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فهرست مطالب نویسنده:

mojtaba yamani

  • خبات امانی، سید موسی حسینی*، مجتبی یمانی، مهران مقصودی

    رودخانه ها سیستم های دینامیک ژئومورفولوژیک هستند که دائما در حال تغییر و تحول می باشند. این تغییر و تحولات بسته به شرایط توپوگرافیک، ژئومورفولوژیک، هیدرولوژیک و هیدرولیک متفاوت است. پژوهش حاضر با هدف کمی سازی تغییرات ژئومورفولوژیک رودخانه در سه بازه تقریبا 25 کیلومتری در طول رودخانه سفیدرود در استان های کردستان - بازه یساول؛ زنجان - بازه گیلوان و مازندران - بازه آستانه بررسی و ارتباط آن ها با شدت سیلاب انجام شده است. شدت سیلاب از ترکیب عمق و سرعت سیلاب با دوره بازگشت 25 ساله با مدلسازی هیدرولیکی به وسیله نرم افزار HEC RAS در بازه های مورد مطالعه بدست آمد. چهار شاخص شریانی کانال (B)، سینوسیته کانال (P)، نرخ جابجایی جانبی(RM) و پایداری کانال رودخانه(S) در بازه های مورد مطالعه بدست آمدند.  نتایج حاصل موید آن است که شاخص شریانی بازه یساول به دلیل دخالت های کم تر انسان و وجود پشته های رسوبی و جریانات چند شاخه بیشتر از دو بازه دیگر است. شاخص سینوسیته بازه آستانه به دلیل مورفولوژی جلگه ای کناره ها بالاتر بود و میزان جابجایی جانبی این بازه نیز تحت تاثیر همان عامل بیشتر بود. دوبازه گیلوان و یساول به دلیل محدود بودن کناره ها پایداری بیش تر و سینوسیته و جابجایی جانبی کم تری داشتند. نتایج بررسی ارتباط شاخص های ژئوموفولوژیک رودخانه با شدت سیلاب با دوره بازگشت های میان مدت نشان داد که برخلاف انتظار، در نواحی با شدت سیلاب بیشتر تغییرات کانال رودخانه کمتر است. که دلایل عمده آن را می توان با تاثیرگذاری هندسه مقطع کانال و شیب طولی کانال رودخانه مرتبط دانست. چرا که از نظر مورفولوژیک در نواحی عمیق کانال رودخانه، امکان جابجایی کم تر است لذا رودخانه پایدارتر می باشد. همچنین در شیب های تند جریان رودخانه اعم از پایه و سیلابی سرعت و در نتیجه شدت بیشتری دارد و کانال را بیشتر حفر می کند. کانال عمیق تر قاعدتا توانایی عبور سیلاب های با دوره بازگشت کم تر را دارد و امکان سرریز شدن آب به اراضی مجاور و ایجاد مسیرهای جدید کاهش می یابد.

    کلید واژگان: ژئومورفولوژی کمی, شدت سیلاب, رودخانه سفیدرود, مدلسازی هیدرولیکی
    Khabat Amani, Seiyed Mossa Hosseini*, Mojtaba Yamani, Mehran Maghsoudi
    Introduction


    Rivers are dynamic geomorphological systems that continuously change due to various influencing parameters. Morphological changes in the river channel primarily involve adjustments in channel width, depth, slope, and river planform. The extent of lateral migration of the river channel depends on factors such as bank resistance to erosion, the duration and magnitude of flow, the curvature radius of the channel, and the flow capacity to transport sediments. Quantifying geomorphological changes in rivers with an emphasis on flood hydraulics requires detailed analysis and complex modeling of the dynamic interactions between water flow, sediment deposition, and riverbed alterations. Flood severity, characterized by high discharge, significant flow depth, and extreme flow velocities, can have substantial impacts on riverbed structures, including changes in depth, width, channel meanders, as well as sediment transport and deposition. The Sefidroud River is one of the largest rivers in Iran, directly and indirectly affecting the lives of a significant population. Throughout history, there has been a strong inclination to settle near this river, with numerous urban and rural settlements located along its course. The occurrence of frequent floods in the past and the river's tendency to alter its channel, especially in the lowland regions, make the delineation of floodplains and prediction of future river behavior essential aspects of this research. Therefore, identifying and quantifying the geomorphological changes of the Sefidroud River and investigating the relationship between these changes and flood severity during mid-term return periods are key objectives of this study.

     Results  :

    In the present study, four indices were calculated and used to quantify the river's morphological changes: channel braiding index (B), channel sinuosity index (P), lateral migration rate, and channel stability. The study reaches showed minimal variation in terms of the braiding index, with the Yasaval reach having the highest value, which is 0.07 higher than the Astaneh reach, which had the lowest value. The lower braiding indices of the Gilvan and Astaneh reaches, compared to Yasaval, can be attributed to the higher severity of human activities in the riverbed and the presence of the Sefidroud Dam upstream of the Astaneh branch. Regarding the channel sinuosity index (P), there is an inverse relationship between flow severity and shear stress with the sinuosity index. Reaches with lower flow severity and reduced shear stress tend to have higher sinuosity. Concerning the lateral migration rate, the results showed that this index is strongly influenced by the morphology and topography of the riverbanks. In the Yasaval and Gilvan reaches, which flow through mountainous regions, the lateral migration rate is lower (1.3 and 1.93, respectively) due to the rougher and more restrictive topography. The equations related to channel stability and migration rate indicate an inverse relationship: as the channel's migration increases, its stability decreases, and vice versa. Flood severity, which is the product of flow velocity and depth, can lead to significant changes in the river channel, meanders, and sediment distribution. The results indicate that, contrary to expectations, in areas with higher flood severity during a 25-year return period, river channel changes are less pronounced. This phenomenon is related to factors such as channel depth and longitudinal slope. Deeper channels, where flood severity is greater, exhibit higher stability and therefore experience fewer changes. In contrast, wider and shallower sections of the river, with slower flow, tend to undergo more substantial alterations.

     Discussion and Conclusion  :

    Numerous studies have been conducted on river morphology changes across various regions worldwide, employing a wide range of methods. In this study, several of these methods were used to quantify and examine the geomorphological changes in the selected study reaches. However, a key aspect of this research is the relationship between flood severity and geomorphological changes in rivers. Most studies in this field have focused on the impact of one or several extreme flood events on river channel changes, typically employing a before-and-after comparative approach. However, this research utilizes hydraulic modeling, based on validated 1:1000 maps and hydrometric data, to comprehensively examine the overall effect of flood severity on river morphology and channel changes. The results were then compared with geomorphological change maps, providing a broader perspective on the relationship between flood dynamics and river morphology.The results indicate that the braiding index of the Yasaval stretch is higher than the other two due to lower human interference and the presence of sediment bars and multi-threaded flows. The sinuosity index in the Astaneh stretch was higher due to the floodplain morphology of the riverbanks, which also contributed to a higher lateral migration rate. In contrast, the Gilvan and Yasaval stretches, with their more confined banks, showed greater stability and lower sinuosity and lateral migration rates.The study also examined the relationship between the geomorphological indices of the river and flood severity during mid-term return periods. Contrary to expectations, in areas with higher flood severity, channel changes were less pronounced. This can be attributed to the influence of channel geometry and longitudinal slope. In deeper sections of the river, morphological changes are less likely, resulting in greater stability. Additionally, in steeper slopes, both base flow and flood flows exhibit higher velocities, leading to greater channel incision. Deeper channels are more capable of handling floods with shorter return periods, reducing the likelihood of overflow and the formation of new channels.

    Keywords: Quantitative Geomorphology, Flood Severity, Sefidroud River, Hydraulic Modeling
  • محمد فتح الله زاده*، مجتبی یمانی، ابوالقاسم گورابی، مهران مقصودی، مهرنوش قدیمی

    مورفوتکتونیک، دانش کاربرد اصول ژئومورفیک در حل مسائل تکتونیکی است. رقابت مداوم بین فرآیندهای تکتونیکی که تمایل به ایجاد توپوگرافی دارند و فرآیندهای سطحی که تمایل به فرسایش و متلاشی کردن آنها دارند، اساس علم مورفوتکتونیک است. جلگه های ساحلی به دلیل عملکرد همزمان فعالیت های تکتونیکی بر دو محیط خشکی_آبی، دارای لندفرم ها و چشم اندازهای نوزمین ساختی قابل تمایزی هستند. مناطق ساحلی شمال ایران به دلیل تراکم بالای جمعیت و قابلیت رشد و توسعه اقتصادی و کشاورزی، از اهمیت بسیاری برخوردار است. یکی از روش های شناسایی و اندازه گیری تغییرات زمین استفاده از دورسنجی راداری است. اصول این تکنیک برای اولین بار توسط گراهام در سال 1974 بیان شد. در این پژوهش نوار ساحل شرقی دریای خزر از گمیشان تا جویبار از نظر فعالیت های تکتونیکی با استفاده از تکنیک های دورسنجی راداری در بازه زمانی 2014 تا 2021 مورد پایش قرار گرفت. اگرچه بازه زمانی انتخابی در مقیاس زمانی زمین شناسی کوچک محسوب می شود، اما شدت عملکرد فرایندهای تکتونیک در منطقه امکان تمایز مناطق فعال ساحلی را مشخص می کند. نتایج بدست آمده از تداخل سنجی راداری بیانگر آن است که بخش شرقی ساحل خزر بیشتر تحت تاثیر بالاآمدگی بوده و این روند تا خلیج گرگان ادامه دارد بطوری که محدوده شهر گرگان نرخ بالا آمدگی 20 تا 40 میلی متر در سال را تجربه کرده است. روند تغییرشکل به سمت ناحیه ساحلی معکوس شده و فرونشستی معادل 10 تا 52 میلی متر در سال را داشته است. با نزدیک شدن به کرانه خزر این نرخ کمتر شده و به 10 میلی متر در سال می رسد. با توجه به اینکه در نوار ساحلی خزر آب های سطحی فراوان بوده و بهره برداری از آب زیرزمینی در این مناطق بسیار اندک است، از این رو  با اطمینان بالایی می توان عامل رخداد بالاآمدگی و فروافتادگی (گمیشان) در این مناطق را به سازوکار تکتونیک و فعالیت گسل های فعال منطقه نسبت داد.

    کلید واژگان: مورفوتکتونیک, ساحل, جلگه خزر, تداخل سنجی راداری, ژئودینامیک
    Mohamad Fathollahzadeh *, Mojtaba Yamani, Abolghasem Goorabi, Mehran Maghsoudi, Mernoosh Ghadimi
    Introduction

    The landforms created by tectonic processes are studied by morphotectonics, in other words, morphotectonics is the science of applying geomorphic principles in solving tectonic problems. Quantitative landscape measurements are usually based on the calculation of geomorphic indices, using topographic maps, satellite images aerial photographs, and field visits. Coastal deltas are part of landforms and landscapes that, due to the proximity of two environments, land, and water, leave visible effects against tectonic activities, such as changing the pattern and location of deltas due to the change in the course of coastal rivers, the formation of unbalanced coastal terraces in parts of the coast, and the emergence of cut beaches in the form of seawalls.One of the methods of identifying and measuring land changes is using radar remote sensing. The principles of this technique were first described by Graham in 1974 (Pacheco et al., 2006). Interferometry using radar images with an artificial window or SAR is a precise method based on the use of at least two radar images of the same area, which measures the height displacement changes in wide areas and during different time intervals with a significant accuracy of millimeters (Dong et al., 2018).The coastal areas of northern Iran are of great importance due to the high population density and the ability to grow and develop economically and agriculturally, so monitoring geomorphic changes in the direction of sustainable development of these areas is particularly important.In this research, the eastern coast of the Caspian Sea from Gomishan to Joibar is investigated in terms of subsidence and uplift using radar remote sensing techniques to determine the active tectonic zones of the coast in terms of temporal and spatial changes.

