Seismotectonic of the Eastern Alborz with a Point of View to the South of Damghan MW=5.7 Earthquake

Nemati, M.; Hatzfeld, D.; Gheitanchi, M. R.; Talebian, M.; Mirzaei, N.; Sadidkhouy, A.

doi:10.22071/gsj.2012.54070

Document Type : Original Research Paper

Authors

¹ Assistant Professor, Faculty of Science & Earthquake Research Center, Faculty of Physics, Shahid Bahonar University of Kerman, Kerman, Iarn

² Professor, Laboratoire de G´eophysique Interne et Tectonophysique, CNRS, UJF, Grenoble, France

³ Professor, Institute of Geophysics, University of Tehran, Tehran, Iran

⁴ Assistant Professor, Institute for Earth Science, Geological Survey of Iran, Tehran, Iran

⁵ Associate Pprofessor, Institute of Geophysics, University of Tehran, Tehran, Iran

⁶ Assistant Professor, Institute of Geophysics, University of Tehran, Tehran, Iran

https://doi.org/10.22071/gsj.2012.54070

Abstract

The Shahroud fault system plays important role in seismotectonic of the eastern Alborz. In this paper we have surveyed the seismicity of the middle-eastern Alborz and its southern area. At this investigation, the data of the Geological Survey of Iran local seismological networks, the seismological networks of the Institute of Geophysics of the University of Tehran and the International Institute of Earthquake Engineering and Seismology of Iran were used for processing the focal mechanism of micro-earthquakes and the south of Damghan earthquake and its greatest aftershock. Distribution of the micro-earthquakes and the south of Damghan events epicenters indicate intense activity of the Shahroud fault system and the Toroud fault. Focal mechanisms of them shows near vertical dipping of the faults and left lateral mechanism of the western segments of the fault system and the Toroud fault. The focal mechanisms suggest the Astaneh, Chashm and Firouzkuh faults from the system fault behave in a same manner with no deference between them at depth and have seismic potential proportion to their total length. Also due to left lateral mechanism of the south of Damghan earthquakes, Toroud fault treats like of the eastern Alborz seismotectonically and this area could cover Toroud fault.

Keywords

20.1001.1.10237429.1391.22.86.12.2

References

References

Allen, M. B., Ghassemi, M. R., Shahrabi, M. & Qorashi, M., 2003- Accommodation of late Cenozoic oblique shortening in the Alborz range, Iran, J. Struct. Geol., 25, 659–672.

Ambraseys, N. & Melville, C., 1982- A History of Persian Earthquakes, Cambridge University Press.

Berberian, M. & King, G. C. P., 1981- Towards a paleogeography and tectonic evolution of Iran, Canadian J. Earth Sci., 18, 210–265.

Berberian, M. & Yeats, R. S., 1999- Patterns of Historical Earthquake Rupture in the Iranian Plateau, Bull. Seism. Soe. Am., 89,120-139.

Berberian, M., 1983- The southern Caspian: a compressional depression floored by a trapped, modified oceanic crust, Canad. J. Earth Sci., 20, 163–183.

Engdahl, E. R., Vander Hilst, R. D. & Buland, R. P., 1998- Global teleseismic earthquake relocation with improved travel time sand procedures for depth determination. Bull. Seism. Soc. Am. 88, 722–743.

Fattahi, M., Walker, R., Khatib, M. M., Dolati A. & Bahroudi A., 2007- Slip-rate estimate and past earthquakes on the Doruneh fault, eastern Iran R. T. Walker. Geophys. J. Int. (2007) 168, 691–709.

Graymer, R. W., Langenheim, V. E., Simpson, R. W., Jachens, R. C. & Ponce, D. A., 2007- Relatively simple through-going fault planes at large-earthquake depth may concealed by the surface complexity of strike-slip faults, Geol. Soc. London Spec. Publ., 290, 180-201. doi:10.1144/SP290.5.

Harvard, 2010- Department of Geological Sciences, Centroid Moment Tensor catalogue, http://www.seismology.harvard.edu/CMTsearch.html.

Havskov, J. & Ottemöller, L., 2005- SEISAN: The earthquake analysis software, version 8.1.

