national report of country earthquake researches

Description

Shahvar Fault is situated to North Sharoud, a border among Alborz Mount. and North Shahroud Desert – Bastam. To west of Negarman, Paleozoic layers are with northward dip and wall of erosional fault is driven on the plain. Reverse fault of Shahkouh is a fault with a length of over 115 km and with a trend of E-SW and a rake towards NW which passes through North and North West of Shahroud City. Following earthquakes are occurred young faults of Shahkouh: -             Earthquake in June, 11, 1890, Tash-Shakouh with magnitude of Ms=7.2, I o= ІΧ -             Earthquake in Oct., 39, 1985, with magnitude of Mb=6.0, Ms=6.0 3-1-1-12- North Alborz Reverse Fault Reverse Fault to North Alborz is a fault with bending trend with an approximate trend of W-E and dip towards South and a length of 300 km. wall of Northern Alborz Fault is on the ground surface obviously and also on aerial inscriptions. North Alborz Fault is a seismic fault and likely with a magnitude of Ms=6.8 and intensity of I o=VIII+ due to movement of this fault (Berberian and Ghoreishi, 1367). 3-1-1-13- Reverse Fault to North Tabriz Reverse Fault to North Tabriz which passes through Tabriz City and a fault with a trend of NW and SE (N115E) and its much dip is NE which crosses young sediments pertaining to Quaternary and it has a seismic history. Huge earthquakes are occurred related to fault movement to North Tabriz (Ambraseys and Melville, 1982; Berberian, 1981 & 1983). -             Earthquake, 58 AD, with magnitude of Ms=7.6, I o= Χ -             Earthquake, Nov. 4, 1042, with magnitude of Ms=7.6, I o= Χ -             Earthquake, Apr. 26, 1721, with magnitude of Ms=7.7, I o= Χ -             Earthquake, Jan.,7-8, with magnitude of Ms=7.7, I o= Χ -             Earthquake, Feb. 10, 1965, with magnitude of Ms=5.1, I o= VI-VII   3-1-1-14- North Tehran Thrust North Tehran Thrust has a length of 90 km that a part of that is a border between Miankuh and To North Tehran City. Mechanism of North Tehran Thrust is a thrust and it results in Karaj Fm. Thrust in most places (with an age of Eocene) and heterogeneous Alluviums to North Tehran and Pediment zone to north Central Iran to North Tehran. Height difference is between Tehran City and nearest crest to that in a distance of less than 10 km( Tochal Crest with a height over 3933m) is as a most distinct characteristics for zone topography which have been formed due to thrust movement in Tehran thrust (Tchalenco et al., 1974, Berberian et al., 1364): -             Earthquake, Nov. 4, 1042, with a magnitude of Ms=7.7, I o= Χ -             Earthquake, Feb. 23, 958, with a magnitude of Ms=7.7, I o= Χ -             Earthquake, May, 1177, a zone between Shar-e-rey and Qazvin with estimated magnitude of Ms=7.2, I o= IΧ -             Earthquake, Oct., 3, 1970, in Rudbar Ghasran with a magnitude of Ms=4.1, by means of ISC and USGS in 25 and 23 km from North Tehran Thrust is centered and it may be occurred due to movement in this fault. -             Earthquake, Oct., 26, 1989, Tojan Kelayeh to North East Tehran   3-1-1-15- North Rey Fault  North Rey Fault is a as erosional wall by side of southern side in Rey Behesht Zahra Highway around Azim Abad Village. This fault is with a height of 2 meters with a trend of E-W and a length approximately 17 km from North and North West of Shahr-e-rey. To North and North West of Shahr-e-rey, there is an anomaly in trend of Groundwater based on measurement in water table trend (Piezometric) in groundwater (Knill and Jones, 1968), power and water ministry, 1970, Tchalenco et al., 1947, which are correlated on the trend of North Rey Fault and it is indicative of importance for this operation in this fault through groundwater displacement. 3-1-1-16- North Qazvin Reverse Fault North Qazvin Fault is a fault with a trend of E-W for a length over 60 km which passes in a little distance of Qazvin City to Northern Parts. Young Thrust in Qazvin is a seismic fault but because of little data, history of its seismicity is not completely characterized. It may be a s a result of an earthquake from 10, Dec., 119 in Qazvin with a magnitude of Ms=6.5 and Io=VII due to fault movement to North Qazvin. 