Investigation of the relationship between tectonic morphological indices and seismic acceleration in Indes, Aipak, Avaj and Kushk-e-Nusrat fault zones (northwest of Saveh)
Subject Areas :bahar Rezaei nahal 1 , Mohsen Pourkermani 2 * , M. Zare 3 , M. Dehbozorgi 4 , R. Nozaem 5
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Keywords: Central Iran, Active tectonic, Morphometric indices, Kooshk-e-Nosrat fault, Indes fault, Avaj fault, Aipak.,
Abstract :
The northwest zone of Saveh city is located in the Indes, Kooshk e Nosrat, Avaj, and Aipak fault zones. Indes, Kooshk e Nosrat, Avaj, and Aipak faults are considered the major faults in central Iran, which are also active in the Quaternary, and their last movements are attributed to the present time. Therefore, the estimation of morphometry to identify the effect of active tectonics on the tectonic evolution of drainage basins seems necessary. In this study, six important morphotectonic indices were analyzed including the longitudinal gradient of the river, asymmetry of the drainage basin, hypsometric integral, drainage basin shape, the ratio of the floor width to the valley height, and mountain front. To model the formation of basins in the studied area, Arc Hydro software (Arc GIS add-ins) was used based on data derived from a digital elevation model. Then, 6 morphotectonic indices were compiled and classified on each of the basins. Finally, the Active Tectonic Index (IAT) was calculated, according to which the study area was classified into 4 categories including very high, high, intermediate, and low tectonic activity. According to the IAT index, 5% of the study area shows very high tectonic activity, 25% of the studied area has high tectonic activity, 65% of it has average tectonic activity and about 5% of the tectonic activity is low. Moreover, seismic acceleration was prepared to confirm the result of morphological indices in the estimation and analysis of active tectonics in the region. In this study, the highest level of tectonic activity can be seen in the north-eastern part of the area. In most sectors, the level of activity is high and intermediate, which is related to the activity of Kooshk-e-Nosrat, Aipak, and Avaj faults.
نبوی، م. ح.، 1355 ، دیباچه ای بر زمین شناسی ایران ، 109 .
- Alavi, M., 1991. Sedimentay and Structural characteristics of the Paleo-Tethys remnants in northeastern Iran. Geological Society of America Bulletin, 103, 983.
- Alavi, M., 1994. Tectonics of the Zagros orogenic belt of Iran: new data and interpretations: Tectonophysics, 229, 211-238.
- Alavi, M., 1996. Tectonostratigraphic synthesis and structural style of the Alborz mountain system in northern Iran. journal Geodyn., 21, 1- 33.
- Nowroozi,A.A and Mohajer-Ashjai,A.,1985. Fault movements and tectonics of Eastern Iran:boundaries of the Lut plate Geophys.J.R.astr. Soc.,83, 215-237.
- Babaahmadi, A. and Safaei, H. and Yassaghi, A. and Vafa, H. and Naeimi, A. and Madanipour, S., 2010. A study of Quaternary structures in the Qom region, west central Iran, Journal of Geodynamics, 50 (5), 355-367.
- Altin, T.B. and Altin, B.N., 2011. Development and morphometry of drainage network in volcanic terrain, Central Anatolia, Turkey, Geomorphology 125, 485–503.
- Reddy, G.P.O. and Maji, A.K. and Gajbhiye, K.S., 2004. Drainage morphometry and its influence on landform characteristics in a basaltic terrain, Central India — a remote sensing and GIS approach, International Journal of Applied Earth Observation and Geo information 6, 1–16.
- Keller‚E.and pinter‚N.‚1996. Active tectonics‚Earth quakes‚uplift and ‚Earth sciencesseries‚prentice-Hall‚Newjersey.
- Keller, E.A. and Pinter, N., 2002. Active Tectonics: Earthquakes, Uplift, and Landscape (2ndEd.) Prentice Hall, New Jersey.
- Molin, P. and Pazzaglia, F.J. and Dramis, F., 2004. Geomorphic expression of active tectonics in a rapidly-deforming forearc, sila massif, Calabria, southern Italy, American Journal of Science 304, 559–589.