Hessami, K., Jamali, F. & Tabassi, H., 2003- Map of Major Active Faults of Iran, Tech. rep., International Institute of Earthquake Engineering and Seismology, Iran, http://www.iiees.ir.

Hollingsworth, J., Fattahi, M., Walker, R., Talebian, M., Bahroudi, A., Bolourchi, M. J., Jackson J. & Copley, A., 2010a- Oroclinal bending, distributed thrust and strike-slip faulting, and the accommodation of Arabia–Eurasia conver g ence in NE Iran since the Oligocene. Geophys. J. Int. doi: 10.1111/j.1365-246X.2010.04591.x.

Hollingsworth, J., Jackson, J., Walker, R. & Nazari, H., 2008- Extrusion tectonic and subduction in eastern South Caspian Region since 10 Ma, Geology, Vol. 36; no. 10; p. 763-766.

Hollingsworth, J., Jackson, J., Walker, R., Gheitanchi, M. & Bolourchi, M., 2006- Strike-slip faulting, rotation, and along-strike elongation in the Kopeh Dagh mountains, NE Iran: Geophysical Journal International, v. 166, p. 1161–1177, doi: 10.1111/j.1365-246X.2006.02983.x.

Hollingsworth, J., Nazari, H., Ritz, J.-F., Salamati, R., Talebian, M., Bahroudi, A., Walker, R.-T., Rizza, M. & Jackson, J., 2010b- Active tectonics of the east Alborz mountains, NE Iran: Rupture of the left lateral Astaneh fault system during the great 856 A.D. Qumis earthquake. journal of geophysical research, vol. 115, B12313.

http://www.geo.uib.no/Seismologi/SOFTWARE/

http://www.guralp.com/

http://www.soest.hawaii.edu/gmt/

Klinger, Y., 2010- Relation between continental strike-slip earthquake segmentation and thickness of the crust, J. Geophys. Res., 115, doi: 10.1029/2009JB006550.

Lee, W. H. K. & Lahr, J. C., 1972- HYPO71 (revised), A computer program for determining hypocenters, magnitude and first motion pattern of local earthquakes, U. S. Geol. Surv. Open File Rep., 75–311.

Manighetti, I., Campillo, M., Bouley, S. & Cotton, F., 2007- Earthquake scaling, fault segmentation, and structural maturity, Earth Planet. Sc. Lett., 253, 429-438.

Masson, F., Che´ry, J., Htzfeld, D., Martinoid, J., Vernant, P., Tavakoli, F. & Ghafory Ashtiani, M., 2005- Seismic versus aseismic deformation in Iraninferred fromearthquakes and geodetic data. Geophysical Journal International, 160, 217–226.

Nazari, H. & Ritz, J.-F., 2008- Neotectonics in Central Alborz, Geosciences, Special Issue, Vol. 17, N. 1. GSI, Tehran, Iran.

Nazari, H., 2006- Analyse de la tectonique récente et active dans l'Alborz Central et la région de Téhéran: Approche morphotectonique et paléoseismologique, unpublished PhD thesis, University of Montpellier II, pp.247.

Nazari, H., Ritz J-F., Salamati, R., Balescu, S., Michelot J-L. & Ghorashi, M., 2008- Paleoseismological analysis in Tehran area (Central Alborz, Iran), SGF, Dynamique d'une collision continentale, l' Iran, 6-7 Octobre 2008,Paris.

Nazari, H., Ritz, J-F., Walker, R., Alimohammadian, H., Salamati, R., Shahidi, A., Patnaik, R. & Talebian M., 2009- Chronology of last earthquake on Firouzkuh Fault using by C14, Geophysical Research Abstracts, Vol. 11, EGU2009-4906, EGU General Assembly 2009.

Ritz, J. F., Balescu, S., Sleymani, S., Abbassi, M., Nazari, H., Feghhi, K., Shabanian, E., Tabassi, H., Farbod, Y., Lamothe, M., Michelot, J.L., Massault, M., Che´ry, J. & Vernant, P., 2003- Geometry, kinematics and slip rate along the Mosha active fault, central Alborz: Nice, France, EGU-AGU-EUG Joint Assembly, Abstract EAE03-A-06057.