    Materials and Methods

    The Eastern Caspian Plain is the border between the Caspian Sea and West Gorgan and includes the cities of Gomishan, Bandare Turkman, Bandare Gaz, Gulugah, Khazarabad, and Joybar. The absolute height of the Caspian Plain along the coastline is determined according to the sea level, based on the hydrographic data of the Baku station, since 1850, the Caspian sea level has varied between -25.4 and -29.4 (Abdolhi Kakrodi, 2012).The history of seismic activity in North Alborz shows that cities like Rasht, Lahijan, Amol, and Gorgan, have been destroyed many times due to destructive earthquakes (Aqhanbati, 2013). The Alborz fault is an active fault that is stretched in a clockwise direction in the southern Caspian basin.In this research, according to the desired goals and radar remote sensing techniques, a series of Sentinel-1 radar images with a suitable time and space difference (maximum 30 days and maximum 150 meters respectively) including 61 images in time from 2014 to 2021 were prepared and processed.

    Results

    The results obtained from the SBAS model indicate that the eastern part of the Caspian coast is more affected by the uplift and this trend continues up to Gorgan Bay. The Gorgan city has an uplift between 20 and 40 mm/year, which is reversed towards the coastal area, and subsidence of 10 to 52 mm/year occurs, which decreases as it approaches the coast and reaches 10 mm /year.

    Discussion and Conclusion

    According to the results obtained from radar interferometry, the eastern coast of the Caspian Sea is more affected by uplifting. The Gorgan city has an uplift between 20 and 40 mm/year, which is reversed towards the coastal area, and subsidence of 10 to 52 mm/year occurs, which decreases as it approaches the coast and reaches 10 mm/year.To verify the results obtained, the data of the Gorgan geodynamic station was used, which shows subsidence of about 90 to 100 mm in a 6-year period, which is consistent with the values obtained from radar interferometry Based on comments Shahpasandzadeh (2013) and the reports of Nazari et al (2021), active tectonics caused by the Caspian fault that indicates the horizontal geodynamic displacement diagram of Gorgan, the small area towards the north and east during this time, which is observed in the form of numerous branches with a thrust (reverse) mechanism and a right-slip component with a slope to the south in Golestan province.Considering that the main feature of the coast of the Caspian Sea is the Surface rivers and the use of groundwater is very little and also the extraction of gas, oil, and mining resources, which is another factor in the occurrence of land subsidence, does not exist in this area, and there isn’t also huge and heavy structure in the study area that affects the subsidence of the surface; so displacement in the study area is the result of active tectonics.

    Keywords: Morphotectonics, Coast, Caspian Plain, Radar Interferometry, Geodynamics
  • مجتبی یمانی*، ابوالقاسم گورابی، شیرین محمدخان، سید جواد حسینی

    استقرار رژیم تنشی معاصر در هر منطقه، نو زمین ساخت آن منطقه محسوب می شود. بررسی مورفولوژی حوضه ها با کمک نمایه های مختلف یکی از روش های برآورد وضعیت نوزمین ساخت آن منطقه می باشد که در دو دهه اخیر موردتوجه محققان بوده است. هدف این پژوهش، بررسی رابطه نو زمین ساخت و شکل حوضه های زنجان رود و مقایسه آن ها می باشد. زمین شناسی، توپوگرافی، لایه رقومی ارتفاع (DEM) دادهای پژوهش و نرم افزارهای GIS، WMS و Microsoft Ecxel نیز ابزارهای مفهومی پژوهش را تشکیل داده اند. نتایج نشان می دهد که بر اساس نمایه شکل حوضه (Bs)، 8 زیر حوضه با بالاترین ارقام در پهنه شمال غربی حوضه قرار داشته و حاکی از بالاترین سطح دخالت نوزمین ساخت این بخش از حوضه اصلی می باشد. قرار گرفتن 5 زیر حوضه با نمایه بالاتر از 4 در پهنه شمال غرب نیز می تواند تقویت کننده این فرضیه باشد. زیرا سطح فعالیت نوزمین ساختی در نیمه غربی نسبت به نیمه شرقی حوضه بالاتر است. این نتایج با پراکنش گسل های فعال منطقه نیز همخوانی دارد. در این میان، 18زیرحوضه با سطح پویایی پایین، در نیمه جنوب شرقی حوضه فراوانی بیشتری دارند. همچنین تحلیل ها نشان داد که ضلع جنوب شرقی ازنظر پویایی و دخالت زمین ساخت فعال در رده سوم قرار داشته و درنهایت ضلع شمال شرقی دارای پایین ترین سطح فعالیت نو زمین ساختی است. این پژوهش برای نخستین بار تمامی زیرحوضه-های زنجان رود را از منظر نو زمین ساخت و شکل حوضه ها موردبررسی قرار داده و مشخص کرد که شکل زیرحوضه ها در پهنه شمال غرب حوضه زنجان رود بیشتر متاثر از زمین ساخت بوده و از طرفی نمایه های مختلف همبستگی بالایی نداشته و به طور مجزا نتایج بهتری نشان می دهند.

    نتایج و بحث:

    در راستای اهداف تعیین شده برای مطالعه حاضر، ابتدا شکل زیرحوضه های موردمطالعه با استفاده از نمایه های مختلف کمی سازی شد. سپس وضعیت ظاهری زیرحوضه ها با استفاده از نمایه های مختلف شکل حوضه ارزیابی و در ادامه نمایه های مختلف شکل حوضه از نظر همخوانی در نتایج مربوط به زمین ساخت بررسی شدند. درنهایت نیز نو زمین ساخت زیرحوضه ها با بهره گیری از نتایج نمایه های شکل حوضه و اطلاعات مربوط به گسل های منطقه برآورد شده است. طبق ارقام به دست آمده نمایه ها، زیر حوضه کزبر دارای بیشترین حد کشیدگی است که به همراه 7 زیر حوضه با کشیدگی بسیار بالا در نیمه غربی حوضه زنجان رود تجمع یافته اند. از میان 18 زیر حوضه با نمایه شکل 2 تا 3، فراوانی زیرحوضه های این رده از نمایه شکل در نیمه جنوب شرقی حوضه بیشتر است. از تعداد 8 زیر حوضه با نمایه شکل کمتر از 2 در نیمه شرقی حوضه زنجان رود 1 زیر حوضه در پهنه شمالی و 7 زیر حوضه در پهنه جنوبی حوضه قرار دارند که در نیمه جنوب شرقی متمرکز شده اند. زیر حوضه موسوم به بالادست به دلیل پوشش سرشاخه های حوضه در مقیاس وسیع و نامتداول بودن شکل و در نتیجه قابل قیاس نبودن آن با سایر زیرحوضه ها، در طبقه بندی لحاظ نشده است.

    نتیجه گیری

    نتیجه حاصل از طبقه بندی نمایه ها نشان داد که تمرکز زیرحوضه های با کشیدگی و در نتیجه با تحرک نوزمین ساختی بالا در محدوده شمال غربی حوضه زنجان رود و به ویژه در پهنه شمالی این قسمت از حوضه است. این یافته تحقیق با آخرین نقشه تهیه شده از گسل های فعال منطقه همخوانی دارد که در آن تمرکز گسل های فرعی (ازجمله گسل سهرین، گسل قره چریان و گسل کناوند) در قسمت شمال غربی حوضه می باشد. طبق نتایج به دست آمده از بررسی شکل حوضه ها، ضلع جنوب غربی حوضه زنجان رود دارای سطح متوسط فعالیت نو زمین ساخت است که این یافته در کنار نتایج مربوط به قسمت شمال غربی می تواند تقویت کننده فرضیه فعال تر بودن نیمه غربی حوضه زنجان رود نسبت به نیمه شرقی آن باشد. ضلع جنوب شرقی حوضه نیز دارای سطح تحرک زمین ساختی متوسط بوده و نسبت به پهنه شمال شرقی حوضه تحرک نوزمین ساختی بالاتری دارد. همان طور که پژوهش های پیشین نیز نشان داده اند گسل های متعددی در مورفولوژی منطقه دخیل هستند.

    کلید واژگان: زنجان رود, زیر حوضه, نمایه شکل, نو زمین ساخت
    Mojtaba Yamani *, Abolghasem Gorabi, Shirin Mohammadkhan, Seyyed Javad Hosseini
    Introduction

    Rivers are very sensitive to changes in discharge and sediment load as well as tectonic forces. Many of the changes that occur over time in the morphology of the channel can be related to the mentioned changes. Morphometric analysis is the first step understanding the basin dynamic activity. Combined variables and indicators can be effective in identifying the complications and surface landform of river channels and show their temporal and spatial changes. In addition, in addition, geomorphological indices (Morphotectonic indices) are considered to be very useful methods in evaluating and recognizing tectonic activities and can provide quantitative results and quantitative description of morphometric features in The basin scale can be used to explain the structural controls, geological history and geomorphology and processes of its drainage network. In addition, the morphometric parameters of the basin play an important role in the hydrological processes governing the basin because it largely determines their hydrological response.

    Materials and Methods

    Zanjanrud is the main river basin completely limited to the area of ​​Zanjan province. The river originates from the heights of Soltanieh in the east and flows to the northwest and finally in the west of Rajein village it joins Qizil-Uzen. Regard to the objectives of the research, first, using the DEM of the basin (ASTER-DEM: 30m), the extractable sub-basins was identified in the WMS software environment. In this step the number of 107 sub-basins could be separated, of which 52 sub-basins were selected based on the minimum area of approx. 20 Km2 for the evaluation and analysis of shape indices and tectonic. These sub-basins were named according to the outstanding settlement inside them. After determining the shape indices and estimating and comparing the state of neotectonic of the sub-basins, a field survey was conducted to closely examine and validate the findings.

    Results and Discussion

    At the first, the shape of the studied sub-basins was quantified using different indices. Then, the morphology of the sub-basins was evaluated using different shape indices and then the different indices were checked in terms of correlation in terms of the results related to tectonic activity. Finally, the neotectonic of the sub-basins has been estimated using the results of the shape indices and the data related to the faults. The results show that the Kazbar sub-basin is most elongated sub-basin, which together with 7 sub-basins with very high elongation rate are located in the western half of the Zanjanrud basin.The frequency of sub-basins with the shape index 2 to 3 is in the SE half of the basin. Out of the 8 sub-basins with shape index less than 2 in the eastern half of Zanjanrud basin, 1 sub-basin is located in the northern part and 7 sub-basins are located in the southern part of the basin, which can be seen in the SE half. The upstream sub-basin is not included in the classification due to the unusual shape that cannot be compared with other sub-basins.