3-1-1-17- Qezel Ozan (Manjil Thrust) Qezel Ozan thrust is a fault with bending trend of NW-SE which is situated in Northern part of Ghezel Ozan and between Mountain and Qezel Ozan Valley and it passes under Manjil Sefisrud. In west of Sefidrud Dam, Karaj Eocene Fm. is located on Neogene Marls which are in shape of nappe and it is seen obviously (Berberian and Ghoreishi, 1363). Big seismic focus in the earthquake, 2rd Aug., 1968, Sefidrud Dam (Manjil) and 22 Jun., 1983, in Tarom and near this fault with Qezel Ozan and it can be representative of seismicity and this active fault. 3-1-1-18- Kashafrud Reverse Fault Kashafrud Reverse Fault (Berberian, 1361, Berebrian and Ghoreishi, 1368, Berberian, 1981) or a bending trend of NW-SE with a length of 120 km. presence of triangular facet in this trend, shear in alluvial young sediments, presence of abundant springs (for instances in Cheshmeh Gillas and creation of fault scarp in all of its length and it is indicative of Kashafrud Fault (Berberian and Ghoreishi, 1368). Kashafrud Fault is a fault and destroyer in date of 30/7/1673 (Io=VIII + and Ms=6.6) and also April of 1678 Mashhad in order to reactivation of this fault. Locating earthquake center is near to Kashafrud Fault in date of 28/9/1988 may be representative of this fault in 20th. 3-1-1-19- Kuhbanan Fault Kuhbanan seismic Fault is a fault with general trend of NW-SE and a length with 300 km which passes from north Kerman and East Zarand.  Young Kuhbanan Fault is an active fault but its presence in centers from villages and little population in its path results in some little data in this fault and minimum destroyer earthquake which has been caused due to activity of Kuhabanan Fault (Berberian et al., 1984). -             Earthquake 11/1854, Hourijan (Io=VII+, Ms=5.8) -             Earthquake 17/1/1864, Chatrud (Io=VIII, Ms=6) -             Earthquake 4/8/1871, Chatrud (Io=VIII) -             Earthquake 27/5/1897, Chatrud (Io=VII, Ms=5.7) -             Earthquake 13/2/1937, in Tanglal (Io=VII, Ms=4.7) -             Earthquake 17/9/1977, Deh Zuieh (Io=VI, Ms=5.6) -             Earthquake 10/11/1977, Deh Zuieh (Io=VI, Ms=4.8) -             Earthquake 19/12/1977, in Tangal (Io=VII+, Mb=5.8, Ms=5.7) 3-1-1-20- Great Kavir Fault (Doruneh) Great Kavir Fault (Doruneh) is one of fundamental structures in Iran which is stretched from Iran Eastern borders to central part of Kavir Plain Central Parts. In spite of this fundamental fault, young and long sediments embed Quaternary Sediments but there are no much seismic data. Big earthquake data indicates that Kashmar (Tertiary) has been in trend of great Kavir Fault (Doruneh) even though there are some completely characterized evidences representative of two earthquakes with activity in this fundamental structures. 3-1-1-21- Kahrizak Fault Kahrizak Fault is a high wall (1to10 m) with a trend of E-W and with a length of over 10 km from south Shahr-e-rey. Fault has a mechanism of thrust with a northward rake. 3-1-1-22- Gharun Fault  Gharun Fault which is forming a branch from young Zagros Fault, with a trend of W-SE in distance of about 15 km from W-SW of Nahavand Fault and it is parallel to that. Trace of Gharun Fault is as a topographical wall with a height of several meters obviously and it is same part which is reactivated during earthquake event of 16 Aug. 1958, Firouz Abad ( North West Nahavand) ( Berneriam and Ghoreishi, 1363). 3-1-1-23- Garmsar Fault        Garmsar Fault is a fault with general trend and bended with trend of NE-SW and its length is over 100 km in North East part of Garmsar, this fault is a border between Hezar Dareh alluvial Fm. and Desert alluviums. Following earthquake may results in reactivation of Garmsar Fault. -             Bahar Earthquake, 743 AD in Khazar Darvazeh ( Sardare, Ivanakey and Garmsar Defile) with estimated magnitude of Ms=7.2 and Io=VIII+ -             Earthquake, May, 11, 1945, Bonkuh Garmsar with magnitude of Mb=4.7 -             Aftershock in Garmsar Bonkuh Earthquake (19 Jun. and 28 Oct., 25 in Garmsar with a magnitude of Mb=4.6 and Io=V. 3-1-1-24- Gouk reverse Fault Gouk reverse Fault is a fault with a trend of NNW-SSE and a length over 200 km and it passes more