تحلیل واکنش تعادلی رودهای منطقة دامغان در برابر رخدادهای تکتونیکی و فرسایشی با استفاده از مدل SPL

نوع مقاله : مقاله کامل

نویسندگان

1 استاد ژئومورفولوژی، دانشکدة جغرافیا، دانشگاه تهران

2 دانشیار ژئومورفولوژی، دانشکدة جغرافیا، دانشگاه تهران

3 استاد زمین ‏شناسی (تکتونیک)، پژوهشکدة علوم ‏زمین، سازمان زمین ‏شناسی و اکتشافات معدنی کشور

4 دانشیار زمین‏ شناسی، دانشکدة جغرافیا، دانشگاه تهران

5 دانشجوی دکتری مخاطرات ژئومورفولوژیک، دانشکدة جغرافیا، دانشگاه تهران

چکیده

لندفرم‏ها و واکنش‏ آن‏ها به تغییرات محیطی از جمله مباحثی است که از دیرباز مورد توجه متخصصان علم ژئومورفولوژی بوده‏ است. یکی از لندفرم‏هایی که از تغییرات محیطی به‏ویژه فرایندهای زمین‏ساختی و فرسایشی تأثیر می‏پذیرد رودخانه‏ها هستند. هدف اصلی در این پژوهش تحلیل واکنش رودهای ناحیه برای رسیدن به نیمرخ تعادلی در مواجهه میان فرایندهای زمین‏ساختی با فرایندهای فرسایشی است. برای این پژوهش، سه رود اصلی ناحیه شامل آستانه، چشمه‏علی، و تپال بررسی شد. رابطة توان برشی رود در قالب ارتباط میان شیب و مساحت زهکشی، مقادیر دو پارامتر تندی و فرورفتگی کانال را استخراج می‏نماید. هر دوی این پارامترها متأثر از عوامل سنگ‏شناسی، زمین‏ساختی، توپوگرافی، و فرسایشی‏اند. نتایج حاصل از بررسی سه رود اصلی منطقه نشان می‏دهد که رسیدن به نیمرخ تعادلی در هر رود به عوامل بالاآمدگی نسبت به سطح اساس، فرسایشی، و سنگ‏شناسی بستگی دارد. بالاآمدگی رخ‏دادة ناشی از گسل‏خوردگی آبراهه به افزایش ارتفاع و شیب کانال رود منجر شده و فرسایش در پاسخ به این تغییر در محیط رودخانه رخ می‏دهد. این امر باعث افزایش بار رسوبی تولیدی و در نتیجه بالارفتن بازده فرسایشی در رودها می‏‏شود. با افزایش بار رسوبی در پایین‏دست حوضه، رود قادر می‏شود تأثیر بالاآمدگی‏های گسلی بر بستر خود را خنثی کند.

کلیدواژه‌ها


عنوان مقاله [English]

Analysis of Equilibrium Response of Damghan Area Rivers to Tectonic and Erosion processes using SPL Model

نویسندگان [English]

  • Mojtaba Yamani 1
  • Abolghasem Goorabi 2
  • Mohammad Ghassemi 3
  • S.M Zamanzadeh 4
  • Fatemeh Kiaroostami 5
1 University of Tehran- Faculty of Geography
2 Department of Physical Geography
3 Teacher at the Research Institute for Earth Sciences, Geological Survey of Iran
4 U. T
5 Department of physical geography, university of Tehran, Tehran . Iran
چکیده [English]