    Conclusion

    The results of classification of the indices shows that the accumulation of sub-basins with high rate of elongation and as a result with high neotectonic activity is in the NW part of Zanjanrud basin and especially in the northern side of this part.Out of the 51 sub-basins, the concentration of 8 sub-basins with mean index of higher than 5 and a total of 16 sub-basins with an average shape index higher than 3.5, indicates the highest level of neotectonic mobility in this part of the basin. This finding is consistent withthe region's latest map of active faults, in which the frequency of faults (including the Sohrein fault, the Qaracherian fault and the Kenavand fault) is in the NW part of the basin.According to the study results of the shape of the sub-basins, the SW side of the Zanjanrud basin has an average level of neotectonic activity. This finding, along with the results related to the NW part, can strengthen the hypothesis that the western half of the basin is more active than its eastern half. The neotectonic mobility in SE side of the basin is moderate and is higher than NE part of the basin. As previous studies have shown, many faults are involved in the morphology of the region.

    Keywords: Zanjanrud, Sub-Basin, Shape Index, Neotectonic
  • خدیجه محمدی، ابراهیم مقیمی، مهدی زارع، مجتبی یمانی*، مسعود مجرب

    منطقه بدخشان، در شمال شرق افغانستان دارای زمین شناسی پیچیده ای است. با استفاده از داده های کاتالوگ لرزه خیزی آسیای میانه با بروز رسانی (سال های 2011-1909) از سایت سازمان زمین شناسی آمریکا از سال 2011-2021 کاتالوگی تهیه گردید. با در نظر گرفتن آخرین زلزله با بزرگای 7.2 در سال 2015 ضرایب b به بیشترین مقدار 1.0 و a به مقدار 7.9 در سطح و عمق محاسبه گردید. افزایش مقادیر عددی a,b در نیمه مرکزی به طور کامل مشهود بوده است. نتایج حاکی از آن است روند حاضر، برخلاف راستای گسل اصلی شمال بدخشان (جهت شمالی- جنوبی) است. بیشترین فراوانی زلزله های ≥4 در عمق 70-150 کیلومتر، زلزله های ≥5 در عمق 300-150 کیلومتر و درنهایت زلزله های ≥6 در عمق 300-150 کیلومتر در راستای شرقی غربی رخ می دهد. این منطقه دقیقا برخورد صفحه دالان پامیر به مرکز بدخشان می باشد. این مهم نشان می دهد در منتهی الیه دالان پامیر از شرق به غرب گسیختگی هایی در عمق های 0-150 کیلومتر در حال ایجاد شدن هستند. دو روند شرقی-غربی و شرقی- جنوبی مشهود است. در خصوص زمین لرزه های کم عمق مربوط به 50 کیلومتر بالایی پوسته، سازوکار غالب از نوع نرمال است که حکایت از کشش پوسته در این بخش دارد. جهت نیروی کششی با توجه به سازوکار ژرفی زمین لرزه ها، در امتداد شرقی-غربی است. همین مسئله، موضوع برخورد قاره ای و سپس فرورانش به سمت جنوب بدخشان را بیشتر تایید می کند. نوآوری این پژوهش شناسایی روندهای لرزه ای است که در منطقه موردمطالعه به ندرت تحقیق شده است و کاربرد آن برای شناسایی نواحی پرخطر جهت ساخت وسازها می باشد.

    کلید واژگان: هندوکش, مورفوتکتونیک, بدخشان, افغانستان
    Khadijeh Mohammadi, Ebrahim Moghimi, Mehdi Zare, Mojtaba Yamani *, Masoud Mojarab

    Badakhshan region, located in the northeast of Afghanistan, has a complex geology. A catalog from 2011-2021 was prepared using the data of the Middle Asia seismic catalog with updates (1909-2011) from the website of the American Geological Survey. Considering the last earthquake with a magnitude of 7.2 in 2015, the coefficients of b were calculated to the maximum value of 1.0 and the value of 7.9 on the surface and in the depth, the increase in the numerical values of a and b in the central half has been completely evident. The results indicated that the current trend is opposite to the direction of the main fault in North Badakhshan (north-south direction). The most frequent earthquakes M≥4 occurs at a depth of 150-70 km, earthquakes M≥5 at a depth of 150-300 km, and earthquakes ≥6 at a depth of 150-300 km occur in the east-west direction. This area is exactly where the Pamir Corridor plate meets the center of Badakhshan. This shows that at the end of the Pamir Corridor from east to west, ruptures are being created at depths of 0-150 km. Two east-west and east-south trends are evident. Regarding the shallow earthquakes related to the upper 50 km of the crust, the dominant mechanism is of the normal type, which indicates the stretching of the crust in this section. According to the deep mechanism of earthquakes, the direction of the tensile force is in the east-west direction. This issue further confirms the issue of continental collision and then subduction towards the south of Badakhshan. The innovation of this research is the identification of seismic trends that have rarely been researched in the studied area, and its application is identifying high-risk areas for construction.

    Keywords: Hindu Kush, Morphotectonic, Fault, Badakhshan, Afghanistan
  • کاوه قهرمان*، مجتبی یمانی، بالاژ نایج

    سیلاب به عنوان یکی از مخرب ترین مخاطرات طبیعی در ایران و جهان، هرساله خسارات جانی و مالی زیادی بر جوامع وارد می آورد. بر همین اساس تعیین مناطق مستعد سیلاب می تواند نقش مهمی در کاهش خسارات ناشی از سیلاب های احتمالی در آینده ایفا کند. در این پژوهش، پهنه های سیل گیر در محدوده رودخانه کشکان با استفاده از مدل HAND تعیین شدند. به منظور تعیین پهنه های سیل گیر، از مدل رقومی ارتفاعی منطقه مورد مطالعه استفاده شد. همچنین از نرم افزارهای QGIS و Excel برای تهیه نقشه مناطق مستعد سیلاب و نیمرخ های ارتفاعی استفاده شد. در نهایت به منظور صحت سنجی نتایج مدل HAND، مناطق سیل زده در سیلاب فروردین ماه 1398 با استفاده از تصاویر راداری ماهواره سنتینل-1، نرم افزار SNAP و روش آستانه گذاری OTSU استخراج شدند و نقشه مناطق سیل زده در منطقه مورد مطالعه تهیه شد. نتایج این تحقیق نشان داد که تقریبا تمام مناطق شهری و روستایی در اطراف رودخانه کشکان در طبقه بسیار پرمخاطره و پرمخاطره قرار دارند. مقایسه نقشه HAND و مناطق سیل زده مستخرج از تصاویر راداری نشان داد که مدل HAND توانسته است با دقت بسیار بالایی پهنه های سیل گیر را تعیین کند. همچنین نتایج این پژوهش مشخص کرد که بخش های داخلی مئاندر در محدوده رودخانه کشکان جزو مناطق مهم مستعد سیلاب به شمار می روند. بر اساس نتایج، در رودخانه های مئاندری واقع در مناطق کوهستانی، محدودیت یا عدم محدودیت توپوگرافی نقش تعیین کننده ای در سیل خیزی بخش های بیرونی یا داخلی مئاندر دارد. این در حالی است که در رودخانه های مئاندری مستقر در دشت های سیلابی، به دلیل عدم وجود محدودیت توپوگرافی، بخش بیرونی مئاندر بیشتر از بخش داخلی آن مستعد سیل خیزی و غرق شدگی است.

    کلید واژگان: پهنه سیل گیر, سیلاب, کشکان, مدل HAND
    Kaveh Ghahraman*, Mojtaba Yamani, Balazs Nagy
    Introduction

    Floods pose significant risks as natural disasters on a global scale. In addition to climate change, anthropogenic activities have exacerbated the damaging effects of flooding over the past decade. Findings indicate that over 91 billion hectares of land in Iran are susceptible to flooding. Extensive hydrologic records reveal a total of 467 flooding events in the country up until 2002, contributing to a loss of 630 lives between 1982 and 1992. These alarming statistics underscore the necessity of studying and analyzing floods, as well as mapping inundation areas, in order to mitigate potential damage associated with future flooding events. One particular region in western Iran that has been heavily affected by recurring floods is the Kashkan River. This river traverses numerous urban and rural areas that are prone to annual flooding. Although various methodologies exist to investigate floods and identify areas susceptible to inundation, many of these approaches require data that may not be readily accessible. Consequently, this study employs the Height Above the Nearest Drainage (HAND) model to examine the flood-prone sections along the Kashkan River. Unlike other methods, the HAND model solely relies on a Digital Elevation Model (DEM), making it a promising and accurate technique for mapping inundation areas. By utilizing the HAND model, this research aims to identify specific sections of the Kashkan River that are prone to flooding. The findings of this study will contribute to a better understanding of flood dynamics in the region, enabling the development of effective strategies to minimize potential damage.

    Methodology

    In order to examine the areas that are prone to flooding, we employed the Height Above Nearest Drainage (HAND) model. This model was originally introduced by Rennó et al. (2008) and operates by utilizing a Digital Elevation Model (DEM) to compute the distance between a grid-cell within the topography data and the nearest cell along the stream it drains into. By considering cells with HAND values below a specific threshold as inundated, we can identify areas that are susceptible to flooding. Notably, the HAND model offers the advantage of being raster-based, eliminating the need for the construction of cross-sections, which is a requirement for alternative techniques like HEC-RAS. For our investigation, we employed the Shuttle Radar Topography Mission (SRTM) DEM, which possesses a resolution of 30 meters. To validate the findings obtained from the HAND model, we employed flood maps generated from Sentinel-1 Synthetic Aperture Radar (SAR) data from March 2019. These flood maps were created using the Sentinel Application Platform (SNAP) software and the OTSU thresholding method. This method allows us to distinguish flooded areas within the study region and validate the results obtained from the HAND model.

    Results

    The findings from this study indicate that a significant portion of the study area, encompassing 54.49 square km, is classified as highly flood prone. Additionally, an area measuring 31.78 square km is categorized as flood prone. Based on the HAND maps, it is evident that more than 30 percent of the study area is susceptible to flooding with varying intensities. The outcomes further reveal that the majority of both rural and urban regions situated alongside the Kashkan River are located within highly flood prone sections. Moreover, a comparison between the flood maps derived from Synthetic Aperture Radar (SAR) and the HAND results demonstrates that the HAND model successfully identified and classified the flood area in March 2019 as highly flood prone and flood prone. By examining the cross-section along the river, it becomes apparent that the inner banks of meanders are more susceptible to flooding when compared to the outer banks. Cross-section 1 analysis revealed that the sections with a high susceptibility to flooding are situated at higher elevations when compared to the maximum flood level observed in March 2019. This implies that in the event of more sever floods in the future, a larger portion of the areas along cross-section 1 will likely to be inundated. Additionally, the analysis demonstrated that during elevated flood flows, the outer bank of the meander is more prone to flooding compared to the inner bank. Similarly, in cross-section 2, the outer bank of the meander exhibits a greater extent of highly flood-prone areas compared to the inner bank. Furthermore, cross-section 2 findings indicate that the flood flow during March 2019 did not reach the upper limit of the highly flood-prone category. In contrast to the previous cross-sections, cross-sections 3 and 4 primarily experienced flooding along the inner bank of the meanders, and the HAND model also classified them as highly flood prone. These results suggest that the distribution of inundation in the Kashkan river is predominantly influenced by the underlying topography.

