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TABLE I. Cont. FAgLT N~HE FT FL EQ. DATE Ms ~ ~4I EFL MO. SD REF" Nr North Tabrlz R 0200 0858.00.00 VII 9,16,18 1042.11.0q VIII 19,35 1304.11.07 VII 13~5.00.00 1459.00.00 VII 1550.00.00 VII 16~1.04.05 VIII 1650.00.00 1657.00,00 1664.00.00 1721.04.26 VIII 1727.11.18 Vlll 1779.12.27 VIII Nt North Tehran R 1856.10.04 1965.02.10 0090 1665.06.00 5.1 VII 9,10,11 1802.00.00 18,19 1811.06.20 1830.05.09 1830.10.02 1955,11.24 4.0 VI 1970.10.03 4,1V Nz Nozad R 0060 1493.01.10 VIII >10 1,2,8, 9,27 P Pasveh 0060 1970.10.25 5.5 VII Q Oarnaveh R 0050 1970.07.306.7 5.7 VIII 0120s 6,16,36 Qo Ootur R 0040 1715.03.08 VII 28 1969.O5.14 4.5 VI Ou Ouchan SS 0050 1871-1872 2,7 1893.11.17 R RafsanJan R 0110 1923.09.226.7 VIII 4,9 S Sabzevar R 0070 1052.06.02 VIII 2,18,19 Sa ~almas SS 1930.05.067.4 X >30 2,37,38 Sg Sansavar R 0070 1863.12.30 11,16 186q.01.02 VIII 1896.01.02 VIII 1969.03.10 V Sh Shavar N 0080 1890.07.11 VIII 11,16 Sk Siahkuh R 0140 1977.05.25 5.4 VI Sy Shekaryazl R 0015 1930.05.086.2 VII 2 T Tabas R 1939.06.10 5.5 VII 2 1974.06.17 197q.06.24 4.8 VI 1978.09.167.7 6.5 X 085 1300F 025 O~q0p 017 Ta Takal Kuh R 0100 1974.03.07 5.2 VI 16 T1 Talesh R 0120 1913.04,16 5.2 9,16 1978.11.04 6.0 VII Ts Tasuj R 0030 1857,10.27 11 Tt Torbat Jam N 0080 1918.O3.245.8 VII 1,2 Tu Torud R 0120 1953.02.126.4 VIII 8,9,16 V Vondik R 0055 1976.11.O76.2 5.6 VII Y Yazd R 0070 1975.11.15 4.2 V 1976.O2.15 ~.4 V 1978.02.16 4.5 V 44 1 Ambraseys and Melville 1977 6 Tehalenko et al. 1974 2 Berberlan 1979a 7 Tchalenko 1975a 3 Haghlpour and Amidl 1980 8 Berberlan 1976b 4 Berberlan 1976e 9 Berberian 1976a 5 Berberian 1977b 10 Berberian 19768
11Ambraseys 1974 24 A=braseys 1963 12 Ambraseys and Tchalenko 1969 25 Berberian 1976d 13 Tchalenko and Berbertan 1975 26 Ambraseys et al. 1969 14 Hanks and Wyss 1972 27 Ambraseys 1975 15 North 1973 28 Tehalenko 1977 16 Berberlan 1981b 29 Tok~oz and Arpat 1977 17 Tehalenko et al. 1973 30 Toksoz et al. 1977, 1978 18 Melville 1978 (used only for 31Berbertan et al 1979a correcting the European dates 32 Berberian 1976e of few historical earthquakes) 33 Tehalenko and Braud 1974 19 Nabavl 1972 34 Melville 1980 20 Tehalenko 1974 35 Berberlan and Arshadt 1976 21Ambraseys et al. 1979 36 Ambraseys et al. 1971 22 Heuckroth and Karlm 1970 37 Tchalenko and Berbertan 1974 23 Polrler and Taher 1980 38 Berberian and Tchalenko 1976c Abbreviations used in the Table: EFL=Earthquake fault length in km, EO.=Earthquake, FL=Fault length in km, FT=Fault type (R:reverse, SS:strike-slip), Mb=Body-wave magnitude, MMI=Modified Mercalli Intensity, MO.=Seismic m~ment :x102&dlme-cm(values calculated from: f=field data, P=P-wave spectrum, p=long period P-waveforms, S=S-wave spectrum, s=Surface wave determination), Ms=Surface-wave magnitude, R=Reverse fault, SD=Stress drop in bars, S~=Strlke-slip fault, =Possible active fault related to the mentioned earthquake. First colt~nn letters indicate official fault names (given in the second column) shown in Fig. Haftgel and HendlJan highs [see Morris 1977] seem to be inactive today (Fig. 12). The Zagros earthquakes have shown that, with the information presently available, it is not possible to use selsmicity to establish smaller selsmotectonic units. Neither the mountain/depression division, nor the large scale fault-flexure zones or strongly folded arcs, nor the surface faults (except major boundary faults cutting basement and the sedimentary cover) can be correlated easily with the earthquake locations. It therefore seems that the Zagros belt should neither be divided into several selsmotectonic zones as suggested by