WORKSHOP
FOR THE NATO SCIENCE FOR PEACE PROJECT
“HARMONIZATION OF SEISMIC HAZARD MAPS FOR THE WESTERN BALKAN COUNTRIES”
Belgrade, Serbia
April, 25 – 26 2013
Improvement and Harmonization of Serbia BSHAP
Earthquake Catalogue
• The first stage in the preparation of a new Seismic
•
•
Hazard Map is preparation of the earthquake catalogue.
Since the publication of the Catalogue for Balkans in
1974 many earthquake catalogs have been published,
but they are mainly compilations of primary sources,
without verification of the main parameters.
Extensive investigations have been conducted in recent
years to revise available catalogs using large number of
internal catalogs which are combination of parametric
catalogs and authentic data on earthquakes and their
effects, as well as using bulletin data published by ISC,
EMSC and seismic networks in region.
• The data for the earthquake catalog preparation can be
•
•
•
•
•
classified into three time periods, which differ in
accuracy and data sources:
I. Historical period (up to 1893);
II. Early instrumental period (1983-1970);
III. Instrumental period (1970-up to now).
The diversity of the data sources and techniques of
earthquake location, evident in those three periods, had
for its consequence differences in the level of accuracy
of all main parameters.
We came to the conclusion that it is necessary to verify
and re-interpret events in National catalog, especially
strong earthquakes with intensities >= 6.
I Historical period (before 1893)
• The earliest information on earthquakes in Serbia are dating from
1456. Earthquakes in this period have unreliable geographic
coordinates because of poor records based on which they were
located. Their seismic intensity was defined mostly based on small
number of poorly defined data, while the depth of their hypocenters
remained unknown.
• These earthquakes only represent evidence of the seismic activity in
the area and a qualitative definition of energy levels. Locations of
the epicenters are useful base for seismic zone delineation.
• Since 1879 Golubac - Moldova Noua earthquake, the collection and
systematization earthquake effects significantly increased. Those
data were the basis for the assessment of earthquake intensities,
macroseismic magnitudes and depths acording to intensity
distribution.
II Early instrumental period (18931970)
• Macroseismic data base of strong earthquakes for this period
together with instrumentally recorded data, offered a reliable basis
for the assessment of eq parameters with sufficient accuracy.
• Instrumentally recorded earthquakes from this period were
relocated using seismic models calculated for the territory of Serbia,
while their magnitudes were redefined using all available data.
Hypocenter depths were calculated and verified comparing them
with the distribution of macro seismic effects in relocation
procedure.
• For the strongest events which occurred on the territory of Serbia,
in the procedure of earthquake intensity redefinition, all available
newspaper and other reports and photos were used, including
seismic ground deformations. European Macroseismic Scale criteria
for intensity assessment were applied and vulnerability class of the
buildings in the observed time periods was also taken into account.
Preparation of the catalogue, 1893-1970
Available data sources
– Macro seismic parametric catalogue: Catalogue of earthquakes,
Part I, Part II, UNDPUNESCO Survey of the Seismicity of
the Balkan Region, 1974;
– Earthquake Catalogue for Central and Southeastern Europe 342
BC - 1990 AD, 1998 (Shebalin, Leydecker, 1998)
– Isoseismic maps
– Macro seismic earthquake catalogue in Seismological Survey of
Serbia and other studies of earthquakes
– Primary historical sources (photographs, witness descriptions in
magazines, other)
• The first catalog prepared for the
Balkans was well known
UNESCO/UNDP Project “Survey of
the Seismicity of the Balkan
Region”, edited in 1974.
• In the catalogue, earthquake
magnitudes were calculated from
intensity distribution.
• Estimation of intensities were
based on values expressed in
various macro seismic scales.
Intensity scales were not
adequately recalculated, so that
intensities of all strong
earthquakes were mostly
overrated.
For a historical and early instrumental period,
Catalogue for Central and Southeastern
Europe (1998) is relevant. Magnitudes in
this catalog are Ms and mb, determined
using macro seismic and other data, 308
of 321 events with M>=3 in Catalog are
before 1990
Magnitudes: 130 events are MS,
Macrosismique and mixed determinations
(rough estimation of MS from observed I
max and supposed depth included) with
error code :
• b = ± 0.3
• c = ± 0.5
• d = ± 0.7
• e = ± 1.0
• f = ± 1.5
• 129 events are MS, Direct measurements
with error code :
• k = ± 0.5
• l = ± 0.7
Coordinate determination: most events are
macroseismic determinations
Analysis catalog led to the conclusion that it
should be revised
Preparation of the catalogue
historical and early instrumental period (1879-1970)
• The assessment procedure of the parameters for strong
•
•
•
historical earthquakes has been applied to earthquakes
for the period 1879 - 1970.