     Discussion & Conclusions

    The findings indicated that both rural and urban regions situated along the Kashkan river exhibit a high vulnerability to flooding, with a propensity for inundation during flooding events. The results revealed the efficacy of the HAND model in accurately identifying the flood-prone segments of the Kashkan River. Analysis of cross-sections along the river revealed that the inundation patterns in mountainous meandering rivers are predominantly influenced by the underlying topography. Overall, the HAND model represents a swift and precise approach for delineating areas at risk of flooding, thereby assisting authorities in enhancing planning strategies and implementing effective measures for mitigating damages.

    Keywords: Flood, HAND model, Kashkan, Flood-prone, Inundation
  • اسماعیل پاریزی، مجتبی یمانی*، سید رضا مهرنیا، مهران مقصودی، سید موسی حسینی

    فرسایش بادی و لندفرم های حاصل از آن چهره غالب دشت های هموار و پست مناطق خشک ایران است. شکل گیری پوشش گیاهی و نبکاها در بخش داخلی کویر درانجیر با وجود شوری و سخت شدگی زیاد رسوبات، سوال هایی را در مورد عوامل اصلی کنترل کننده آن ها مطرح می کند. روند خطی پوشش گیاهی و نبکاها و حرکت امتدادلغز گسل بافق - پشت بادام در این منطقه، فرضیه کنترل فرسایش بادی به علت وجود چشمه های آب شیرین گسلی را مطرح می کند. با توجه به اینکه در زمان حاضر فقط یک چشمه در امتداد گسل مذکور فعال است، یک نمونه 100 میلی لیتری از آب چشمه جهت آنالیز ژئوشیمیایی برداشت گردید. علاوه بر این، 4 گمانه در امتداد گسل (تا عمق 60 سانتیمتر) در منطقه رویش پوشش گیاهی و یک گمانه در رسوبات سخت شده کویر درانجیر (تا عمق 2 متر) حفاری و نمونه های رسوب و آب برداشت و سطح ایستابی در هر گمانه اندازه گیری شد. نتایج موید آن است که حرکت امتدادلغز گسل بافق- پشت بادام و به تبع آن ظهور چشمه های گسلی به سه شیوه متفاوت فرسایش بادی در منطقه موردمطالعه را تحت کنترل خود درآورده است: 1. با تشکیل یک زون مرطوب سبب رویش انواع مختلف پوشش گیاهی شده است و سرعت باد را در سطح کاهش داده، 2. با بالا آوردن سطح ایستابی در امتداد گسل مذکور و افزایش رطوبت سطحی مانع حمل ونقل رسوبات توسط باد شده است 3. با تشکیل نبکاها سبب تجمع رسوبات بادی در اطراف درختچه ها شده است.

    کلید واژگان: چشمه گسلی, فرسایش بادی, گسل بافق - پشت بادام, چاله درانجیر
    Esmail Parizi, Mojtaba Yamani *, Seiyed Reza Mehrnia, Mehran Maghsoudi, Seiyed Mossa Hosseini
    Introduction

    The wind erosion and the resulted landforms are the dominant landscape in flat and deep plains of Iran dry areas (Yamani, 2015). The importance of wind erosion in the deserts differs due to great variances in wind power (Goudie, 2013). This type of erosion which is controlled by the erosivity power of wind and the erodibility of impacted surfaces (sharma, 2010), is dangerous for three reasons: 1, the nutritious elements of the soil are destroyed and as a result the soil loses its power for keeping a conservative vegetation layer (Thomas, 2011). The deposition of eroded sediments can bury vegetation and river channels, pollute food and water reserves and also negatively impact the growth of vegetation, soil fertility, and the dynamics of ecosystem (Larney, 1998y; Worster, 2004; McTainsh & Strong, 2007 ). The transportation of eroded sediments through powerful winds can bring damage to buildings and products and also trouble visibility in roads and airports (Thomas, 2011).

    Materials and methods

    In first step, the impacted area of fault spring in Daranjir playa are identified based on satellite images, Geology maps and field observations. In the next step, 100 milliliter of water was sampled for chemistry analysis from active spring across Bafgh – Poshte-badam fault (Kor spring). Thus, to determine the water table, chemistry analysis of the sediment and water samples across Bafgh – Poshte-badam fault, 4 points were selected for drilling and the locations of bores were determined by GPS. To this end, the sampling procedure across the fault was conducted by a hand auger with the length of 20 cm and diameter of 7.5 cm. In sum, four water samples and 22 sediment samples were collected. In the geomorphology laboratory, initially the amounts of TDS, EC, and pH in the sample waters were measured by a multi parameter device, version HI9811-5. To measure the amounts of TDS, EC and pH in sand samples, saturated paste method was utilized. Here, the samples were initially dried in a drying device, and then 50 grams of each sample was measured with an accurate scale and mixed with 50 millimeters of distilled water. In the following step, the distilled water was mixed with sediment samples and the amounts of EC and TDS was measured using the multi parameter device and other devices.

    Discussion and Results

    The results suggest that the active tectonic performance across Bafgh-Posht badam fault not only result in the emergence of springs across the fault but also lead to the reduction of groundwater and the creation of a wet zone across the fault in Daranjir playa due to the penetration of water to the aquifer. This wet zone across the studied fault caused a significant growth of shrubs and Tamarix mascatensis, and reduced the speed of wind in the examined area. Regarding this Pye & Tsoar and state that in desert areas the salinity degree of groundwater has an important role in the transformation and distribution of deserts’ vegetation. The analyses of the qualitative and quantitative characteristics of groundwater across Bafgh- Posht badam fault show that the minimum water table, TDS and EC across the fault are ,respectively. In fact, by injecting fresh water across the fault, the fault springs not only reduce the salinity of groundwater but also raise the the water table across the mentioned fault and bring the transportation of the sediments to a minimum level. As for this case, Silva et al., (2018) state that in areas with high water tables, the sand sources are limited and consequently the transportation of sediments reduces. Moreover, Kocurek & Nielson concluded that high water tables can reduce the transportable sediment by conserving surface moisture. In addition to the formation of vegetation, the increase of water level across the fault, the creation and change of Nebkha formation location are the main effects of spring faults which have a crucial role in controlling wind sediments. As a matter of fact, the fresh water of springs results in the formation of vegetation and this vegetation captures wind sediments and forms Nebkhas.

    Conclusion

    The results of this study show the strike-slip movement of Bafgh – Poshte-badam fault and the emergence of fault springs have a key role in controlling wind erosion and formation of eaolian landforms in Dar-Anjir playa. Indeed, the fault springs control the wind erosion in the present case study in three ways: 1: the formation of wet zone creates various types of vegetation and reduces wind speed in surface, 2: the raising of water table across Bafgh – Poshte-badam fault and the increase of the moisture surface impede the movement of sediment by wind and 3: With formation of nebkhas causes the aeoilan sediment accumulation around Shrubs.

    Keywords: Fault Spring, Wind Erosion, Bafgh – Poshte-Badam Fault, Daranjir Playa
  • مهین پیره*، مجتبی یمانی

    عوامل محیطی نقش اصلی را در پراکنش و نحوه استقرار نواحی سکونتگاهی در طول تاریخ داشته اند و با بررسی شرایط محیطی هر منطقه می توان تا حدود زیادی به وجود نواحی سکونتگاهی باستانی در آن منطقه پی برد. با توجه به اهمیت بررسی نحوه پراکنش سکونتگاه های باستانی، در این پژوهش به تحلیل عوامل محیطی در نحوه استقرار سکونتگاه های باستانی در شهرستان پیرانشهر پرداخته شده است. در این پژوهش از مدل رقومی ارتفاعی 30 متر، لایه سایت های باستانی شناسایی شده در منطقه، نقشه 1:100000 زمین شناسی و نقشه 1:50000 توپوگرافی منطقه به عنوان داده های تحقیق استفاده شده است. مهم ترین ابزار مورد استفاده در تحقیق ArcGIS بوده است و همچنین در این تحقیق از مدل تلفیقی منطق فازی و AHP نیز استفاده شده است. این تحقیق به صورت کلی در دو مرحله انجام شده در مرحله اول به تحلیل پراکنش سایت های باستانی در ارتباط با عوامل مختلف محیطی پرداخته شده و در مرحله دوم نیز مناطق مستعد استقرار سکونتگاه های باستانی شناسایی شده است. بر اساس نتایج حاصله، پراکنش سایت-های باستانی در ارتباط مستقیم با شرایط محیطی بوده است به طوری که بیش ترین میزان تراکم سایت-های باستانی در مناطق با شیب کم، مناطق کم ارتفاع، مناطق نزدیک به رودخانه، جهات شیب شمالی، واحد آبرفت های کواترنری و همچنین واحد دشت های آبرفتی بوده است. مجموع نتایج حاصله از این پژوهش نشان داده است که شرایط محیطی در گذشته نیز نقش اصلی را در پراکنش نواحی سکونتگاهی داشته است و با بررسی شرایط محیطی هر منطقه تا حدود زیادی می توان به وجود سایت های باستانی در آن منطقه پی برد

    کلید واژگان: عوامل محیطی, سکونتگاه هایی باستانی, پراکنش مکانی, پیرانشهر
    Mahin Pireh *, Mojtaba Yamani
    Introduction

    How the first human settlements came to be is an important issue, and from different scientific perspectives, different answers can be given; because the creation or degeneration of these settlements is not the choice of individuals; it depends on countless human and natural conditions. Studies show that the establishment of human societies on the ground has always been done in order to achieve maximum natural resources such as water resources, adequate vegetation and access to arable land, this effort is undoubtedly based on the principles that today It is interpreted as the science of location. At the beginning of human life, natural hazards were unknown to humans until their occurrence. Natural are also safe. Natural disasters are born of natural elements and factors, but human profiteering intervention in nature affects the quantity and quality of many natural disasters. Considering the mentioned cases, environmental factors, especially geomorphology, have played an important role in locating residential areas throughout history. Accordingly, in this study, environmental factors affecting the distribution of ancient settlements in Piranshahr have been investigated.

    Materials and methods

    In this research, in order to achieve the desired goals, a 30-meter-high digital model, a layer of ancient sites identified in the region (Masoumian, 2021), a 1: 100000 geological map and a 1: 50,000 topographic map of the region have been used. The most important tool used in the research was ArcGIS and also in this research the combined model of fuzzy logic and AHP has been used. This research has generally been done in two stages. In the first stage, after preparing the layer of ancient sites in the region, the location of ancient sites in terms of slope, slope classes, elevation classes, distance classes from the river, lithology units and geomorphological units are analyzed and thus the distribution status of sites Ancient has been analyzed in relation to environmental conditions. In the second stage, in order to identify areas prone to ancient settlements, the results of the previous stage have been used and using the integrated model of AHP fuzzy areas, a map of areas prone to ancient settlements has been prepared.

