For a historical and early instrumental period, Catalogue and early instrumental period, Catalogue for Central and Southeastern Europe (1998) is relevant. for Central and Southeastern Europe (1998) is relevant. Magnitudes in this catalog are Magnitudes in this catalog are Ms and mbMs and mb, , determined determined using macro seismic and other data, using macro seismic and other data, 308 of 321 events 308 of 321 events with M>=3 in Catalog are before 1990with M>=3 in Catalog are before 1990

Magnitudes: 130 events are MS, Macrosismique and Magnitudes: 130 events are MS, Macrosismique and mixed determinations (rough estimation of MS from mixed determinations (rough estimation of MS from observed I max and supposed depth included) with observed I max and supposed depth included) with error code :error code :

• b = ± 0.3b = ± 0.3• c = ± 0.5c = ± 0.5• d = ± 0.7d = ± 0.7• e = ± 1.0e = ± 1.0• f = ± 1.5f = ± 1.5• 129 events are MS, Direct measurements with error 129 events are MS, Direct measurements with error

code :code :• k = ± 0.5k = ± 0.5• l = ± 0.7l = ± 0.7Coordinate determination: most events are macroseismic Coordinate determination: most events are macroseismic

determinationsdeterminationsAnalysis catalog led to the conclusion that it should be Analysis catalog led to the conclusion that it should be

revisedrevised

Preparation of the cataloguePreparation of the catalogue historical and early instrumental period (1879-1970)historical and early instrumental period (1879-1970)

• The assessment procedure of the parameters for The assessment procedure of the parameters for strong historical earthquakes has been applied to strong historical earthquakes has been applied to earthquakes for the period 1879 - 1970. earthquakes for the period 1879 - 1970.

• Intensities were re-estimated using original Intensities were re-estimated using original description of the effects: 1.003 out of 5.188 events description of the effects: 1.003 out of 5.188 events with Io>=5 from original macro seismic catalog with Io>=5 from original macro seismic catalog recorded up to 1970 are checked and processedrecorded up to 1970 are checked and processed

• Epicenters were relocated using local Epicenters were relocated using local seismotectonic modelsseismotectonic models

• Based on area within isoseismic areas, earthquake Based on area within isoseismic areas, earthquake parameters - magnitude and focal depth were parameters - magnitude and focal depth were assessed.assessed.

VIII-IX

1893 Svilajnac earthquake 1893 Svilajnac earthquake is one of the best is one of the best documented with data documented with data collected in the field and collected in the field and obtained from the local obtained from the local reports reports

Old Isoseismal Map of the Old Isoseismal Map of the 1893 Svilajnac Earthquake1893 Svilajnac Earthquake

Photos show the effects on buildings and in soil in 1893 Photos show the effects on buildings and in soil in 1893 Svilajnac earthquakeSvilajnac earthquake

In the Monograph “Earthquakes in Serbia in 1893” geologists In the Monograph “Earthquakes in Serbia in 1893” geologists Jovan Zujovic and Djordje Stanojevic described in detail Jovan Zujovic and Djordje Stanojevic described in detail efects obtained on the field immediately after the efects obtained on the field immediately after the earthquake.earthquake.

Photos show typical buildings in Serbia in the end of 19. century.Photos show typical buildings in Serbia in the end of 19. century.

Vulnerability class of most buildings in epicentral area is A and B – Vulnerability class of most buildings in epicentral area is A and B – fieldstone, earth brick, simple stone. Within the first isoseismal fieldstone, earth brick, simple stone. Within the first isoseismal area, it was observed that many buildings class B had 3. area, it was observed that many buildings class B had 3. degree damages and a few 4. degree. Many buildings class A degree damages and a few 4. degree. Many buildings class A had 4. degree damages and few 5. degree.had 4. degree damages and few 5. degree.