Introduction:
Landforms and their response to environmental changes is one of the most interested topics among geomorphologists. One of the landforms that is most affected by tectonic and erosion processes is the rivers. Rivers respond to tectonic processes that increase the height of landscapes and erosion processes that try to reduce the height of landforms. This reaction can be well studied by analyzing the longitudinal profile of the rivers. One of the effective parameters in the study of tectonic and erosional status of regions is steepness and concavity. These parameters can be examined in the form of Stream Power Law (SPL). This function is related to incision power of streams.This relationship in the form of the linkage between slope and drainage area of the river in a logarithmic plot based on power regression, extracts the values of two parameters, the steepness and the concavity of the channel. In fact experimental studies by other researchers have shown that there is a direct relationship between rivers steepness and concavity with tectonic – erosive processes in the regions.
It generally accepted that steep landscape are associated with areas of high uplift rate and active tectonic. Rivers system are well adopted to tectonic processes to provide useful information about the rate of uplift in landforms. The steepness of rivers which depends on the declivity of channels is fraction of uplift rate. So we expect that if the amount of the steepness in the longitudinal profile of the river is low, the uplift rate is slight too and if the steepness is high, the uplift rate is intense too. Concavity index usually depends on bed material. But erosion efficiency has direct connection with incision power law and its steepness. But weakness of bed material especially alluvial can increase rate of erosion efficiency in channels. Erosion efficiency is the volume of sediment that is completely removed from the environment after erosion. Erosion efficiency is a function of sedimentary flux. This parameter can be directly related to the tectonic processes and characteristics of the bedrock. If tectonic processes lead to an increase in the height of the landforms, it can increase orographic precipitation in mountainous areas, and it can lead to increasing sedimentary flux, then erosion efficiency also increases. The main purpose of this study is to analysis the effect of active tectonic and erosion on equilibrium profile of the main rivers of the Damghan Mountain based on the Stream Power Law. These steepness and concavity parameters are influenced by set of lithological, geological, topographic and erosion factors. All of these factors are effective in location of knick points of rivers and are able to provide useful information about the geological and erosion status of the area
Material and Method: In order to investigate the power incision law, the DEM map in 30m resolution was used to extract the channels. For extracting the rivers, the D8 algorithm method was used to calculate the flow direction. In this method, the flow path of each pixel that fall on the lower pixel with a lower slope was calculated and the flow directions was determined. In this regard, we first need to create a DEM map with the least inconsistency. This method focuses on extracting central flows in valleys and reducing parallel flows. After extracting the channels, their slope-area logarithmic diagram were plotted. The regression line considered for the logarithmic plot is the power regression, which is the relation of the river incision power. In this regression, the slope of the regression line is concavity and the intercept of line is steepness. To obtain information about lithological features of the area that are effective in analyzing the concavity and steepness parameters, the geological map of Damghan and Shahrud was used. The study area is part of the mountain structure of Eastern Alborz and has several active faults. North Damghan Mountain is located on the southern side of eastern Alborz between 36。14'0.3" to 36。18' 82" and 55。00' 26" to 53。59' 56" in north of Iran plateau. There are different outcrops of lithostratigraphic formations from Precambrian to Quaternary in this area. Geologically speaking, the study area is composed of set of over thrust blocks and nappes. The thrust faults and nappes within piggy back style have pushed eastern Alborz stratigraphy sequences on each other. The folds in the region have a strong connection to thrust structures and nappes. These folds are of different types and sizes but most of them are inclined and recumbent because of widespread compressive component in eastern Alborz.
Result and Discussion: The three main rivers of the region, CheshmehAli, Astaneh and Tepal, were studied. All three rivers flow on the colluvium bed in the upstream and alluvial bed in the downstream. And all three affected by faults in some areas. Some such as CheshmehAli River in the southern part, has flowed into a fault valley. The activity of faults along the rivers, both in the resistance and alluvial parts has led to uplift of the rivers. These effects are seen in the high values of steepness index and low values of concavity index. The increase in the stream incision is seen in both the upper and lower section of the rivers due to the activity of faults in the region. But the steepness is higher in the upstream which is made of colluvium sediments. While in the downstream due to weakness of alluvial sediments the rate of erosion efficiency is higher. Therefore the change in the rate of steepness, concavity and erosion efficiency, in addition to active tectonic, is strongly affected by the bedrock of channels. Each rivers that is most faulted also has higher values of the steepness index. CheshmehAli River, part of which is located completely in the faulted valley, has the highest rate of steepness compared to other rivers. The Astaneh River has been affected by the Astaneh fault in several parts, and the fault has led to the uplift of the river by cutting off the Quaternary sediments. The high values of steepness parameter in this river confirm existence of active tectonic. The Tepal River in its upper part shows high values of steepness parameter, but in the downstream part where the river flows on agricultural lands, the rate of erosion efficiency has increased and in contrast the rate of steepness parameter has decreased. This is due to human activities that have caused the rate of erosion to exceed the rate of tectonic processes. Therefore, human activities are able to transform the relationships between internal and external processes that are effective in changing landforms.
Conclusion: The results show that reaching the equilibrium profile in each river depends on a set of factors include erosion, tectonic and lithology. Fault in the channel path leads to an increase in the height and slope of the river channel and erosion accurse in response to this change. Tectonic processes increase the incision capacity of rivers as a result of increasing the slope of the channel, which increase the volume of sediments produced in the river. Of course, like that Tepal River, we must consider the role of human activities in increasing the rate of erosion efficiency.

Key Words: Eastern Alborz, Damghan, Active Tectonic, Morphotectonic, SPL Model.