    Discussion and results

    In this study, in order to investigate the effects of environmental conditions on the distribution of ancient settlements, first the location of 67 ancient sites in Piranshahr city has been determined. According to the results, a large part of the ancient settlements are located in the slope classes less than 10%, so that 32 ancient sites (equivalent to 47.8% of the identified sites) are located in this class. In terms of slope, a large part of the ancient settlements are located in the northern directions so that 36 ancient sites (38.8% of the identified sites) are located in the northwest to northeast. In terms of height, a large part of the ancient sites are located in the altitude classes of 1250 to 1650, so that in this category there are 56 ancient sites (equivalent to 83.6% of the identified sites). In terms of distance from the river, a large part of the ancient sites are located near the river, with 48 ancient sites (equivalent to 71.6% of the identified sites), located less than 500 meters from the river. They had. Lithologically, a large part of the settlements are located on Quaternary alluvial sediments, so that 37 ancient sites (equivalent to 55.2% of the identified sites) are located in this unit. Also, in terms of geomorphology, a large part of the ancient sites are located in the alluvial plain unit, so that 37 ancient sites (equivalent to 55.2% of the identified sites) are located in this unit.

    Conclusion

    Environmental conditions have played an important role in the settlement of residential areas in the past and today. Considering that the knowledge of the effective factors in location selection has an important role in various planning, in this study, the effective environmental factors in the establishment of ancient sites in Piranshahr city have been analyzed. Based on the results, the distribution of ancient sites was directly related to environmental conditions, so that the highest density of ancient sites in low-slope areas, low-lying areas, areas near the river, north slope directions, unit Quaternary alluvium as well as unit of alluvial plains. According to the results obtained at this stage, areas prone to the establishment of ancient settlements in Piranshahr city have been identified that based on the results, the middle areas of Piranshahr city due to the conditions, are prone to the development of ancient settlements. The results of this study have shown that environmental conditions in the past have played a major role in the distribution of residential areas and by examining the environmental conditions of each area to a large extent can be found the existence of ancient sites in that area.

    Keywords: Environmental Factors, Ancient settlements, spatial distribution, Piranshahr
  • علی عبدی نژاد، مجتبی یمانی، جعفر حسن پور*، ابوالقاسم گورابی، مصطفی کریمی احمد آباد

    در این مطالعه، به بررسی پتانسیل وقوع زمین لغزش های کم عمق ناشی از بارندگی در حوضه آبریز سجادرود پرداخته شده است. در این حوضه به دلیل توپوگرافی کوهستانی (شیب تند دامنه ها) و وجود خاک های حاوی مواد آلی به صورت طبیعی پتانسیل رخداد اینگونه زمین لغزش های ناشی از بارندگی زیاد است و سالانه زمین لغزش هایی با ابعاد مختلف بعد از وقوع بارندگی های شدید و طولانی مدت در آن رخ می دهد. این زمین لغزش ها که با مکانیسم لغزش در بخش های بالایی پوشش خاک آغاز می شوند، بلافاصله تبدیل به جریان های گلی-واریزه ای شده و از به هم پیوستن آنها ممکن است جریان های واریزه ای-گلی بزرگ در پایین دست حوضه شکل بگیرد که پدیده ای مخرب محسوب می شود. در این پژوهش، برای بررسی تاثیر بارندگی بر وقوع زمین لغزش های کم عمق و جریان های واریزه ای-گلی از برنامه تریگرز (TRIGRS) که برنامه ای نسبتا جامع و مبتنی بر شبکه برای تحلیل پایداری شیب به روش شیب بی نهایت (در مقیاس ناحیه ای) است، استفاده شده است. در این برنامه اثر نفوذ آب باران در خاک و رواناب ناشی از بارندگی که پارامترهایی مهم در ایجاد زمین لغزش های کم عمق و متعاقب آن جریان های واریزه ای-گلی هستند نیز به طور کامل در نظر گرفته می شود و این پدیده طبیعی به طور کامل شبیه سازی می گردد. داده های ورودی مورد نیاز برای این پژوهش شامل داده های توپوگرافی حوضه، ویژگی های زمین شناسی، زمین شناسی مهندسی و هیدروژیولوژیکی واحدهای خاکی (زون های زمین شناسی) و داده های مربوط به بارش در منطقه است که از منابع مختلف تهیه و در قالب فایل های متنی و نقشه های GIS مناسب مرتب سازی شده و مورد استفاده قرار گرفته اند. خروجی برنامه تریگرز شامل نقشه های توزیع مکانی حداقل ضریب ایمنی پایداری، عمق وقوع لغزش و فشار آب منفذی در عمق وقوع لغزش هستند که در قالب فایل های متنی تهیه و بعد از ترسیم در نرم افزارهای مبتنی بر GIS قابل تفسیر هستند. نتایج این مطالعه نشان داد که در بخش های مرتفع و پرشیب حوضه هرجا که خاک هایی با سنگ بستر از جنس سنگ های غنی از کانی های رسی (مثل گلسنگ، مارن و شیل) گسترش بیشتری دارند، پتانسیل رخداد لغزش های کم عمق ناشی از بارندگی بالاست و با وقوع بارندگی های با شدت بالا و مدت طولانی، این نوع زمین لغزش ها رخ خواهند داد که در صورت نزدیکی به سکونتگاه ها و جاده ها می توانند ریسک بالایی برای آنها داشته باشند. در بررسی های صحرایی صورت گرفته، همخوانی خوبی میان نتایج این مطالعه با تجربیات حاصل از مشاهدات صحرایی زمین لغزش های ناشی از بارندگی در منطقه از نظر توزیع مکانی و زمان وقوع آنها به دست آمد.

    کلید واژگان: زمین لغزش کم عمق, فشار آب منفذی, زمین لغزش ناشی از بارندگی
    Ali Abdinezhad, Mojtaba Yamani, Jafar Hassanpour*, Abolghasem Goorabi, Mostafa Karimi Ahmadabad

    In this study, the occurrence potential of rainfall-induced shallow landslides in the Babolrood basin has been investigated. In this basin, due to the mountainous topography and the presence of loose organic soils, the potential of such landslides is high, and landslides of different sizes occur every year after long and intense rainfalls. These landslides, which start with the sliding mechanism in the upper parts of the soil cover, immediately turn into earth/debris flows, and from their joining together, large flows may form downstream of the basin, which is considered a destructive phenomenon. In this research, to investigate the effect of rainfall on the occurrence of shallow landslides and flows, the TRIGRS program, which is a comprehensive and grid-based program for slope stability analysis using the infinite slope method, has been used. In this program, the effect of rainwater penetration into the soil and runoff caused by rainfall, which are important parameters in the occurrence of shallow landslides and subsequent flows, are also fully considered and this natural phenomenon is fully simulated. The input data required for this research includes topographical data of the basin, geological and hydrogeological properties of soil units, and rainfall data in the region, which are prepared in the form of appropriate text files and GIS maps. The output of the Triggers program includes maps of the spatial distribution of the minimum safety factor, the depth of the failure, and the pore water pressure at the failure depth, which are prepared in the form of text files and can be interpreted in GIS-based software. The results of this study showed that in the high and steep parts of the basin, wherever there are soils on a bedrock rich in clay minerals (such as mudstone, marl, and shale), the potential for shallow rainfall-induced landslides is high. In the field studies, a good agreement between the results of this study and the experiences obtained from field observations of landslides caused by rainfall in the region was obtained in terms of their spatial distribution and time of occurrence.

    Keywords: Shallow landslide, Pore pressure, Rainfall-induced landslide
  • مجتبی یمانی*، شهناز جودکی

    پادگانه ها آرشیوهای مهمی برای دیرینه شناسی به شمار می روند. در این پژوهش، تغییرات دمای دیرینه و تناوب دبی حوضه جاجرود در شمال شرق تهران بر اساس ویژگی های رسوب شناسی و ژیوشیمی پادگانه ها بررسی شده است. ابتدا با تکنیک های کلسیمتری، EC، XRF و PH نمونه های رسوبی آنالیز و سپس این داده ها با اندیس های میزان شوری، هوازدگی شیمیایی، اسیدیته و بلوغ لایه های رسوبی پادگانه ها ارتباط داده شده اند. نتایج نمایانگر سه دوره تغییرات دبی، طی تناوب دوره های سرد و گرم رود داده است. یکی در اوج دوره یخچالی که انباشت برف و یخ در بخش کوهستانی کاهش دبی را به همراه داشته است (قبل از هولوسن). در مرحله دوم، با گذر از دوره یخچالی به گرم (11 تا 8 هزار سال قبل) جاجرود بیشترین دبی خود را تجربه کرده است. زیرا ذوب یخچال ها با دبی بارش توام بوده است. وجود لایه بندی بسیار درشت بافت در پادگانه های اوایل هولوسن نشانگر وقوع سیلابهای در این دوره است. در مرحله سوم، تسلط شرایط گرم و خشک اخیر(8 هزار سال پیش تاکنون) و فقدان ذخایر یخچالی، منجر به کاهش دبی رودها شده است. زیرا امروزه دبی جاجرود صرفا از بارش تامین می شود و وقوع سیلاب های دوره ای نیز نتیجه مستقیم خروج از آستانه های شدت و مدت بارش ها است. بر این اساس، مطالعات ژیوشیمی پادگانه ها می تواند داده های ارزشمندی را برای بازیابی تغییرات دینامیکی جریان و دبی، طی دوره کواترنری فراهم کرده و قابل تعمیم به سایر حوضه های مشابه است.

    کلید واژگان: دبی دیرینه, ژئوشیمی رسوبی, پادگانه, کواترنری, حوضه جاجرود
    Mojtaba Yamani *, Shahnaz Joudaki

    Terraces are important archives for paleontology. In this research, the paleotemperature changes and discharge frequency of Jajroud basin in the northeast of Tehran have been investigated based on the sedimentology and geochemistry characteristics of the reservoirs. First, the sediment samples were analyzed with calcimetry, EC, XRF, and PH techniques, and then these data were correlated with the indices of salinity, chemical weathering, acidity, and maturity of the sedimentary layers of the defenses. The results show three periods of flow changes, during the alternation of cold and warm periods of the river. One is at the peak of the glacial period, when the accumulation of snow and ice in the mountainous part has reduced the discharge (before the Holocene). In the second stage, by passing from the glacial period to the warm period (11 to 8 thousand years ago), Jajrud has experienced its highest discharge. Because the melting of glaciers has been accompanied by rainfall. The existence of very coarse layering in the early Holocene terraces indicates the occurrence of floods in this period. In the third stage, the dominance of recent hot and dry conditions (8 thousand years ago until now) and the lack of glacial deposits have led to a decrease in river flow. Based on this, the geochemical studies of the reservoirs can provide valuable data to recover the dynamic changes of flow and discharge during the Quaternary period and can be generalized to other similar basins.

