Seismotectonics of NW Iran (Region of Azerbaijan) based on Destructive Earthquakes and Activity of Faults
Dr. Tohid Malekzadeh Dilmaghani[1]
Abstarct
Historical and istrumental earthquakes as well as geological evidence show that Azerbaijan (NW IRAN) is the most active seismic region in Asia. Many destructive earthquakes have already occured in Tabriz, Salmas, Ardabil and other major cities. Some destructive earthquakes have recently occured in the region such as the earthquake in Salmas (1930) with M= 7.2 , in Chaldran (1976) with M= 5.5 , in Rudbar- Zanjan and Tarem (1990) with M= 7.0 and in Ardabil (1996) with M= 5.5. The evidence shows that this region has a very destructive position. The epicenters of local earthquakes are in agreement with the NW-SE trending major faults. Through the present paper, we will first show the major faults, hitorical earthquakes and major instrumental earthquakes in recent decades in Azerbaijan. The distribution of the earthquakes in the East, West and centeral parts of Azerbaijan are cosistent with the related major faults. The Study of the distribution of earthquakes in the East, West and centeral parts of Azerbaijan show that there exist seismic quiescence in the centeral parts around Tabriz which caused many destructive earthquakes in the past. According to historical earthquakes around Tabriz and the existance of energy gap around this region, the occurrence of a major earthquake in Tabriz and centeral Azerbaijan in near future and in the West and East of Azerbaijan in far future is expected.
Keywords: Seism tectonics, Destructive Earthquakes, NW Iran, Azerbaijan
İntrouduction
Azerbaijan which is located in 36-50 East longitudes and 36-44 North latitudes is one of the seismic active regions in Asia . This region has experienced many destructive earthquakes in the past centuries. However there were not enough data to evaluate seismic activity in Northwest Iran. The destructive Ardabil earthquake (March 1996) and Rudbar-Zenjan earthquake ( June 1990) need to install a permanent seismological network in Azerbaijan especially in centeral Azerbaijan (Gheitanchi et al , 2004). Therefore, in 1995 the Institue of Geophysics of Tehran university deployed a telemetric seismic network in the centeral part of Azerbaijan to monitor the seismic activity. But it is not enough to monitor all of the Azrbaijan earthquakes.
In this paper, we will first present a detailed and reliable faults of northwest Iran and review the historical detructive earthquakes that have occurerd in the region . Then we will try to find a relation between historical and instrumental earthquakes with major and minor faults in Azerbaijan.
1. Major and Minor Fault in Azerbaijan
Azerbaijan which is located between Caspian see in the East and Anatoliyan in the West and caucasus in the North and Zagros mountains in the South have been compresed between Turan and Arabiyan plates and the Caspian microplate. The Compression of these plates cause faults and cracks in Azerbaijan. Many of these faults, e.g. The North Tebriz Fault , Urmiya fault and Astara Fault are among the major faults of Azerbaijan. North Salmas fault, Van fault and North Tebriz Fault are minor faults of Azerbaijan. Table 1 show the main major and minor faults in Azerbaijan.
Majority of these faults have strike – slip position of fult which shown in table1.
Many people have studied historical earthquakes of Azerbaijan. Ambraseys (1974 & 1982) and Berberiyan (1976) and Malekzade (1998) . In this Paper, we will try to list major earthquakes which occured in Azerbaijan during last 2000 years.
200 y B.C : Maku
461 Malazgirt : destructive earthquake
634 Tabriz :Destructive earthquake in Tebriz with M= 6.0
694 Tabriz : earthquake in Tebriz
735 Zangezor: Destructive earthquake in south Aras revier
746 Tabriz: No detail
834 Tabriz : No detail
849 Tabriz : No detail
851 Iravan :No detail
858 Tabriz: Destructive earthquake in Tebriz with M= 6.0 , epicente coordinate 38.08 N ,46.26 E
858 Aras River : epicente coordinate 39'9 N ve 44'20 E
863 Dovin :Destructive earthquake in Dovin with M= 5.2
868 Tabriz : No detail
869 Aras River : epicente coordinate 39' 95 N and 44'20 E
893 ( 28 December) Dovin : Destructive earthquake in Dovin
893 - 4 Ardabil: estructive earthquake in Erdebil with M= 6.0
906 Zangezor : Destructive earthquake in Zengezor , range of feeling 180 km.
949 Tabriz : No detail .
1020 Tabriz: : No detail.
1041 Tabriz : Destructive earthquake in Tebriz with 5000 killed.
1042 (4 October) Tabriz : Destructive earthquake in Tabriz with M=7.6. epicentere coordinant 38.1N and 46.3 E ( Ambersiyes, 1982) .