“BONDRUK”-vulnerability class B Adobe brick-vulnerability class A

Lokacija Lat N Lon E Ii

Troponje 44.160 21.270 8Subotica 44.150 21.340 8Medvedja 44.166 21.350 8Gladna 44.083 21.300 8Vel. Popo 44.116 21.350 8Svilajnac 44.233 21.200 8Grabovac 44.180 21.210 8Sedlari 44.183 21.290 8Vlaska 44.000 21.350 7Lapovo 44.166 21.100 7Bobova 44.233 21.250 7Savac 43.850 21.366 7Orasje 44.366 21.083 7Vel. Plana44.500 21.050 7Djurinac 44.233 21.350 7Zabari 44.366 21.166 7Jagodina 44.000 21.233 7Kupinovac44.200 21.316 7Salakovac 44.566 21.283 7M. Crnice 44.550 21.283 7Dvoriste 44.100 21.533 7

Based on classification in EMS scale Based on classification in EMS scale intensity 8-9 was assessed in epicentral intensity 8-9 was assessed in epicentral area. Following the same procedure, area. Following the same procedure, intensities 7, 6, 5 were assigned. intensities 7, 6, 5 were assigned.

Magnitude assessment is based on:

Checking M from available catalogsConsidering liquefaction phenomena (5.7-5.9) Using Musson equation for I=3, I=4 areaChecking our equation for I=5 area.

Isoseismal Map of the 1893 Svilajnac Earthquake Isoseismal Map of the 1893 Svilajnac Earthquake

According to the area affected According to the area affected with particular intensity and using with particular intensity and using intensity attenuation relation,intensity attenuation relation,

Ii=1.3786 M - 3.243 D + 3.4019Ii=1.3786 M - 3.243 D + 3.4019

magnitude 5.8 and 8 km depth magnitude 5.8 and 8 km depth was estimated.was estimated.

Distribution of highest seismic intensity within first isoseismal is one of the most important information about seismotectonics in epicentral area and wider seismic zone which is important for seismic hazard calculation.

III Instrumental period (1970-up to III Instrumental period (1970-up to now)now)

• As the number of seismological station increased As the number of seismological station increased and was accompanied by a constant improvement and was accompanied by a constant improvement of the quality of recorded dataof the quality of recorded data

• Large high-quality data base was accumulated and Large high-quality data base was accumulated and as a consequence made it possible to work on as a consequence made it possible to work on various seismological research, such as defining various seismological research, such as defining regional seismic and seismotectonic models. regional seismic and seismotectonic models.

• Extensive studies have been conducted in recent Extensive studies have been conducted in recent years to revise earthquake catalog by making use years to revise earthquake catalog by making use of numerous internal catalogs (combination of of numerous internal catalogs (combination of parametric catalogs and authentic earthquake data parametric catalogs and authentic earthquake data and their effects), as well as the bulletin data and their effects), as well as the bulletin data published by ISC, EMSC and seismic networks in published by ISC, EMSC and seismic networks in region.region.

• 1970-1990: 457 events M>=3 checked and/or 1970-1990: 457 events M>=3 checked and/or processed Number of eq`s increased ~50% processed Number of eq`s increased ~50% comparing to Shebalins catalog.comparing to Shebalins catalog.

Preparation of the cataloguePreparation of the catalogue

All available data are processed in program “Potres” using All available data are processed in program “Potres” using most reliable data most reliable data Local and regional velocity models are used and tested to Local and regional velocity models are used and tested to fit the best solution and minimum correction.fit the best solution and minimum correction.Example is numerical processing of 1927 Rudnik Example is numerical processing of 1927 Rudnik earthquake, M=5.9, Io=8 which is recorded at 63 stations earthquake, M=5.9, Io=8 which is recorded at 63 stations all over the world.all over the world.