کلیدواژه‌ها [English]

  • Eastern Alborz
  • Damghan
  • active tectonic
  • Morphotectonic
  • SPL Model
امیدی، پ. (1380). تحلیل ساختاری و دینامیکی تفضیلی زون‏های گسلی در حاشیة جنوبی البرز خاوری (گسترة سمنان-دامغان)، رسالة دکتری، دانشکدة علوم پایه دانشگاه تربیت مدرس.
خادمی، م. (1376). بررسی و تحلیل ساختاری گسل‏های دامغان و عطاری در گسترة دامغان، پایان‏نامة کارشناسی‏ ارشد، دانشکدة علوم پایه دانشگاه تربیت مدرس.
درویش‏زاده، ع. (1370). زمین‏شناسی ایران، تهران: دانش امروز.
رحیمی، ب. (1385). مطالعات ساختاری رشته‏کوه البرز در شمال دامغان، رسالة دکتری، دانشکدة علوم زمین دانشگاه شهید بهشتی.
صالحی راد،ر و علوی، م. (1354). گزارش نقشة زمین‏شناسی دامغان در مقیاس 1:100000.
قاسمی،م.ر.(1369) زمین شناسی، چینه شناسی و زمین شناسی ساختمانی ناحیه چهارده (البرز خاوری). دانشکده زمین شناسی دانشگاه تهران.
محمدنژاد آروق، و. (1390). تحلیل مقایسه‏ای تحول مخروط‏افکنه‏های دامنة جنوبی البرز شرقی، رسالة دکتری، دانشکدة جغرافیا دانشگاه تهران.
وزیری، م. (1380). گزارش نقشة زمین‏شناسی 1:100000 شاهرود.
Allen, M. B.; Ghassemi, M. R.; Shahrabi, M. and Qorashi, M. (2003). Accommodation of Late Cenozoic Oblique Shortening in the Alborz Range, Northern Iran, Journal of Structural Geology, 25(5): 659-572.
Allen, M.; Jackson, J. and Walker, R. (2004). Late Cenozoic Reorganization of the Arabia-Eurasia Collision and the Comparison of Short-Term and Long-Term Deformation Rates, TECTONICS, 23(2): 1-16
Ambili, A.; Sushma, P.; Nathani, B.; Achim, B.; Shahzad, F. and Deenadayalan, K. (2012). Tectonic versus Climate Influence on Landscape Evolution: A Case Study from the Upper Spiti Valley, NW Himalaya, Geomorphology, 145-146: 32-44.
Antoine, P.; Jean-Jacques, B.; Berillon, G. and Khaneghah, A. (2006). Tuf Calcaire et Séquence Alluviale En Contexte Tectonique Actif : La Formation de Baliran (Province Du Mazandaran, Iran), Quaternaire, 17(4): 321-331.
Berberian, M. (1976). Quaternary Faults in Iran, 39: 187-258.
Berberian, M. (1983). Continental Deformation in the Iranian Plateau (Contribution to the Seismotectonics of Iran, Part IV, 74p.
Berberian, M. and Yeats, R. S. (2001). Contribution of Archaeological Data to Studies of Earthquake History in the Iranian Plateau, Journal of Structural Geology, 23(2): 563-584.
Darvishzadeh, A. (1991). Geology of Iran. Danesh Emrouz. Iran. Tehran. (In Persian).
Djamour, Y.; Vernant, Ph.; Roger, B.; Nankali, R .; Jean-François, R.; Hinderer, J.; Hatam, Y.; Bernard, L.; Le Moigne, N.; Sedighi, M. and Khorrami, F. (2010). GPS and Gravity Constraints on Continental Deformation in the Alborz Mountain Range, Iran, Geophysical Journal International, 183(3): 1287-1301.
Dong, Y.; Qi Li, A. D, and Xiaoqing, W. (2011). ‘Extracting Damages Caused by the 2008 Ms 8.0 Wenchuan Earthquake from SAR Remote Sensing Data’. The 2008 Wenchuan Earthquake, China and Active Tectonics of Asia 40(4):14-907. doi: 10.1016/j.jseaes.2010.07.009.
Fehr, E.; Andrade, J.r.; Sharon, C; da Silva, L. R.; Herrmann, H. J.; Kadau, D.; Moukarzel, C. and Oliveira, E.  (2009). New Efficient Methods for Calculating Watersheds, J. Stat. Mech., P09007 J. Stat. Mech 2009.
Hack, J.T. (1960). Interpretation of Erosional Topography in Humid Temperate Regions. Bobbs-Merrill.
Holbrook, J. and Schumm, S. A. (1999). Geomorphic and Sedimentary Response of Rivers to Tectonic Deformation: A Brief Review and Critique of a Tool for Recognizing Subtle Epeirogenic Deformation in Modern and Ancient Settings, Tectonophysics, 305(1): 287-306.
Hollingsworth, J.; Jackson, J.; Walker, R. and Nazari, H. (2009). Extrusion Tectonics and Subduction in the Eastern South Caspian Region since 10 Ma: REPLY, Geology.