Ritz, J.-F., Nazari, H., Ghassemi, A., Salamati, R., Shafei, A., Solaymani, S. & Vernant, P., 2006- Active transtension inside central Alborz: A new insight into northern Iran–southern Caspian geodynamics, Geology, v. 34, p. 477–480, doi:10.1130/G22319.1.

Scholz, C., 1982- Scaling laws for large earthquakes: consequences for physical models, Bull. Seism. Soc. Am., 72, 1-14.

Schwartz, D. P. & Coppersmith, K. J., 1984- Fault behavior and characteristic earthquakes: Examples from the Wasatch and San Andreas fault zones, J. geophys. Res., 89, 5681-5698.

Sengo¨r, A. M. C., Altiner, D., Cin, A., Ustaomer, T. & Hsu, K. J., 1988- Origin and assembly of the Tethyside orogenic collageatthe expense of Gondwana Land. Gondwana and Tethys. In: Audley-Charles, M. G., Hallam, A. (Eds.), Geological Society Special Publication, 37, pp. 119–181.

Sibson, H. R., 1975- Generation of pseudotachlyte by ancient seismic faulting. Geophys. J.R. astr. Soc., 43, 775-794.

Sibson, H. R., 1974- Frictional constraints on thrusts, wrench and normal faults. Nature, 249(5454), 542-541.

Sibson, H. R., 1977- Fault rocks and fault mechanics. J. Geol. Soc. London, 133, 191-213.

Solaymani Azad, S., 2009- Seismic Hazard Assessement for Tehran, Tabriz and Zandjan Cities (NW Iran) Based on Morphotectonics and paleoseismology, PhD Thesis, University of Montpellier2 (France), PP. 150 (in French).

Stöcklin, J., 1974- Northern Iran: Alborz mountains, in Mesozoic–Cenozoic Orogenic Belts: Data for Orogenic Studies, pp. 213–234, ed. Spencer, A., Geol. Soc. Spec. Publ. London, Vol. 4.

Tatar, M., Jackson, J., Hatzfeld, D. & Bergman, E., 2007- The 2004 May 28 Baladeh earthquake (Mw 6.2) in the Alborz, Iran: over thrusting the South Caspian Basin margin, partitioning of oblique convergence and the seismic hazard of Tehran, Geophys J. Int., 170, 249–261.

Tchalenko, J. S., Berberian, M., Iran manesh, H., Bailly, M. & Arsovsky, M., 1974b- Tectonic Framework of the Tehran region, Geological Survey of Iran, Report no. 29.

Tchalenko, J. S., Braud, J. & Berberian, M., 1974a- Discovery of three earthquake faults in Iran. Nature, 248, 661–663.

Vernant, P., Nilforoushan, F., Hatzfeld, D., Abassi, M., Vigny, C., Masson, F., Nankali, H., Martinod, J., Ashtiani, A., Bayer, R., Tavakoli, F. & Che´ry, J., 2004b- Contemporary crustal deformation and plate kinematics in Middle East constrained by GPS measurements in Iran and northern Oman, Geophys. J. Int., 157, 381–398.

Vernant, Ph., Nilforoushan, F., Che´ry, J., Bayer, R., Djamour, Y., Masson, F., Nankali, H., Ritz, J.-F., Sedighi, M. & Tavakoli, F., 2004a-Deciphering oblique shortening of central Alborz in Iran using geodetic data, Earth and Planetary Science Letters, 223, 177–185.

Wenousky, S. G., 1988- Seismological and structural evolution of strike-slip faults, Nature, 395, 340-343.

Wessel, P. & Smith, W. H. F., 1998- New, improved version of Generic Mapping Tools released, EOS, Trans. Am. Geophys. Un. 79(47), 579.

Scientific Quarterly Journal of Geosciences

Seismotectonic of the Eastern Alborz with a Point of View to the South of Damghan MW=5.7 Earthquake

References

References

Volume 22, Issue 86
December 2012
Pages 87-98

Seismotectonic of the Eastern Alborz with a Point of View to the South of Damghan MW=5.7 Earthquake

References

References

Volume 22, Issue 86December 2012Pages 87-98

Volume 22, Issue 86
December 2012
Pages 87-98