Z. Bakhtiarizadeh; H. Nazari; M. A. Shokri; A. Mahfroozi; A. Kaveh-firooz
Abstract
Archaeologists believe that men who lived in Archaeological sites of Mazandaran such as Komishan cave, Hutu and Kamarband, After leaving the cave were gradually formed the Gohar tappeh. Over time, people living with the loss of previous places were higher places. In Neolithic village has been form of ...
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Archaeologists believe that men who lived in Archaeological sites of Mazandaran such as Komishan cave, Hutu and Kamarband, After leaving the cave were gradually formed the Gohar tappeh. Over time, people living with the loss of previous places were higher places. In Neolithic village has been form of rural life there, and And the Bronze period considered and the state of urbanization has found. Archaeological studies dating this area back to seven thousand years and findings of the Bronze era (the third millennium), Iron II Age (mid-second millennium B.C.) unfold it. this study provided Archaeoseismology based on knowledge paleoseismological on the fault system of the Khazar in the protohistory area on Gohar tappeh in Behshahr of Mazandaran province. Field reviews of paleoseismological has been in the archeology trenches of the Gohar tappeh site and geophysical data (GPR and geoelectric) from this range is evaluated at the appropriate scale. On the basis of paleoseismology researches, five earthquake events in period of 3500 to 5000 past years, with magnitude of 7 -6.2 on the moment magnitude scale (Mw) detected. The maximum displacement of detected index in paleoseismological observations by the Geophysical perceptions and GPR data also confirmed. Moreover the average course back of earthquake events is estimated at about 375 years. According to Archaeoseismology researches conducted in area, occurrence of earthquake events has been identified that in Range a few hundred years ago Cause loss or migration and immigration of protohistorical Gohar Tappeh people.
M.A Shokri; M Foroutan; M Nemati; M.J Bolourchi; SH Javadipour; B Oveisi
Abstract
The Touchahi earthquake of Aug 27, 2010 (MN 5.9; IRSC- Mw 5.7; USGS) occurred at 19:23:49 UTC (23:53:49 local time on 5 Shahrivar 1389) in south of Damghan city. No foreshock were reported before this earthquake whereas 85 aftershocks (MN 1-5) were registered by IRSC until 1 month after the mainshock. ...
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The Touchahi earthquake of Aug 27, 2010 (MN 5.9; IRSC- Mw 5.7; USGS) occurred at 19:23:49 UTC (23:53:49 local time on 5 Shahrivar 1389) in south of Damghan city. No foreshock were reported before this earthquake whereas 85 aftershocks (MN 1-5) were registered by IRSC until 1 month after the mainshock. According to our field study after the event, surface rupture of causative fault was not observed but we measured some fractures related to this event with dominant strike of N120º-140º. According to our observations of 32 towns and villages that were damaged in this seismic event, maximum intensity (I0) of VIII+ in MMI scale occurred near the Touchahi village in ~85 km south of Damghan city. Unfortunately in this earthquake 4 people were killed. Focal mechanisms of the Touchahi seismic event and its greatest aftershock is solved using the first P motion method. The fault plane solution show near vertical plane for the causative fault of the earthquake and suggests a left- lateral mechnism. The mechanisms associated with the fault show mainly left-lateral strike–slip motion, on a NE –SW striking fault plane. Based on location of the earthquake epicenter, its aftershocks location, the fault plane solution (left-lateral strike-slip with N039º strike and dip direction toward NW) and field observations, the causative fault of Touchahi earthquake is one of the active fault branches that is situated in north of Darestan mountain and south of Touchahi, Koohzar and Kooshahi villages. This fault with left-lateral strike-slip mechanism by general strike of NE-SW and dip direction toward NW is indicated as Touchahi fault.
A. Kaveh Firouz; H. Nazari; M. Arian; A. Shafei; T. Majidi; M. Shokri
Abstract
The North Tehran Fault with a length of about 110 km in North of Tehran and soutern of central Alborz with W-E trend (N25˚E) and dipping (30˚NE) is located in western of Mosha Fault.The branch of Chitgar such as Milad and Vardavard Fault in the form of propagation fault is increased toward south. Previous ...
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The North Tehran Fault with a length of about 110 km in North of Tehran and soutern of central Alborz with W-E trend (N25˚E) and dipping (30˚NE) is located in western of Mosha Fault.The branch of Chitgar such as Milad and Vardavard Fault in the form of propagation fault is increased toward south. Previous morphotectonical investigation along the North Tehran Fault show that shear of quaternary sedimentation and pressure mechanism with left-lateral component. Determination of seismic parameter and seismic action that result of this fault movement, need to doing paleoseismological investigation. In this text with using stratigraphy correlation method, estimated of subsidence rate is 0.16 mm/yr and logging with ratio and ortho photography method, 3-6 event is determined with 6.4-7.4 magnitude and recurrence