prg LOKACIJA, Seizmicki model: SR1, M = 5.9, Io = 8.8 MCS

+----------------------------------------------------------------+

¦ D A T U M HIPOC.VRIJEME LAT (N) LON (E) Z(km) GAP ¦

¦ 15.05.1927. 2:47:10.95 44.186 21.319 11.2 73 ¦

¦ stand.dev. +/- 4.36 0.082 0.187 11.9 Nst=51¦

¦----------------------------------------------------------------¦

¦ +------- P-faza ------+ +----- S-faza -----+ ¦

¦-stn--delta--h--m---s----rez.--tez.-----m--s-----rez.--tez.---az¦

¦ BEO 99 2:47:30.00 2.67 2.63 47:40.00 0.23 2.63 316¦

¦ SAR 234 47:45.00 -3.07 2.30 261¦

¦ MST 297 47:55.00 -0.82 2.16 252¦

¦ BUD 408 48:10.00 0.45 1.89 48:46.00 -7.75 1.53 334¦

¦ ZAG 458 48:13.00 -2.77 1.77 49:14.00 9.35 1.49 294¦

¦ GRA 559 48:25.00 -3.36 1.53 49:33.00 6.31 1.46 305¦

¦ LJU 573 48:34.00 4.01 1.48 291¦

¦ VKA 595 48:31.00 -1.82 1.44 50: 5.00 30.48**0.00 320¦

¦ PMP 678 48:35.00 -8.11 0.96 49:30.00-22.54**0.00 236¦

¦ NPL 689 48:48.00 3.60 1.21 49:48.00 -6.80 1.07 237¦

¦ ATH 719 48:55.00 6.87 1.09 164¦

¦ VEN 724 48:52.00 3.20 1.14 50:17.00 14.48 0.22 281¦

¦ RDP 752 48:49.00 -3.24 1.07 50: 8.00 -0.53 1.07 249¦

¦ FIR 809 49: 0.00 0.74 0.93 50:20.00 -0.83 0.93 267¦

¦ INN 845 49: 0.00 -3.74 0.82 50:25.00 -3.68 0.82 294¦

¦ CHE 943 49:14.00 -1.95 0.61 50:51.00 0.93 0.61 314¦

¦ RAV 991 49:22.00 0.10 0.50 51: 8.00 7.50 0.46 294¦

¦ ZUR 1052 49:25.00 -4.44 0.34 51:14.00 0.29 0.35 290¦

¦ HOH 1057 49:27.00 -3.11 0.34 51:16.00 1.11 0.34 298¦

¦ MNC 1085 50:22.00 48.45**0.00 275¦

¦ POT 1098 49:42.00 6.89 0.23 51:21.00 -2.65 0.24 326¦

¦ FEL 1109 49:50.00 13.52 0.08 292¦

¦ STR 1152 49:37.00 -4.77 0.11 51:38.00 2.68 0.12 295¦

¦ KNG 1186 50:16.00 29.98**0.00 51:39.00 -3.76 0.03 357¦

¦ GRN 1243 49:56.00 2.86**0.00 52:10.00 14.76**0.00 275¦

¦ HAM 1329 50: 7.00 3.29**0.00 52:20.00 6.24**0.00 321¦

¦ MKY 1358 50:17.00 9.70**0.00 53: 2.00 41.95**0.00 72¦

¦ COP 1429 50:15.00 -1.19**0.00 52:40.00 4.38**0.00 333¦

¦ UCC 1474 50:18.00 -3.79**0.00 52:51.00 5.57**0.00 300¦

¦ DBN 1489 50:24.00 0.36**0.00 53: 4.00 15.33**0.00 306¦

¦ PAR 1534 50:26.00 -3.16**0.00 52:59.00 0.65**0.00 290¦

¦ FBR 1600 50:35.00 -2.37**0.00 53: 6.00 -6.73**0.00 259¦

¦ KSA 1708 50:58.00 7.28**0.00 54: 2.00 25.88**0.00 132¦

¦ BDB 1713 50:49.00 -2.41**0.00 266¦

¦ ALG 1754 50:52.00 -4.41**0.00 53:48.00 1.92**0.00 242¦

¦ UPP 1762 50:59.00 1.53**0.00 53:52.00 4.06**0.00 352¦

¦ HEL 1797 51: 6.00 4.28**0.00 53:57.00 1.60**0.00 8¦

¦ KEW 1811 51: 1.00 -2.51**0.00 53:57.00 -1.53**0.00 297¦

¦ HLW 1823 51: 4.00 -1.01**0.00 54: 6.00 4.84**0.00 151¦

¦ PUL 1841 51: 7.00 -0.20 0.00 54:15.00 10.02**0.00 20¦

¦ LNN 1857 51: 9.00 -0.27 0.00 54:18.00 9.39**0.00 19¦

¦ OXD 1884 51: 4.00 -8.59**0.00 54:21.00 6.57**0.00 297¦

¦ TIF 1936 51:24.00 5.01**0.00 98¦

¦ ALI 1939 51:42.00 22.67**0.00 55:14.00 47.76**0.00 250¦

¦ BID 2064 50:25.00-69.90**0.00 53:50.00-63.53**0.00 300¦

¦ TLO 2153 51:35.00-10.86**0.00 55: 7.00 -5.72**0.00 257¦