    Keywords: Paleo-discharge, Sedimentary Geochemistry, Terrace, Quaternary, Jajroud Basin
  • Afsaneh Ehdaei, Mehran Maghsoudi *, Seyed Mohammad Zamanzadeh, Mojtaba Yamani
    The presence of water resources, particularly rivers, significantly influences site selection. Throughout history, settling near rivers has brought numerous advantages, but it has also posed certain risks. This study focuses on the sub-basins southeast of the Caspian Sea. Initially, we explore the connection between the layout of ancient settlements and the drainage networks. Additionally, we analyze the relationship between flood risk and the settlement patterns of these ancient sites by estimating the flooding risk based on linear, areal, and relief aspects. This research marks the first time such an analysis has been conducted. The findings underscore the importance of proximity to rivers in site selection, with areas close to rivers with lower stream orders being the most favorable for settlements. The study reveals a decrease in the frequency of sites near higher stream orders in relation to flooding risk. Conversely, there is an increase in the frequency and density of ancient sites near the first stream orders and at greater distances from the rivers, coinciding with an elevated flooding risk in the sub-basins. These results indicate that the inhabitants of the southeastern areas of the Caspian Sea sub-basins were cognizant of the flooding danger and factored it into their decision-making when selecting settlement sites
    Keywords: Geoarchaeology, Settlement Pattern, hydro geomorphology, Flood, Southeastern of the Caspian Sea
  • شهناز علیزاده، مجتبی یمانی*، محمدرضا ثروتی، منیژه قهرودی

    بی توجهی نسبت به فرسایش ساحلی موجب وقوع مخاطره می شود. این مخاطره به طور مستقیم و غیرمستقیم بر جوامع انسانی و تاسیسات ساحلی تاثیرگذار است. پژوهش های دیرینه شناسی موید افت وخیز تراز آبی دریای خزر در قالب ارقام متفاوتی تا چند ده متر است. سواحل دریای خزر دارای توپوگرافی و کاربری اراضی متفاوتی ازجمله اراضی پست مرتبط با مصب رودخانه ها، خورها و یا پیشرفتگی های آب دریا در خشکی و سواحل نسبتا بلندتر ماسه ای و شنی است. در این پژوهش با استفاده از تحلیل زمانی - مکانی تغییرات کاربری اراضی در طول 45 سال به تحلیل تغییرات ساحل ماسه ای و انطباق آن در ساحل موردمطالعه در قالب سلول های ساحلی پرداخته شده است. برای این منظور با استفاده از نرم افزارهای SAGA و ENVI داده های کاربری اراضی سال های 1975 و 2020 و سپس با نرم افزار IDRISI تغییرات کاربری اراضی استخراج شدند. نتیجه پژوهش حاکی از آن است که 9 /68 کیلومتر از بازه ساحلی موردمطالعه، سواحل ناپایداری بوده اند که بیشترین نواحی ساحلی فرسایش از نوع انسانی (تغییرات کاربری اراضی) داشته اند، که شامل سلول های 10 و 3 می باشند. همچنین فرسایش سلول های ناپایدار 5، 6 و 1 از نوع فرسایش طبیعی (تغییرات ایوستاتیک دریا) و فرسایش سلول های ناپایدار 9 و 2 از نوع فرسایش طبیعی - انسانی می باشند. 24 کیلومتر باقیمانده بازه ساحلی موردمطالعه، سواحل پایداری بوده اند. در این میان، بیشترین بخش های ساحلی، فرسایش از نوع طبیعی (تغییرات ایوستاتیک دریا) داشته اند. این بخش ها عمدتا دو سلول 7 و 8 را دربر می گیرند. همین طور سلول 4 نیز در گروه سواحل پایدار با فرسایش از نوع طبیعی - انسانی قرار می گیرد.

    کلید واژگان: پایداری ساحلی, سلول ساحلی, انطباق خط ساحلی, کرانه غربی خزر
    Shahnaz Alizadeh, Mojtaba Yamani *, MohammadReza Sarvati, Manijeh Ghahroudi Tali

    Neglecting coastal erosion can lead to environmental hazards that are among the main factors affecting human communities and facilities. Paleontology researches demonstrate tens of meters fluctuation in water level of the Caspian Sea. The shores of the Caspian Sea have variable topography and land use including lowlands (estuaries of rivers, gulfs and progradation) and sandy uplands. In this study, spatiotemporal analysis was used to analyze the changes in sandy coasts in relation to land use changes and the adaptation of the coastal line in the study area within the framework of coastal cells. Land use data for the years 1975 and 2020 were extracted using SAGA and ENVI software, and land use changes were analyzed using IDRISI software. The results showed that 68 kilometers of the coast have been unstable, with the majority of these areas experiencing erosion due to human activities (land use changes), including cells 10 and 3. Also, the erosion of unstable cells 5, 6, and 1 is of natural erosion type (sea level changes), and the erosion of unstable cells 9 and 2 is of natural-human erosion type. The remaining 24 kilometers of the studied coastline have been stable coasts, with the majority of coastal areas experiencing natural erosion (sea level changes), including cells 7 and 8. Cell 4 has had sustainable coasts with erosion of a natural-human type.

    Keywords: Coastal Sustainability, Coastal Cell, managed relocation, the west bank of the Caspian Sea
  • سیاوش شایان*، مجتبی یمانی، امین عبدالعلی پور عدل، نازفر آقازاده

    حوضه گیوی چای در جنوب استان اردبیل با مساحت 1554 کیلومتر مربع، از زیر حوضه های درجه سه سفیدرود است که این خطر هر از چندی در آن رخ می دهد؛ به همین منظور، پهنه بندی سیل خیزی حوضه گیوی چای همواره قابل توجه است. پس از تهیه نقشه پهنه بندی، حوضه مورد مطالعه بر اساس شدت سیل خیزی به پنج کلاس بسیار کم، کم، متوسط، زیاد و بسیار زیاد تقسیم بندی شد. همچنین نقشه نهایی سیل خیزی حوضه با روستاهایی که در سال های اخیر به سبب سیل آسیب دیده اند، اعتبارسنجی شد. بیشترین مساحت مناطقی که در پهنه های با خطر بسیار بودند، شیب و بارش های زیاد داشتند و از لحاظ لیتولوژی و هیدرولوژی خاک نیز دارای نفوذپذیری بسیار پایینی بودند و در مناطقی که پوشش گیاهی کمتر و ضعیف است، همپوشانی داشت و بیشتر در معرض سیلاب ها بود. برای پهنه بندی سیل خیزی از داده های ارتفاع، شیب، لیتولوژی، بارش، پوشش گیاهی، هیدرولوژی خاک، فاصله از رودخانه، تراکم زهکشی و کاربری اراضی استفاده شد. لایه های خاک، لیتولوژی و کاربری اراضی با استفاده از نرم افزار IDRISI و بقیه لایه های مورداستفاده با استفاده از ابزار fuzzy membership فازی سازی و تمام لایه ها در نرم افزار Expert Choice وزن دهی شد. تحلیل و مدل سازی نهایی نیز با استفاده از مدل FAHP فازی گاما انجام شد. نتایج نشان داد که تراکم زهکشی، بیشترین تاثیر و پوشش گیاهی، کمترین تاثیر را در سیل خیزی داشت. با توجه به همبستگی بالای گاما 9/0 با معیارهای سیل خیزی، نقشه نهایی انتخاب شد. بر این اساس، قسمت های مرکزی حوضه دارای ارتفاع بالاتری بود و نسبت به مناطق پست تر قسمت های غربی، توان بالایی برای سیل خیزی داشت.

    کلید واژگان: استان اردبیل, پهنه بندی, سیل خیزی, رودخانه گیوی چای, مدل فازی
    Siavosh Shayan*, Mojtaba Yamani, Amin Abdolalipour Adl, Nazfar Aghazadeh
    Introduction

    The natural hazards are impossible to avoid, and infrastructure elements and communities cannot be made totally invulnerable. The only viable solution is the complex risk analysis and subsequent development of combination of mitigation and adaptation strategies Floods are the most common natural disaster type worldwide. Between 1995 and 2015, 2.3 billion people were affected by floods, con siderably more than any other type of natural disaster event. In general, the Givi Chai basin includes two cities, Khalkhal and Kausar. In recent years, floods have caused damage to gardens and facilities due to spring and summer rains to the extent that the villages that are located under the Sangur Chai basin because of being located at the source of the rivers and mainly in the course of the rivers are affected by floods; also in the whole basin due to droughts and the destruction of vegetation and the increase of man-made areas, the amount of impermeability has increased. Considering that Khalkhal is a mountainous area and is one of the areas sensitive to landslides in Azariaijan region, heavy rainfall and floods can wash away the slopes of this area.

    Methodology

    The Givi Chai basin in the south of Ardabil province with an area of 1554 square kilometers is one of the 3rd degree basins of Sefidroud, which is located in the geographical coordinates of 48°4' E longitude to 48°38' E longitude 37°27' N latitude 37°55' N latitude. In order to achieve the goals of this research, firstly, the theoretical foundations and the works done in connection with flood zoning of basins in Iran and outside Iran were examined. Many variables are effective in the flood of basins. In this research, from the 1.100000 geological map, the slope maps were obtained using the digital height model map; the land use map was obtained through the classification of the  Maximum Likelihood  in ENVI software. In addition, using the digital model of the height of resolution  to extract, a drainage density map was prepared using the Line density tool. In this research, using the FAHP fuzzy hierarchical analysis model, Expert CHOISE software was used for weighting the layers, and finally, a map was prepared in the Arc GIS environment using gamma 0.5, 0.7 and 0.9The basin was flooded.

    Results

    After preparing the effective factors for zoning the flood potential of the basin, the gamma fuzzy operators of 0.5, 0.7 and 0.9 were used. 37 floods have occurred in the studied basin from 1365 to 1399 in different parts and villages, which caused the destruction of rural houses, gardens, agricultural lands and livestock. In order to determine the final flood map, points were randomly selected on the zoning map, then the correlation level was obtained based on the specified points with each of the criteria in the ARC GIS software. Based on the results obtained from the correlation, the highest correlation level is related to gamma 0.9. Vegetation has the highest correlation of 0.5 and lithology has the lowest correlation with gamma of 0.9 and 0.062. Also, the last flood occurred in the studied basin in the villages of Mustafa Lo, Bolokan, Morestan and Khoda Qeshlagi, which are located in the high-risk zone according to the final flood zoning map.

     Discussion & Conclusions

    In this research, using the FAHP model, flood potential zoning has been evaluated in Givi Chai basin. The data of height, slope, lithology, precipitation, vegetation, soil hydrology, distance from the river, drainage density and land use have been used for flood zoning. After preparing the zoning map, the studied basin was divided into five classes based on the severity of flooding: very low, low, medium, high, very high. The results obtained from the flood zoning of Givi Chai basin have shown that the largest area of the studied basin, which is 0.9 gamma scale, has the highest correlation. The strata with very low, low and medium potential, gamma 0.5  0.7, were showed. cover the area of Givi Chai basin. Also, the final flood map of the basin was validated with the villages that have been damaged by floods in recent years. The areas which are more exposed to floods are in the regions that have very low permeability in terms of lithology and hydrology of the soil and in the areas where the vegetation cover as less as.