Hollingsworth, J.; Nazari, H.; Ritz, J.; Salamati, R.; Talebian, M.; Bahroudi, A.; Walker, R.; Rizza, M. and Jackson, J. (2010). 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, 115, B12313: 1-19.
Hooke, R. (1967). Processes on Arid-Region Alluvial Fans, Journal of Geology - J GEOL, 75: 438-460.
Howard, A. (1994). A Detachment-Limited Model of Drainage-Basin Evolution, Water Resources Research, 30(7):2261-2285.
Howard, A. and Kerby, G. (1983). Channel Changes in Badlands, GSA Bulletin, 94(6): 739-752.
Hunt, Ch B. (1988). Introduction. In Geology of the Henry Mountains, Utah, as recorded in the notebooks of G. K. Gilbert, Geological Society of America. 76-1875.
Jackson, J.; Keith, F. P; Mark, B.A. and Berberian, M. (2002).Active Tectonics of the South Caspian Basin. Geophys. J. Int. (2002) 148, 214-245
Javidfakhr, B. and Ahmadian, S. (2018). Geomorphic and Structural Assessment of Active Tectonics in NW Alborz, Geopersia, 8(2): 261-278.
Keller, E. and Pinter, N. (1996). Active Tectonics: Earthquakes, Uplift, and Landscape, Prentus Hall. Newjersy.
Khademi, M. (1997). Structural Analysis of Damghan and Attari Faults in Damghan Range. Iran: Master Thesis, Supervisor: MohamadReza Samadian. Factually of Science. Tarbiat Modarres University. (In Persian).
Kirby, E. (2001). Quantifying Differential Rock-Uplift Rates via Stream Profile Analysis, Geology, 29.415-418.
Lague, D. and Davy, Ph. (2003). Constraints on the Long-Term Colluvium Erosion Law by Analyzing Slope-Are a Relationships at Various Tectonic Uplift Rates in the Siwalik Hills (Nepal), Journal of Geophysical Research, 108: ETG-18-1.
Lu, P. and Shang, Y. (2015). Active Tectonics Revealed by River Profiles along the Puqu Fault, Water Resources Research, 7: 1628-1648.
Miliaresis, G. (2001). Extraction of Bajadas from Digital Elevation Models and Satellite Imagery, Computers & Geosciences, 27: 1157-1167.
Mudd, S.; Clubb, F.; Gailleton, B. and Hurst, M. (2018). How Concave Are River Channels?, Earth Surface Dynamics Discussions, 6: Pp.1-34.
Mohammad Nejad Arogh, V. (2012). Comparative Analysis of the Cone Transformation of the Southern Slopes of the Eastern Alborz (Damghan to Garmsar). Doctoral Dissertation, Supervisor: Mojtaba Yamani. Factually of Geography. University of Tehran. (In Persian).
Mahmood, S. A. and Gloaguen, R. (2012). Appraisal of Active Tectonics in Hindu Kush: Insights from DEM Derived Geomorphic Indices and Drainage Analysis, Geoscience Frontiers, 3:407-428.
Montgomery, D. R.; Tim, B. A.; Buffington, J.; Peterson, N.; Schmidt, K.M. and Stock, J.D  (1996). Distribution of Bedrock and Alluvial Channels in Forested Mountain Drainage Basins, Nature, 381(6583): 587-589.
Nicholson, Ui.; VanLaningham, S. and Macdonald, D. (2013). Quaternary Landscape Evolution over a Strike-Slip Plate Boundary: Drainage Network Response to Incipient Orogenesis in Sakhalin, Russian Far East, Geosphere, 9: 588-601.
Omidy, P. (2002). Detailed Structural and Dynamic Analysis of Fault Zones in the Southern Margin of East Alborz (Semnan-Damghan Region), Doctoral dissertation. Supervisor: AliAkbar Nogolsadat. Factually of Science. Tarbiat Modarres University. (In Persian).
Pourramezani, A. and Bourzoie, S. (2017). ‘Study of Tectonic Activity in Young Eastern Alborz, Central Iran on the Basis of Alluvial Fans in the Shahrud-Bastam Area’, Open Journal of Geology, 7(1): 69-82.
Rahimi, B. (2002). Structural studies of Alborz Mountains in northern Damghan. Doctoral Dissertation. Supervisor: Sohrab Shahriyari. Factually of Science. Shahid Beheshti University. (In Persian).