or less from East Kerman. Active fault system of Gouk results in perch compressional depression which is narrow and long and it is solved in its trend ( Berberian et al., 1984). Activity of active and seismic Gouk Fault results in many earthquakes such as following cases: -             Earthquake 1877, Siraj (Ms=5.6 and Io=VII) -             Earthquake 27/10/1909, Joushan (Ms=5.6 and Io=VII) -             After shock 6/11/1909, Joushan (Ms=5.6 and Io=VII) -             Earthquake 29/4/1911, Feiz Abad(Ms=6.4, Mb=5.6 and Io=VII) -             Earthquake 5/7/1948, Gouk(Ms=6.0, Mb=5.9 and Io=VII) -             Earthquake 2/9/1969, Siraj (Ms=5.2, Mb=5.6 and Io=VII) -             Earthquake 11/6/1981, Golbaf (Ms=6.7, Mb=6.1 and Io=VII+) -             Earthquake 28/7/1981, Siraj (Ms=7.1, Mb=5.7and Io=IX) 3-1-1-25- Mosha reverse Fault Mosha is a fault with minimum 200 km in length and a trend of NW-SE and reverse mechanism. Reverse Mosha Fault is active and seismic. Present data shows following earthquake has occurred due to reactivation of Mosha Fault. -             Earthquake, 1665, Damavand extent with estimated magnitude Ms=6.5 and Io=VII -             Earthquake, 1802, Damavand and Mazandaran extent. -             Weak Earthquake of 20 Jun., 1811, Damavand. -             Weak Earthquake of Jun. , 1815, Damavand- Shemiranat with Ms=7.1 and Io=IX. -             -After shock, 6Apr. 1830, Damavand – Shemiranat, Io=VIII Epicenter of 10 Jun., 1974, Mb=4.3 (ISC and it is located on Mosha Fault). 3-1-1-26- Nahavand strike – slip Fault with dextral component (it is a part of Young Zagros Fault)  Nahavand Fault is a branch of Zagros Fault (Tchalenco and Brand, 1974) with a trend of NW-SE, 2.5 km from South West Nahavand City. This fault has a length of 65 km with mechanism of dextral strike – slip and high slope towards SW. In all parts of this path, Nahavand Fault is a boundary between High Zagros (to south Western) and Sanadaj – Sirjan Zone (to North East). Gamasiab River flows in a part of this fault .   3-1-1-27- Neyshabour Reverse Fault Neyshabour Reverse Fault has a trend of NW-SE and it passes through 3 km from North West of Neyshabour City. Locating of young reverse fault of Neyshabour is in Quaternary in a horrible earthquake, 1209 (Ms=7.6 and Io=X) and morphotectonic characteristics are indicative of activity in this fault during this earthquake. 3-1-2- Major Fault in Iran More than faults with recognized seismic history, some faults are in Iran which can not be characterized with a trend of earthquake event and thus their seismic history is not characterized currently. Young age and much length in their faults emplace them in seismic faults group. Characteristics of these fundamental, long and young faults have been implied below. 3-1-2-1- Ardal Fault Ardal Fault has a length of about 150 km and its dip is towards North East and NW-SE parallel to Zagros Thrust in extent of Ardal – Naghan. It is located along Ardal Fault, with some salt domes outcrop, to North East of the fault. 3-1-2-2- Indes Reverse Fault Indes Reverse Fault has a trend of NW – SE from 18 km of South west of Saveh City. Indes Fault has crossed young and old terraces and quaternary Alluvial Sediments in parts of its length and it has some triangular facet. It is likely related to earthquake in Dec. 19, 1980 (Ms=5.8 and Mb=5.6) and Dec. 22, 1980 (Ms=5.2 and Mb=5.5) and Salafchegan has occurred due to activity of Indes Fault. 3-1-2-3- Binaloud Thrust Binaloud Fundamental Thrust has a bended trend of NW-SE and a length about 92 km in south western slope of Binaloud Range, located in 15 km of Neyshabour, Kavar Shahr. Mechanism of this fault is thrust with a trend of NE. 3-1-2-4- Jorjafak Reverse Fault  Jorjafak Reverse Fault has a trend of NW-SE and a length of over 130 km to North West Kerman. Morphotectonic Characteristics of Jorjafak Fault has crossed through Quaternary Alluvial Sediments obviously and it indicates its seismicity well however there is no seismic data for this fault.   