Nowroozl [1976], nor that expected maxlmom intensities for future earthquakes should be assigned to different zones. The large magnitude basement earthquakes in the Zagros showed that earthquakes may occur anywhere. Since no correlation can be established between the selsmlclty (reactivation of basement faults) and the tectonic features at the surface, it should be assumed at present that an event has the same probabillty of occurrence anywhere in the Zagros. That is to say, the seismic risk level will be the same everywhere along the belt until we recognize the exact position of the longitudinal reverse active faults in the basement. Compllatlon of accurate macroselsmlc data of the belt would show the trend and the location of the buried basement reverse faults in the Zagros. Unfortunately the seismic history of the Zagros (especially the historical earthquakes) is not doc~ented well enough to be used for detecting all seismic trends in the belt. The available seismic data together with preliminary conclusions are presented in Figures 5 and 7 (see also Table II). The data seems to suggest a few distinct seismic trends which are given below. Some of the longitudinal seismic trends apparently coincide with sedimentary facies changes in the Zagros sedimentary basin. It is difficult to understand this because the detachment and southward displacement of the sedimentary cover must have severed the facies boundaries from underlying basement faults. a. Assaluyeh Trend: This trend contained 10 damaging and destructive earthquakes (Figs. 5 and 7; Table II). There are several indications that the Assaluyeh seismic trend (buried seismic reverse fault) coincides with sedimentary facies changes. The Assaluyeh seismic trend is near the southwestern boundary between the Jurassic shallow marine carbonates (Surmeh Formation in the NE) and the lagoonal-reefal carbonates (Sargelu Formation in the ~d) [Mina et al. 1967]; it lies along the change between the Eocene nerltlc to baslnal marls of the Pabdeh Formation in the south and the transitional shallow marine carbontes and nerttlc to bastnal marls (Jahrom-Pabdeh Formation) In the north [James and Wynd 1965, Mlna et al. 1967]; it ls approximately the southern limit of the early to Mlddle Miocene Mtshan sea with shale and marl depositions [Btzon et al. 1972, Rtcou 1974]; lies parallel to the maln Tertiary foredeep [Kamen Kaye 1970]; and finally it corresponds to the present dlvldlng line between the Zagros foldthrust belt in the NE and the Arabian platform in the ~W, and also corresponds to the boundary between the mountain front and the foothills of the Zagros belt. ACTIVE FAULTING AND TECTONICS OF IRAN 45
Page 1 and 2: Reprinted from Zagros ¯ Hindu Kush
Page 3 and 4: Inset left: Dlstrlbutlon ofeplcentr
Page 5 and 6: Araxlan-Azarbaijan zone of Caledoni
Page 7 and 8: GULF OF OMAN Fig. ~. Fault Hap of I
Page 9 and 10: 2. Segments of the High Zagros deep
Page 11: TABLE I. Cont. F~_U~LT # ~L~ME FT F
Page 15 and 16: ~ U.PRECAMBRIAN HORMOZ SALT TECTONI
Page 17 and 18: TABLE II - Seismic trends (buried h
Page 19 and 20: Indicating that the reglon ls asets
Page 21 and 22: |Taba s J J Khaf Sabzevar Kuh Banan
Page 23 and 24: CASPIAN SEA 0 200 km 1979 38’ AFG
Page 25 and 26: CASPIAN SEA GULF OF OMAN Fig. 12. E
Page 27 and 28: Dominance of 170 My or 210 My of An
Page 29 and 30: 1977, Sykes 1978] and the deformati
Page 31 and 32: the fact that the cruat consists of
Page 33 and 34: western Alpine system, In: Biju-Duv
Page 35 and 36: Nabavi, M.S., Selsmicity o£ Iran,
Page 37: Wowroo zi, Seismological and geolog

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