    Keywords: Ardabil province, Assessment, Zoning, flooding, Givi chaie River, fuzzy model
  • حمید گنجائیان، مجتبی یمانی*، ابوالقاسم گورابی، مهران مقصودی

    امروزه مخاطرات ناشی از جابجایی زمین نقش اساسی در مدیریت محیط طبیعی و جوامع انسانی دارد. تحقیق حاضر با استفاده از روش تداخل سنجی راداری به ارزیابی میزان جابجایی عمودی زمین در یکی از مهم ترین دشت های ایران (کرمانشاه) و تاثیر زلزله بزرگ 21/08/1396 ازگله پرداخته است. در این راستا از تصاویر سنتینل-1 مربوط به سه بازه زمانی 24/11/2016 تا 07/11/2017 (قبل از زلزله) و 07/11/2017 تا 19/11/2017 (قبل و بعد از زلزله) و همچنین 24/11/2016 تا 19/11/2017 (بعد از زلزله) استفاده شده اند. در این تحقیق ابتدا میزان جابجایی بازه زمانی اول با استفاده از روش سری زمانی SBAS (13 تصویر) محاسبه شده است. سپس با استفاده از 2 تصویر قبل و بعد از زلزله، میزان تغییرات ناشی از زلزله ارزیابی شده است و در نهایت با استفاده از روش سری زمانی SBAS (14 تصویر) میزان تغییرات بازه زمانی سوم محاسبه شده است. نتایج ارزیابی ها بیانگر است که محدوده مطالعاتی در بازه زمانی اول بین 107+ تا 40- میلی متر، در بازه زمانی دوم (قبل و بعد از زلزله) بین 22+ تا 46- میلی متر و در بازه زمانی سوم بین 102+ تا 33- جابجایی داشته است. با توجه به میزان بالاآمدگی قابل توجه محدوده مطالعاتی در طی دوره زمانی مورد مطالعه، پیشنهاد می گردد که در بررسی میزان جابجایی عمودی هر منطقه باید نقش عوامل تکتونیکی، از جمله زلزله ها را مورد توجه قرار دارد.

    کلید واژگان: دشت کرمانشاه, تداخل سنجی راداری, نوزمینساخت, زلزله ازگله, SBAS
    Hamid Ganjaeian, Mojtaba Yamani *, Abolghasem Goorabi, Mehran Maghsoudi
    Introduction

    The shape of the earth changes over time and these changes can be periodic or non-periodic. Land deformation may be related to tectonic processes such as earthquakes, faults, volcanoes, landslides, and anthropogenic processes such as mine activity and groundwater exploitation. Subsidence and uplift is one of the most important changes in the shape of the earth. Which is directly related to the tectonic status of the areas. Which is directly related to the tectonic status of the areas. The land of Iran as part of the active alpine-Himalayan tectonic zone has been affected by numerous tectonic activities over time, with the emergence of the Zagros-Makran and Alborz-Kope-Dagh mountains in the Iranian plateau due to the Arabian-Indian Plateau drifting from the landforms resulting from this convergence. Kermanshah plain is also active in tectonic terms due to its location in folded Zagros, therefore it has a lot of potential for the displacement of the Earth's surface. Today, the calculation of ground-level displacements using radar interference technology includes unique capabilities in terms of dimensions, cost, time and accuracy compared to other measurement techniques. Accordingly, in the present study, radar interferometry method was used to assess the amount of subsidence and uplift of Kermanshah Plain and the correlation of this displacement with the earthquake in Kermanshah on 21/08/1396.

    Materials and Methods

    Nowadays, calculation of displacements occurring on the surface using radar interferometry technology has unique capabilities in terms of size, cost, time and accuracy compared to other measurement techniques. Therefore, in the present study, using radar interferometry method and SBAS time series, the vertical displacement rate of Kermanshah plain and its relationship with 7.3 earthquake of Kermanshah Ezgele have been investigated. In this study, the displacement rate was calculated for three periods:-the first time in the history of 11.24.2016 to 11.07.2017 and includes 13 image Sentinel 1.Second period is from the date of 07/11/2017 to 11/19/2017 (before and after the earthquake). The third time frame selected to assess the impact of the earthquake on the process of changes and calculations for different purposes is from 24/11/2016 to 19/11/2017 (including 2 images).

    Discussion and results

    The results show that the Kermanshah herd earthquake has a direct role in the vertical displacement of Kermanshah plain. The result of calculating the vertical displacement in the first period indicates that the northwest and southeast areas of Kermanshah urban area have subsided and the northeast and southwest elevations have been elevated, but this trend has changed due to the earthquake of the Ezgele, So that the earthquake of the Ezgele has increased many parts of the study area, especially its southern regions, and has also subsided in the northeast areas of the study area, so the results in the third time period have been very variable, It is concluded that the Kermanshah northeast highlands, which had been uplifted during the first period, were associated with a subsidence due to the Kermanshah herd earthquake. Also the southeastern areas of Kermanshah urban area which had subsided in the first period, Due to the direct impact of the earthquake from the Ezgele, it has been experiencing an uplift in the third period. Therefore, it can be said that the earthquake of the Ezgele, while changing the vertical displacement process of Kermanshah plain, can affect the results of different calculations in this regard.

    Conclusion

    In this research, in order to investigate the factors affecting this displacement, three time intervals were used to evaluate the vertical displacement of the area. The results indicate that the range of studies ranged from +107 to -40 mm. Given that the amount of positive displacement (uplift) was higher than the negative displacement (subsidence) and also the tectonic factors, the main cause of the displacement can be attributed to the tectonic factors, however, other factors such as groundwater depletion can affect the rate of subsidence in the northwest and southeast of Kermanshah urban area. Evaluation results in the second time period indicate that the study area had a vertical displacement of between +22 to -46 mm during the 12 day period before and after the earthquake, which could be attributed to the short-term period. Directly attributed to the earthquake of the Ezgele. The third study period also had a range of displacements of +102 to +33 mm, but the important and significant point in this period was the impact of the earthquake of the herd on the extent and trend of displacement in the study area. In fact, the results show that in the first period, the northwest and southeast areas of Kermanshah metropolitan area have subsided and the northeast and southwest areas have risen, while the northeast Kermanshah highlands have subsided. The first time has been uplift, during this period has been associated with subsidence due to the Kermanshah Ezgele earthquake. Also, the south-eastern areas of Kermanshah metropolitan area which had subsided in the first period, due to the direct impact of the earthquake from the Ezgele, in the third period has been rising. Therefore, it can be said that the earthquake in Kermanshah plain, while changing the vertical displacement process, can affect the results of different calculations in this regard.

    Keywords: Kermanshah Plain, Nontectonic, Ezgeleh earthquake, SBAS
  • مهدی امینی، موسی حسینی*، شیرین محمدخان، ابراهیم مقیمی، مجتبی یمانی

    ساختار مدل هیدروگراف واحد لحظه ای ژیومورفولوژیکی احتمالاتی PGIUH متشکل از سیستم رده بندی آبراهه ای استراهلر و قوانین هورتن و نیز زمانهای پیمایش جریان آب بر روی سطوح (جریان روزمینی) و آبراهه های رده های مختلف حوضه جهت پیش بینی هیدروگراف خروجی حوضه است. روابط تجربی گوناگونی جهت تخمین زمان پیمایش جریان های روزمینی و آبراهه ای در دنیا ارایه شده است. در این نوشتار پس از استخراج داده های مورد نیاز ، صحت محاسباتی تعدادی از روابط زمان پیمایش از طریق مقایسه آماری هیدروگراف های پیش بینی شده با تعداد 10 واقعه بارش- رواناب در حوضه امامه مورد آزمون قرار گرفته است. نتایج نشان می دهد که زمان پیمایش سطوح تاثیر قابل ملاحظه ای بر تخمین هیدروگراف حوضه نداشته است ولی تاثیر زمان پیمایش آبراهه ها و به خصوص آبراهه اصلی تعیین کننده بوده است. همچنین هیچ یک از روابط زمان پیمایش آبراهه ای قادر نبوده است تمامی وقایع را به خوبی شبیه سازی کند. برخی از روابط وقایع معمول و پرتکرارتر حوضه و تعدادی دیگر از روابط وقایع شدیدتر و با دبی اوج بالاتر را بهتر تخمین زده اند. همچنین نوع پارامترهای بکار رفته در روابط در نتایج به دست آمده تاثیرگذار بوده اند. بکارگیری پارامتر وسعت حوضه آبگیر (A) در یکی از روابط، میانگین نتایج جاصل از شبیه سازی 10 واقعه را بهبود بخشیده است و نیز پارامتر شدت بارش موثر (i_e) در یکی دیگر از روابط باعث شده تا برخلاف سایر روابط، هم برخی از وقایع کم شدت و پرتکرار و هم تعدادی از وقایع پرشدت و دارای دبی اوج بالاتر در بین بهترین نتایج آن قرار گیرد.

    کلید واژگان: مدل PGIUH, زمان پیمایش, جریان روزمینی, جریان آبراهه ای, هیدروگراف سیل
    Mahdi Amini, Muosa Hosseini *, Shirin Mohammadkhan, Ebrahim Moghimi, Mojtaba Yamani

    The hydrograph shape, volume, peak discharg, and time to peak are important factors that should be considered in flood prediction and surface - water management problems. Rainfall and watershed characteristics affect runoff, and thus, hydrograph aspects. Numerous models have been developed to estimate hydrographs based on a variety of parameters. The PGIUH model is a geomorphologically - based model that has a probabilistic structure applying Strahler ̓s stream ordering scheme and Horton's laws and overland/streamflow travel times of different overland/stream orders to predict hydrographs. In the hydrological literature, the watershed response time to the rainfall is commonly characterized by the concepts including " time of concentration", "lag time", and"travel time", and the latter is applied in the PGIUH model to refer to the time it takes water to travel from one location to another; both on overland surfaces(overlandflow travel time) and in streams(streamflow travel time). .Different physically and empirically - based relationships have been developed to estimate travel time. Regarding the invariable probabilistic structure of the model, one can test the computational accuracy of the various travel time relationships based on the results of the model runs in comparison with observatory rainfall-runoff data The aim of this paper is to assess 10 travel-time relationships (5 overlandflow and 5 streamflow relationships) by comparing the estimated hydrographs with 10 observatory hydrographs in the Amameh watershed, located in the Alborz mountains, northern Iran. To reach the goal, some observatory hourly rainfall-runoff data of the watershed were obtained from two companies related to Iran ҆ s Ministry of Energy and 10 appropriate data were separated. For each of the runoff data, the total runoff ordinates were separated from the baseflow to derive the direct runoff hydrograph (DRH). Knowing the runoff depth produced by each event, the hourly effective rainfall amounts of that event were determined using the 𝜙-index, so that the total of all effective rainfall amounts of the whole rainfall duration would be equal to the runoff depth.On the other hand, the geomorphologic, topographic, and hydraulic paramaters needed to be used in the probabilistic structure and travel time relationships were obtained from the 12.5 m digital elevation model (DEM), the Google Earth satellite images and the previous papers regarding the study area. Different combinations of travel time relationships were applied at numerous model runs (One overlandflow plus one streamflow relationships at each run) to derive various IUHs. The hydrograph ordinates were obtained by multiplying the hourly effective rainfalls by the IHUs` ordinates and were compared with observed hydrographs statistically using such criteria as root mean square error (RMS), coefficient of efficiency (CE), error of peak discharge (〖Eq〗_p), and error of time to peak discharge (〖Et〗_p). The results showed that overlandflow travel-times did not contribute significantly in the hydrograph characteristics (in terms of peak flow, time to peak, and runoff volume), however, the effect of streamflow travel times, especially those related to the main stream has been decisive. This could be due to the short water flow paths, and thus, travel times on the overland surfaces, and consequently, least contribution of the overlandflow in the time of concentration at each event as opposed to the streamflow Also, no of the streamflow travel time relationships has simulated all the events accurately. Some of the relationships (the Bransby-Williams and the Gupta et al with gamma of 0.6 to 0.7 relationships) have estimated more frequent normal rainfall-runoff events more precisely wich is represented in better mean statistical results of the 10 simulations and some others (the Kirpich, Johnston-Cross, and the Gupta et al with gamma of 0.2 to 0.4 relationships) have done the same for more intense less repeated events with higher peak discharges.This is because various events result in different streamflow velocities, and thus travel times, and various relationships have estimated streamflow travel times, especially those of the main stream, differently. Also, the the types of parameters used in the relationships have affected the results The watershed area (A) parameter involved in the Bransby-Williams relationship has led to more accurate average results obtained from the simulation of 10 rainfall-runoff events and the effective rainfall intensity (i_e ) parameter used in the Lee et al relationship has, unlike other relationships, led some of both the more frequent low intensity and more intense higher discharge events to be as of its best estimations. It is concluded,thus, that not a single streamflow travel time relationship can best estimate all the rainfall-runoff events in the PGIUH model, however, there may be one relationship that can be best adapted to the mean hydroclimatological conditions in a watershed and lead to best mean statistical results among others. For more rare events, other relationships whose results are far from mean hysroclimatological conditions of the watershed can be applied