3-1-2-5- Dena Fault Dena Fault is a fault with a trend of NNW – SSE and a dip towards ENE which is located in western part of Dinar Mount. with a height of 4287m. From most important characteristics of Dena Fault is outcrop of some fault dome along its length. In path of this fault, in western part of Dena Mount., Zagun and Lalun Fm. (Cambrian) are driven on Cretaceous rocks (Sotude Nia, 1975). To North Dena Mount., they are driven on Cretaceous Rocks on desert and or Bakhtiari Fm. (Pliocene) in slope of Dareh Badami Mount. to western slope and Kamaneh Mount.. Length of recognized part in Dena is at least 110 km. 3-1-2-6- Dehshir Fault Dehshir Quaternary Fault is a fault with a trend of NW-SE and its rake is near to gravitational trend and mechanism is dextral strike – slip. Fault length of Dehshir is near to 350 km with Nain South West (To North Western) to south of Baneh and Kheir Abad and Chah Kavir of Sirjan. Dehshir Fault is a Quaternary Fault but because it is located in a desert plain, there is no seismic data from that. 3-1-2-7- Zagros Major Fault Zagros Major Fault is with a trend of NW-SE and revere Mechanism which is one of present fundamental faults in Iran which is correlated to geosuture in Sanadaj – Sirjan zone to North East and Zagros in South Western Part (Berberian and King, 1981). In a path of Zagros Major Fault, mechanism of fault is reverse. Fault dip is N130E in this part, towards NE (Driving of Macran on Zagros). In path of Zagros Fault, some braded rocks are seen and some depression lands are formed. 3-1-2-8- Zardkuh Fault Zardkuh Fault has a compressional fault with a trend of NW-SE and a dip towards NE and parallel to South Ardal Fault. Zardkuh Fault is with a minimum length of 130km as a part of border in High Zagros and folded Zagros. 3-1-2-9- Sarvestan Fault Sarvestan Fault is with a trend of NNW-SSE and a length of about 75 km to South East Kerman. Releasing stress in its northern sides has created a seismic gap along Gouk Fault and some destroyer earthquakes of Golbaf and Sirj in Sarvestan Fault in 20th. 3-1-2-10- Soltanieh Reverse Fault Soltanieh Reverse Fault is a fault with lengthy of 140 km and with a trend of W-SE which passes through 8 km of SSW in Soltanieh City. Dip of this part is towards SW and erosional wall of fault can be observed in all fault length. Likely, earthquake in 1803, Soltanieh, has been due to activity of reverse fault to Soltanieh. 3-1-2-11- Shadad Reverse Fault Shadad Reverse Fault is a fault from Quaternary with a bended trend of NW-SE which is located in 2.5 km from South Shahdad. Its dip is towards SW and Neogene detrital sediments are driven on Quaternary alluvial sediments (To East and North east) (Berberian et al., 1984). 3-1-2-12- Torqabeh Fault Zone        Torghabeh Fault is with a trend of NE-SE at the foot of Binaloud Range and with a length of 77 km from 15 km of Mashad City. Locating earthquake center is near to Torqabeh Fault and it is likely representative of weak activity in this fault in 20th century. 3-1-2-13- Naybad Fault  Naybad Fault is a young fault with a trend of N-S and a length near to 400 km. Shear in very young Quaternary sediments and gravitational displacements have been reported in various parts. So we can conclude mechanism of Nayband Fault is dextral strike – slip with dip-slip displacement component which is continued from past times (Mohajer – Ashajai, 1976). 3-2-Iran Plateau Seismicity One of fundamental data for dangerous evolution and familiarity to seismicity history and seismotectonic schematic of each zone and extent is clarified for survey of earthquake history. It is obvious that for reaching to seismic characteristics we should survey earthquake history along much gathering compilation. 3-2-1- historical earthquakes (before 20th) Our recognition from historical earthquake is limited to historical books and some writings about this field and unfortunately there is a little awareness about macroseismic epicenter in historical earthquake. Anyway, investigation about old writings for discovering historical earthquakes is an attempt for its certain points and it can be a good data for recognition of potential for seismicity in a zone and provided zone. Bog historical and old earthquakes are as short writings 3-2-1-1- big earthquakes in 11th Millenium B.C in Seimareh from Zagros       Earthquakes before 10,000 years B.C in Seimareh Zone results in a big body (near 7,500 m3