- Silva, P.G., Goy and J.L., Zazo, C. and Bardajm, T., 2003, Fault generated mountain fronts in Southeast Spain: geomorphologic assessment of tectonic and earthquake activity, Geomorphology 250, 203–226.
- Hack, J.T., 1973, Stream-profiles analysis and stream-gradient index, Journal of Research of the U.S. Geological Survey 1, 421–429.
- Hack, J.T., 1982. Physiographic division and differential uplift in the piedmont and Blue Ridge. U.S. Geological Survey Professional Paper 1265, 1–49.
- Troiani, F. and Della Seta, M., 2008. The use of the stream length–gradient index in morphotectonic analysis of small catchments: a case study from Central Italy, Geomorphology 102, 159–168.
- Hack, J.T., 1957, Studies of longitudinal stream-profiles in Virginia and Maryland: U.S.Geological Survey Professional Paper 294B, 45–97.
- Hack, J.T., 1973. Stream-profiles analysis and stream-gradient index, Journal of Research of the U.S. Geological Survey 1, 421–429.
- Hack, J.T., 1982, Physiographic division and differential uplift in the piedmont and Blue Ridge. U.S. Geological Survey Professional Paper 1265, 1–49.
- Bull, W.B., 2007. Tectonic geomorphology of mountains: a newapproach to paleoseismology, Blackwell, Malden.
- El Hamdouni, R., Irigaray, C., Fernandez, T., Chacón, J. and Keller, E.A., 2007. Assessment of relative active tectonics, southwest border of Sierra Nevada (southern Spain), Geomorphology, 96, 150–173.
- Hare, P.W. and Gardner, T.W., 1985. Geomorphic indicators of vertical neotectonism along converging plate margins, Nicoya Peninsula, Costa Rica. In: Morisawa, M., Hack, J.T.
- Keller, E.A. and Pinter, N., 2002. Active Tectonics: Earthquakes, Uplift, and Landscape (2ndEd.) Prentice Hall, New Jersey.
- Dehbozorgi, M. and Pourkermani, M. and Arian, M.and Matkan, A. A. and Motamedi, H. andHosseiniasl, A., 2010, Quantitative analysis of relative tectonic activity in the Sarvestan area, central Zagros, Iran,Geomorphology, 121(3), 329-341.
- Strahler, A.N., 1952, Hypsometric (area–altitude) analysis of erosional topography, Geological Society of America Bulletin 63, 1117–1142.
-Mayer, L., 1990. Introduction to Quantitative Geomorphology, Prentice Hall, Englewood, Cliffs, NJ.
- Ramírez-Herrera, M.T., 1998. Geomorphic assessment of active tectonics in the Acambay Graben, Mexican volcanic belt, Earth Surface Processes and Landforms 23, 317–332.
- Cannon, P.J., 1976. Generation of explicit parameters for a quantitative geomorphic study of Mill Creek drainage basin, Oklahoma Geology Notes 36 (1), 3–16.
-Bull, W.B. and McFadden, L.D., 1977. Tectonic geomorphology north and south of the Garlock fault, California, In: Doehring, D.O. (Ed.), Geomorphology in Arid Regions,Proceedings of the Eighth Annual Geomorphology Symposium, State University of NewYork, Binghamton, 115–138.
- Keller, E.A., 1986. Investigation of active tectonics: use of surficial Earth processes. In:Wallace, R.E. (Ed.), Active tectonics Studies in Geophysics, National Academy Press,Washington DC, 136–147.
- Rockwell, T.K.and Keller, E.A. and Johnson, D.L., 1985, Tectonic geomorphology of alluvial fans and mountain fronts near Ventura, California. In: Morisawa, M. (Ed.), Tectonic Geomorphology, Proceedings of the 15th Annual Geomorphology Symposium. Allen and Unwin Publishers, Boston, 183–207.
- Azor, A., Keller, E.A. and Yeats, R.S., 2002. Geomorphic indicators of active fold growth:South Mountain–Oak Ridge Ventura basin, Southern California, Geological Society of America Bulletin 114, 745–753.
- Molin, P., Pazzaglia, F.J. and Dramis, F., 2004. Geomorphic expression of active tectonics in a rapidly-deforming forearc, sila massif, Calabria, southern Italy, American Journal of Science 304, 559–589.