Rizza, M.; Mahan, S.; Ritz, J. F.; Nazari, H.; Hollingsworth, J. and Salamati, R. (2011). Using Luminescence Dating of Coarse Matrix Material to Estimate the Slip Rate of the Astaneh Fault, Iran, Quaternary Geochronology, 6(3):390-406.
Salehirad Rad ,R  and Alavi, M. (1975). Geology Map of Damghan in 1:100000. (In Persian).
Seidl, M. and Dietrich, W. (1993). The Problem of Channel Erosion into Bedrock, Catena Suppl, 23: 101-24.
Shahzad, F.; Mahmood,S.A. and Gloaguen,R. (2009). ‘Drainage Network and Lineament Analysis: An Approach for Potwar Plateau (Northern Pakistan)’. Journal of Mountain Science 6:14–24. doi: 10.1007/s11629-009-0206-4.
Shahzad, F. and Gloaguen, R. (2011). TecDEM: A MATLAB Based Toolbox for Tectonic Geomorphology, Part 1: Drainage Network Preprocessing and Stream Profile Analysis, Computers & Geosciences, 37(2): 250-260.
Sklar, L, and Dietrich, W. (1998). ‘River Longitudinal Profiles and Bedrock Incision Models: Stream Power and the Influence of Sediment Supply’. Washington DC American Geophysical Union Geophysical Monograph Series 107:237-259. doi: 10.1029/GM107p0237.
Snyder, E.; Johnson, J.; Spyropolou, K.; Wobus, C.C.; Whipple ,K.; Kirby ,E.; Snyder ,N.; Johnson ,J.; Crosby ,B. and Sheehan ,D. (2006). Tectonics from Topography: Procedures, Promise, and Pitfalls, Geological Society of America Special Paper, 398: 55-74.
Snyder, N.P. and Whipple, K. (2000). Landscape Response to Tectonic Forcing: Digital Elevation Model Analysis of Stream Profiles in the Mendocino Triple Junction Region, Northern California, Geological Society of America Bulletin - GEOL SOC AMER BULL, 112. 1250-1263.
Stoc, j. and Montgomery,R. 1999. ‘Geologic Constraints on Bedrock River Incision Using the Stream Power Law’. JOURNAL OF GEOPHYSICAL RESEARCH, 104:93-4983.
Stoecklin, J. (1974). Northern Iran: Alborz Mountains. In: Spencer, A.M., Ed., Mesozoic-Cenozoic Orogenic Belts; Data for Orogenic Studies; Alpine-Himalayan Orogens, Special Publication, Geological Society, 4(1): 213-234.
Vassilakis, E.; Skourtsos, E. and Kranis, H. (2007). Estimation of Tectonic Uplift Rate Using Quantified Morphometric Indices. 8TH PAN-HELLENIC GEOGRAPHICAL CONFERENCE: 17-26.
Vaziri, M. (2001). Geology Map of Shahrud in 1:100000. (in Persian).
Vernant, Ph.; Nilforoushan, F.; Chéry, J.; Bayer, R.; Djamour, Y.; Masson, F.; Nankali, H.; Ritz, J. F.; Sedighi, M. and Tavakoli, F. (2004). Deciphering Oblique Shortening of Central Alborz in Iran Using Geodetic Data, Earth and Planetary Science Letters, 223(1): 177-185.
Wang, Y.; Zhang, H.; Zheng, D; Jingxing, Y; Jian-Zhang, P. and Yan, M (2017). Coupling Slope–Area Analysis, Integral Approach and Statistic Tests to Steady-State Bedrock River Profile Analysis, Earth Surface Dynamics, 5: 145-160.
Whipple, K.; Wobus, C.; Crosby, B.; Kirby, E. and Sheehan, D. (2007). New Tools for Quantitative Geomorphology: Extraction and Interpretation of Stream Profiles from Digital Topographic Data, Geol. Soc. Am. Annu. Meet. Course Notes, 1. Sponsored by: NSF Geomorphology and Land Use Dynamics.1-26.
Whipple, K.; Gregory, S.; Hancock, S. and Robert S. A. (2000) River Incision into Bedrock: Mechanics and Relative Efficacy of Plucking, Abrasion, and Cavitation, GSA Bulletin, 112(3): 490-503.
 Whipple, K. and Tucker, G. (2002). Implication of Sediment-Flux-Dependent River Incision Models for Landscape Evolution, Journal of Geophysical Research (Solid Earth), 107(B2): 1-20.
 Wohl, E. E. (1993). Bedrock Channel Incision along Piccaninny Creek, Australia, The Journal of Geology, 101(6): 749-761.