Intensities were re-estimated using original description
of the effects: 1.003 out of 5.188 events with Io>=5
from original macro seismic catalog recorded up to 1970
are checked and processed
Epicenters were relocated using local seismotectonic
models
Based on area within isoseismic areas, earthquake
parameters - magnitude and focal depth were assessed.
VIII-IX
1893 Svilajnac earthquake
is one of the best
documented with data
collected in the field and
obtained from the local
reports
Old Isoseismal Map of the
1893 Svilajnac Earthquake
Photos show the effects on buildings and in soil in 1893 Svilajnac
earthquake
In the Monograph “Earthquakes in Serbia in 1893” geologists Jovan
Zujovic and Djordje Stanojevic described in detail efects obtained
on the field immediately after the earthquake.
“BONDRUK”-vulnerability class B
Adobe brick-vulnerability class A
Photos show typical buildings in Serbia in the end of 19. century.
Vulnerability class of most buildings in epicentral area is A and B –
fieldstone, earth brick, simple stone. Within the first isoseismal
area, it was observed that many buildings class B had 3. degree
damages and a few 4. degree. Many buildings class A had 4.
degree damages and few 5. degree.
Lokacija Lat N
Lon E
Ii
Troponje 44.160
Subotica 44.150
Medvedja 44.166
Gladna 44.083
Vel. Popo 44.116
Svilajnac 44.233
Grabovac 44.180
Sedlari 44.183
Vlaska 44.000
Lapovo 44.166
Bobova 44.233
Savac
43.850
Orasje
44.366
Vel. Plana44.500
Djurinac 44.233
Zabari
44.366
Jagodina 44.000
Kupinovac44.200
Salakovac 44.566
M. Crnice 44.550
Dvoriste 44.100
21.270
21.340
21.350
21.300
21.350
21.200
21.210
21.290
21.350
21.100
21.250
21.366
21.083
21.050
21.350
21.166
21.233
21.316
21.283
21.283
21.533
8
8
8
8
8
8
8
8
7
7
7
7
7
7
7
7
7
7
7
7
7
Based on classification in EMS scale intensity 8-9
was assessed in epicentral area. Following the
same procedure, intensities 7, 6, 5 were assigned.
Magnitude assessment is based on:
Checking M from available catalogs
Considering liquefaction phenomena (5.7-5.9)
Using Musson equation for I=3, I=4 area
Checking our equation for I=5 area.
Isoseismal Map of the 1893 Svilajnac Earthquake
According to the area affected with
particular intensity and using intensity
attenuation relation,
Ii=1.3786 M - 3.243 D + 3.4019
magnitude 5.8 and 8 km depth 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
now)
• As the number of seismological station increased and
was accompanied by a constant improvement of the
quality of recorded data
• Large high-quality data base was accumulated and as a
consequence made it possible to work on various
seismological research, such as defining regional seismic
and seismotectonic models.
• Extensive studies have been conducted in recent years
to revise earthquake catalog by making use of numerous
internal catalogs (combination of parametric catalogs
and authentic earthquake data and their effects), as well
as the bulletin data published by ISC, EMSC and seismic
networks in region.
• 1970-1990: 457 events M>=3 checked and/or processed
Number of eq`s increased ~50% comparing to
Shebalins catalog.
All available data are processed in program “Potres” using most
reliable data
Local and regional velocity models are used and tested to fit the
best solution and minimum correction.
Example is numerical processing of 1927 Rudnik earthquake,
M=5.9, Io=8 which is recorded at 63 stations 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 M>=3.5
~ about 320
earthquakes Io>=6
with epicenters in the
territory of Serbia are
processed for BSHAP
I
Earthquake Catalogue M>=3.0
>880 earthquakes Io>=5 in
macroseismic catalog are
processed for BSHAP II,
~600 events in total are
added to Catalog
~4.560 events with Io=3-4
in macroseismic catalog
to be checked, many of
them having usefull
informations which
enables assessment of
magnitude and focal
depth
Unification of the magnitude scales
• For a historical and early instrumental period magnitudes Ms and
•
•
•
•
•
•
Mb are used
For strongest instrumentally recorded earthquakes, magnitude Mlh
is often determined, which corresponds to Mw magnitude for
magnitude range 5=<M=<8.
For the period between 1963 and 2005, the catalogue consists of
the earthquakes re-assessed acording to ISC data in which Mb and
Ms and Mlh for the strong earthquakes (from Wiechert and Mainka
seismograms) are published.
Since 2005, magnitude ML have been determined for the
earthquakes in Serbia.
Using 180 earthquakes with Ms/mb pairs in ISC Catalog, the
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