1135 ( 25 June) Sardasht : Destructive earthquake in Sadasht with M=6.1 .
1135 ( 11 January ) Sardasht: Destructive earthquake in Sardasht with M=6.4:. range of feeling 300 km and epicentere coordinant 36.1 N and 45.9 E . (Ambersiyes 1982 )
1139 Ganja : Destructive earthquake in Ganja .( Guliyov , 1359 )
1273 ( 18 Junery ) Tabriz : Destructive earthquake in Tebriz with 250 killed. Feeling aftershok till 4 months later.
1275 Azerbaijan : Earthquake in Azerbaijan.
1304 Sarab , Garadagh : Destructive earthquake in Sarab with M=6.7
1305 ( 16 April ) : Azerbaijan : Earthquake in Azerbaijan.
1308 Zangezor : No detail ( Berberiyan, 1977)
1314 Tabriz : Earthquake in Tabriz.
1319: Maku :Destructive earthquake in Sarab with M=5.3 with 53 killed.
1320 Kars : Destructive earthquake in Sarab with M=5.9, range of feeling 100 km
1345 Malazgirt : eartquake in Malazgirt.
1406 ( 29 Novamber ) : Zengezor : No detail. (Ambarseyes 1982) .
1436 Azerbaijan : No detail.
1441 M Tabriz : earthquake in Tabriz.
1459 M Tebriz : earthquake in Tabriz.
1550 Tabriz : Earthquake in Tabriz with 36.8 N and 46 E episenter coordinate
1567 Garadag : Destructive earthquake in Karadag. With epicenter 39 N and 47.2 E
1572 Tebriz : No detail.
1593 Serab : Destructive earthquake in Sarab with M=6.1.
1621 ( 21 June ) Miyana : earthquake in Miyana with intensity I= V ( Ambersyes , 1982 ).
1622 Maku : earthquake in Maku ( Ambersyes , 1982 ).
1633 Tabriz : earthquake in Tabriz.
1640 Tabriz : earthquake in Tabriz.
1641 (5 Feburey) Tabriz : Destructive earthquake in Tabriz with M=6.8. Feeling range 200 km, people killed: 10000.
1648 ( 13 March ) Van : Destructive earthquake in Van with M=6.5. Feeling range 300 km, people killed 4000 ( Ambersyes , 1982 ).
1649 Tabriz : earthquake in Tabriz ( Berberyan , 1976).
1650 Tabriz :. earthquake in Tabriz.
1657 Tabriz : earthquake in Tabriz.
1659 Kara kilise : No detail
1664 Tabriz : Destructive earthquake in Tebriz with M=6.5 , with epicenter coordinante 38.1 N and 46.3 E.
1668 ( 7 January ) Tabriz : earthquake in Tabriz with M= 6.5
1669 ( 4 January ) Iravan : Destructive earthquake in Iravan with M=6.2. Feeling range 200 km, people killed 1228. with epicenter coordinante 40.40 N and, 44.50 E.
1696 ( 16 June ) Chaldran, Maku : Destructive earthquake in Iravan with M=6.2. Feeling range 200 km , people killed 2000, with epicenter coordinante.39.1 N and 43.9 E
1715 ( 8 March ) South of Van : Destructive earthquake in South of Van with M=6.6. Feeling range of 320 km, with no killed people in Van but some killed in the south of Van
1716 ( 23 January ) North of Aras River : Destructive earthquake in North of Aras River and South of Iravan with M=6.6. with epicentere coordinate 40.2 N and 44.5 E ( Ambersyes ,1982 ).
1717 ( 12 March ) Garadagh-Tabriz : Destructive earthquake in Karadag- Tabriz M = 5.9.
1721 ( 26 April) Tabriz – Bostanava : Destructive earthquake in Tabriz – Bostanava with M=7.0 . Feeling range of 700 km , 60000 killed.
1727 ( 18 October ) Tabriz : Destructive earthquake in Tabriz, 17.000 killed.
1755 Tabriz : No detail.
1774 Tabriz : earthquake in Tabriz.
1780 Tabriz : Destructive earthquake in Tabriz with M=7.7 , feeling range o0f 300 km and 400 villages damaged.
1783 ( 13 Junery ) : Earthquake in Agri. No detail
1786 (18 Novamber) Marand : Destructive earthquake in Marand with M=6.3 and 4.000 killed.
1787 Tabriz : earthquake in Tabriz (Berberyan , 1976 )
1791 Tabriz : earthquake in Tabriz (Berberyan , 1976 )
1803 Tabriz : earthquake in Tabriz.
1808 ( 11 Junery ) Tasuj : Destructive earthquake in Tasuj with M=6.0 and feeling range of 120 km.