¦ ALM 2170 51:38.00-10.05**0.00 55:11.00 -5.57**0.00 248¦

¦ EDI 2187 51:31.00-19.18**0.00 55:12.00 -8.29**0.00 307¦

¦ MAL 2334 51:56.00-12.39**0.00 55:11.00-41.20**0.00 249¦

¦ SFS 2496 52: 9.00-19.46**0.00 56:11.00-16.35**0.00 250¦

¦ TAS 3941 54:13.00-74.51**0.00 59:51.00-110.06**0.00 95¦

¦----------------------------------------------------------------¦

¦ Epicentar lociran na: 100 km JUGOISTOCNO od BEOGRADA ¦

¦ ili na: 11 km JUGOISTOCNO od SVILAJNCA ¦

+----------------------------------------------------------------+

Earthquake Catalogue Earthquake Catalogue M>=3.5M>=3.5

~ ~ about 320 about 320 earthquakes Io>=6 earthquakes Io>=6 with epicenters in with epicenters in the territory of the territory of Serbia are Serbia are processed for processed for BSHAP IBSHAP I

Earthquake Catalogue Earthquake Catalogue M>=3.0M>=3.0

>880 earthquakes >880 earthquakes Io>=5 Io>=5 in macroseismic catalog in macroseismic catalog are are processed for processed for BSHAP II, BSHAP II, ~600 events ~600 events in total are added to in total are added to CatalogCatalog

~4.560 events with Io=3-~4.560 events with Io=3-4 in macroseismic 4 in macroseismic catalog to be checked, catalog to be checked, many of them having many of them having usefull informations usefull informations which enables which enables assessment of assessment of magnitude and focal magnitude and focal depthdepth

Unification of the magnitude scales

• For a historical and early instrumental period and early instrumental period magnitudes magnitudes Ms and Mb are used are used

• For strongest instrumentally recorded earthquakes, For strongest instrumentally recorded earthquakes, magnitude magnitude Mlh Mlh is oftenis often determined, which determined, which corresponds corresponds to Mw magnitude for magnitude range 5=<M=<8to Mw magnitude for magnitude range 5=<M=<8. .

• For the period between For the period between 1963 and 20051963 and 2005, the catalogue , the catalogue consists of the earthquakes re-assessed acording to ISC consists of the earthquakes re-assessed acording to ISC data in which data in which MMbb and M and Ms and Mlhs and Mlh for the strong for the strong earthquakes (from Wiechert and Mainka seismograms) are earthquakes (from Wiechert and Mainka seismograms) are published. published.

• Since 2005, magnitude ML have been determined for the have been determined for the earthquakes in Serbia. earthquakes in Serbia.

• Using 180 earthquakes with Ms/mb pairs in ISC Catalog, the Using 180 earthquakes with Ms/mb pairs in ISC Catalog, the relation for magnitude conversion is defined.relation for magnitude conversion is defined.

• Ms=1.263(+/-0.054)mb-1.505(+/-0.244), for the magnitude range 3.5=<mb=<6.1.

• Makroseismic magnitudes Mm ,M, Ms,up to 1970 are converted to unified Mw using the Scordilis relations, ~50% of those occurred before 1971, ~30% of all Mw unified are calculated based on Scordilis relations