1808 ( Junery ) Khoy : earthquake in Khoy.
1812 Julfa : earthquake in Julfa.
1812 ( 14 June ) Tabriz : earthquake in Tabriz.
1819 ( 29 Junery ) Tabriz –Tasuj : earthquake in Tabriz –Tasuj.
1820 ( January) Tabriz :earthquake in Tabriz:.
1823 (December) Tabriz : earthquake in Tabriz.
1828 ( 14-16 Agut ) Garabagh : earthquake in karabagh.
1829 ( 29 April ) Khoy : erathquake in Khoy.
1831 Tabriz : earthquake in Tabriz.
1832 ( 8 December) Astara : earthquake in Astara.
1837 ( 7 June ) Salmas : Earthquake in Salmas.
1840 ( 22 January ) Astara : Erathquake in Astrada.
1840 ( 2 January ) Maku- Aghridagh :Destructive earthquake in Maku- Aghridagh with M=7.2 and feeling range of 400 km ,aftreshok until 8 months later.
1843 ( 18 April ) Khoy : Destructive earthquake in Khoy with M=5.9 and feeling range of 19 km, 1000 people killed.
1843 till 1857 Tabriz :earthqakue in Tabriz .
1846 ( 22 January ) Ardabil: Earthquake in Ardabil.
1857 Tasuj: earthquake in Tasuj, 3 people killed.
1859 Shamakhi: Earthquake in Shamakhi , city destroyed
1862 ( 30 December ) Ardabil - Hir : destrucive earthquake in Hir. 500 people killed.
1870 ( 26 January) Tabriz : earthqakue in Tabriz
1872 Azerbaijan :earthquake in Ganja and Iravan.
1874 ( 28 June ) Tabriz : earthquake in Tabriz –Miyana.
1879 ( 22 March ) Miyana: destrucive earthquake in Miyana, 1000 people killed.
1880 ( 4 Junery) Gerus : earthquake in Gerus .
1883 ( 3 June) Tabriz : earthquake in Tabriz.
1894 ( 9 June ) Tabriz : earthquake in Tabriz.
1895 ( 18 December ) Khalkhal : destructive earthquake in Khalkhal.
1896 ( 4 Junery ) Khalkhal : destructive earthquake in Khalkhal.
1896 ( 5 Junery) Khoy : earthquake in Khoy.
1900 ( 24 February ) South of Khoy : earthquake in Khoy , Many houses damaged.
1902 M ( 13 February ) Shamakhi :earthquake with M= 6.0 in Shamakhi.
1924 M (19 Feburay) Garadagh :earthquake with M= 6.0 in Karadagh.
1930 M ( 6 April ) Salmas :earthquake with M= 5.5 in Salmas.
1930 M ( 7 April ) Salmas: earthquake with M= 7.2 in Salmas
1931 ( 27 April) Zangezor: earthquake with M= 6.2 in Zangezor.
1965 ( 10 February ) Bostanava- Tabriz : earthquake with M= 5.1 in Bostanava
1966 ( 20 March ) Maku : earthquake with M= 6.0 in Maku
1968 M ( 29 April) Maku : earthquake with M= 5.3 in Maku.
1970 M ( 14 March ) Khoy : earthquake with M= 5.3 in Khoy
1970 M ( 4 October ) Pasva : earthquake with M= 5.5 in Pasva.
1976 M ( 24 November ) Chaldran : earthquake with M= 5.5 in Chaldran.
1990 M ( June) Tarem : earthquake with M= 7.0 in Tarem, Zanjan, Rasht and Manjil , 40000 killed.
1996 M ( 28 February) Ardabil : earthquake with M= 5.5 in Ardabil- Sareyin ,1000 killed.
Discussion and Conclusion
Historical and instrumental earthquake studies have shown that the region of Azerbaijan and especially its capital, Tabriz, has a very active crust and has been damaged several times.
Western part of Azerbaijan except Urmia has a very activ position. Salmas, Khoy, Ushnu and Sardasht have been dameged and destroyed during last 2000 years. For example salmas was desrtoyed in 1930 by an earthquake with the magnitude of M=7.2. The Centeral part of Azerbaijan had experienced destructive earthquakes that some of them damaged Tabriz and its neighbourhood completely. But within last 200 years, we have not experienced any destructive earthquake in Tabriz, so this region has a high risk for damaging. Eastern part of Azerbaijan had destructive earthquakes in historical times. There happened an earthquake (1990) in Tarum and Zenjan and another one (1995) in Ardabil. These earthquakes show that this region has an active position, either in past or in present, so we don't expect any big earthquake in this region.
Acknowledgments
The authors would like to thank University of Ankara , geophysic branche where this paper was prepared and Prof. Dr. Akashe who was my supervisor in doing my MS Thesis
Table 1. Main major and Minor faults in the region of Azerbaijan
|
No |
Fault Name |
Max Fault Lenght ( km) |
Fault Lenght (km) |
Average Magnitude ( expected) |
Max Intensity ( expected) |
|
1 |
N. Tabriz |
180 |
100 |
7,4 |
9,7 |
|
2 |
Pasva |
180 |
80 |
7,3 |
9,6 |
|
3 |
Salmas |
40 |
38 |
6,9 |
9,1 |
|
4 |
Tasuj |
57 |
53 |
7,1 |
9,3 |
|
5 |
N.Mişov |
45 |
42 |
7,0 |
9,2 |
|
6 |
S.Mişov |
23 |
23 |
6,7 |
8,8 |
|
7 |
N. Salmas |
17 |
17 |
6,5 |
8,5 |
|
8 |
Sharafkhana |
50 |
44 |
7,0 |
9,2 |
|
9 |
Sofyan |
53 |
48 |
7,1 |
9,3 |
|
10 |
Ushnaviya |
20 |
20 |
6,6 |
8,7 |
|
11 |
Urmiya |
75 |
63 |
7,2 |
9,4 |
|
12 |
Mughan |
130 |
100 |
7.4 |
9.7 |
|
13 |
Zanjan |
120 |
100 |
7.4 |
9.7 |
|
14 |
Ipak |
120 |
100 |
7.4 |
9.7 |
|
15 |
Harzavil |
180 |
80 |
7,3 |
9,6 |
Table 2. Destructive Earthquakes in the region of Azerbaijan
|
No |
Fault Name |
Region |
Earthquake Date |
|
1 |
North Tabriz |
Tabriz |
634,694,746,834,849,858,868,949,1020,1041,1042,1273, 1314,1441,1459,1550,1572,1633,1640,1641,1649,1650, 1657,1664,1668,1717,1721,1727,1755,1774,1780,1781,1791, 1803,1812,1819,1820,1823,1831,1843,1870,1874,1883,1894
|
|
2 |
Aghri |
Maku |
200B.C ,1319,1622,1659,1696,1783,1840,1966,1966,1968,1976 |
|
3 |
Zangazor |
Zangazor |
735,906,1308,1406,1931,1965 |
|
4 |
Zangazor |
Iravan |
851,858,869,1669,1716,1872 |
|
5 |
Aghri |
Dovin |
863,893 |
|
6 |
Neor |
Ardabil |
893,894,1846,1862,1996 |
|
7 |
Pasva |
Sardasht |
1135,1970 |
|
8 |
Ganja |
Ganja |
1139,1872 |
|
9 |
N.Tabriz |
Sarab |
1304,1567,1593,1717,1924 |
|
10 |
N.Tabriz |
Miyana |
1621,1879 |
|
11 |
Van |
Van |
1648,1715 |
|
12 |
Mishov |
Marand |
1780 |
|
13 |
Mishov |
Tasuj |
1808,1819,1857 |
|
14 |
Var |
Khoy |
1808,1829,1843,1896,1900,1970 |
|
15 |
Zangazor |
Julfa |
1812 |
|
16 |
Garabagh |
Garabagh |
1824 |
|
17 |
Astara |
Astara |
1832,1840 |
|
18 |
Salmas, Derik |
Salmas |
1837,1930 |
|
19 |
Shamakhi |
Shamakhi |
1859,1902 |
|
20 |
Harzavil |
Tarem |
1990 |
|
21 |
Khakhal |
Khalkhal |
1895,1896 |
figure 1. Seismotectonic map of Azerbaijan (Gheitanchi et al 2004)
References:
Ambersayes, N.N. and Melvil,C.P., 1982, A History of Persian Earthquakes , Cambridge University Press, 219p.
Barbarian. M. 1976, Salmas earthquake, Iran Gs Report No 39
Barbarian. M. 1976 Contribution to the Seismotectonies of Iran (part IV), Iran Gs Report No 40
Barbarian. M. Tchalenco. J.S.1976 Field study and documentation of The 1930 Salmas earthquake, Iran Gs no 49 P 271- 342
Barbarian. M. 1976 Macro seismic epicenters of destructive and damaging earthquakes in Iran (1900-1976). Iran Gs No 39
Gheitanchi, M.r., Mirzaei.N. Bayramnajad.A., Pormohammad.B., Farazmand.A., 2004, Pattern of Seismicity in Northwest Iran, Revealed from Local Seismic Network, Geoscınenses, vol.11 no.49-50
Malekzadeh, T., 1998, Azerbaijan Earthquakes. MS Thesis. Tehran , Islamic Azad university, North Tehran branch