    Keywords: PGIUH model, travel-time, overlandflow, streamflow, flood hydrograph
  • فاطمه کیارستمی*، مجتبی یمانی، ابوالقاسم گورابی، سید محمد زمانزاده، محمدرضا قاسمی

    پوسته زمین بر اثر عوامل زمین ساختی و حرکات فشارشی و کششی حاصل از آن به طور مداوم در حال تغییر و تحول است. تغییر در شکل نیمرخ طولی رودخانه ها یکی از پیامدهای تاثیرات زمین ساخت فعال بر شبکه های آبراهه ای است. در این پژوهش هدف اصلی بررسی تاثیر زمین ساخت فعال در قالب حرکات امتدادلغز و ترافشارشی گسل دامغان بر روی ساختار مورفولوژیکی ارتفاعات سیاه کوه در شمال دامغان است. بدین منظور با استفاده از اطلاعات ارتفاعی نقشه رقومی ارتفاع 5/12 متر راداری و با استفاده از الگوریتم D8 به استخراج آبراهه های منطقه پرداختیم و 2 رود اصلی بر سطح ارتفاعات سیاه کوه را مورد بررسی قرار دادیم. در این راستا از رابطه توان رودخانه برگرفته شده از دو متغیر اصلی شیب و مساحت زهکشی رود در قالب یک نمودار لگاریتمی به منظور استخراج پارامترهای تندی و فرورفتگی بهره گرفتیم. افزایش پارامتر تندی بیانگر بالاآمدگی رود در پاسخ به فرایش های فعال می باشد؛ درحالی که افزایش پارامتر فرورفتگی بیانگر عدم عملکرد فرایندهای زمین ساختی به شکل فرایشی و یا مقاومت کم سنگ بستر است. بررسی تاثیر فعالیت گسل دامغان بر روی ارتفاعات سیاه کوه با استفاده از رابطه توان رودخانه نشان داد که حرکات امتدادلغز و ترافشارشی گسل دامغان برجستگی سیاه کوه را در قالب ساختار یک خم گرفتاری با مورفولوژی فوربرگی درآورده است. هرجا رود بر سطح فوبرگ جریان دارد؛ مقادیر بالایی از پارامتر تندی را نشان می دهد و هر جا رود از سطح فوربرگ خارج شده و بر روی رسوبات سست کواترنری مخروط افکنه های اطراف جریان یافته از مقادیر پارامتر تندی کاسته شده و بر مقادیر پارامتر فرورفتگی افزوده شده است.

    کلید واژگان: سیاه کوه, کواترنری, گسل دامغان, مورفوتکتونیک, نیمرخ طولی رودخانه
    Fatemeh Kiaroostami *, Mojtaba Yamani, Abolghasem Gorabi, Seyed Mohammad Zamanzadeh, Mohammadreza Ghassemi
    Introduction

    Identification of active tectonics in an area and its effects on the morphology of landforms is one of the topics that has always been of interest to geomorphologists. Waterways are among the features that flow a wide range of landforms. These features are sensitive to lithological or tectonic changes and react quickly to these changes. The riverbed has been affected by these anomalies and the effects of these anomalies can be studied in the longitudinal profile of the river. In other words, waterways are active tectonic markers that give us information about the characteristics of a landform.

    Materials and methods

    The study area is located in the south of the Eastern Alborz Mountains and is known as the Siah-Kuh Heights. This ridge consists of a set of dolomitic and sandstone rocks of Sibzar and Padha Formation and Damghan fault passes along it. The main purpose of this study is to investigate the morphological and tectonic structure of Siah-Kuh using steepness and concavity parameters based on the anomalies of longitudinal profiles of the rivers based on the uplift and subsidence axes. In order to calculate the rate of steepness and concavity of longitudinal profiles, the stream power low formula is used based on the two main parameters of drainage area and slope of river. This formula is based on a logarithmic plot of the slope and drainage area for which the appropriate regression line is determined. In this regression relation, the slope of the line is the concavity parameter and the intercept is steepness parameters.

    Results and discussion

    The extent of the Siah-Kuh heights among a series of young Quaternary sediments at a distance of 4 km from the main mountain front, the structure of the Siah-Kuh is similar to Foreberg forms. Damghan fault in this area has led to the intersection of Quaternary sedimentary strata related to the surrounding alluvial fans and by creating a transtensional position in the form of a set of trapped traps, the Siah-Kuh Foreberg has appeared as a restraining bend on the surface Which has led to the elevation of the central part and the relative subsidence of both sides of this structure. The eastern part of the Siah-Kuh Foreberg appears to have been covered by Neogene and Quaternary sediments. Its remnants have appeared in the form of deep gorges on the surface. One of the rivers flows on the main surface of Foreberg and the other flows in the drained or buried part of Foreberg. Both rivers have several knick points in their flow path, which are taken from the location of faults and lithological differences of the riverbed. The values of the steepness parameter for the main river and the gully show high values so that the value of this parameter is 121.4 for the main river and 119.96 for the gorges. In contrast, the depression parameter rate in both rivers shows very low and even negative values. (Main river: -0.18 and gorges river: -0.92). Since the sharpness parameter is directly related to the tectonic processes; It can be said that the values of this parameter in both rivers indicate the effect of active tectonics at the level of Foreberg.

    Conclusion

    The studies performed on the study area show that the two factors of active tectonics and lithology have a great impact on the morphological structure of Siah-Kuh Foreberg. Also, factors related to sedimentary flows originating from the uplands of the area have been effective in changing these landforms in the form of burial. Also, the results showed that the use of the method based on longitudinal profile anomalies of the river in the form of steepness and concavity parameters has an effective role in identifying erosion and subsidence axes related to tectonic situation of features in relation to their topographic changes. Slight difference in the amount of steepness parameter in gorges compared to the river on the main surface of Foreberg, especially in the first trends of both rivers, which show high values of steepness parameter with a small difference (1.44), Indicates the existence of an uplift axis in this area, which somewhat confirms the burial of a structure similar to the Siah-Kuh Foreberg under sediments.

    Keywords: Siah-Kuh, Quaternary, Damghan Fault, morphotectonic, Longitudinal profile of river
  • عارفه شعبانی عراقی*، مجتبی یمانی
    بازسازی شرایط آب وهوایی، تغییرات اقلیمی هولوسن و مکانیسم ردیابی آن در شواهد رسوب شناسی و ژیومورفولوژیکی دریاچه های عرض های جغرافیایی مختلف از جمله موضوعات موردتوجه پژوهشگران است. شواهد اقلیمی به جای مانده از این دوره ها کلیدی برای حل ابهامات تحولات آب وهوایی، فرم ها و فرآیندهای ژیومرفیک مناطق مختلف است. این پژوهش بر اساس اهداف آن به بررسی شرایط اقلیمی و تاثیرگذاری آن بر گستره دریاچه ها بر اساس شواهد مرفولوژیکی (پادگانه ها) پرداخته است. این پژوهش در پلایای دامغان واقع در استان سمنان در جنوب شرقی شهر دامغان واقع در نیمه شمالی کشور انجام شده است. در این راستا از داده ها و منابع نوشتاری، آماری، سنجش ازدور، رسوبی و شواهد مرفولوژیکی با استفاده از ابزارها و روش های گوناگون علمی و تخصصی استفاده شده است و در نهایت با جامع نگری موضوع را تحلیل شده است. پس از بررسی منطقه برای اولین بار پادگانه های دریاچه ای در منطقه شناسایی گردید، در مرحله بعد نمونه های برداشت شده از این سطوح مورد آنالیز آزمایشگاهی قرار گرفت و دریاچه ای بودن آن ها تایید شد سپس با استفاده از تکنیک های سنجش ازدور و نقشه کشی بر اساس ارتفاع پادگانه های دریاچه ای ثبت شده سطوح گستره دریاچه تعیین و نهایتا حدود این سطوح با توجه به سایر عوامل طبیعی مانند شیب، جهت شیب، شبکه زهکشی و بررسی های زمین شناسی تصحیح گردید. نتایج حاکی از آن است در پلایای دامغان 2 سطح پادگانه ای وجود دارد که در محدوده جنوب شرقی چاله، تراس دریاچه ای ازنظر ارتفاعی با تراس هایی در دامنه جنوب پلایا همخوانی دارند و بازسازی حد آن ها حد دریاچه یکسانی را مشخص می کند که نشان دهنده اولین سطح دریاچه با عمق حدود 22-24 متر است. همچنین تراس های دریاچه ای در دامنه جنوب غربی پلایا نیز دریاچه ای با عمق حدود 14-15 متر را در کواترنری نشان می دهند.
    کلید واژگان: پلایا, پادگانه دریاچه ای, دریاچه دیرینه, کواترنری, چاله دامغان
    Arefe Shabani Eraghi *, Mojtaba Yamani
    Reconstruction of climatic conditions, Holocene climate change, and its tracking mechanism in sedimentological and geomorphological evidence of lakes of different latitudes are among the topics of interest to researchers. This study aimed to investigate the climatic conditions and their impact on the lake area based on morphological evidence (terraces). This research has been done in Damghan Playa, located in Semnan province in the southeast of Damghan city, located in the northern half of the country. In this research, written and statistical data and sources have been used, sedimentation and morphological evidence using various scientific tools and methods, and finally have analyzed the issue comprehensively. After visiting the area for the first time, lake terraces were identified in the area. In the next step, the collected samples were subjected to laboratory analysis, and the lake environment was confirmed. Then, using remote sensing and mapping techniques based on the height of the recorded lake terraces, the lake area levels were determined, and finally, their boundaries were corrected according to other natural factors such as slope, Aspect, drainage pattern, and geological studies. The results show that there are two terrace levels in Damghan Playa, which in the southeastern part of the lake terrace hole are in height with the terraces on the southern slope of the Playa, and the reconstruction of their boundary shows the same garrison. Eventually, findings show that the first level of the lake with a depth of about 22-24 meters. Also, the lake terraces on the southwestern slope of Playa show a lake with a depth of about 14-15 meters in the Quaternary.
    Keywords: playa, Lake Terrace, Ancient Lake, Quaternary, Damghan Hole
  • ابوالقاسم گورابی*، مجتبی یمانی، شیرین محمدخان، سید جواد حسینی

    ژیومورفولوژی حوضه زنجان رود متاثر از زون های تکتونیکی فعال حاصل از عملکرد تعاملی گسل های سلطانیه، زنجان، طارم، منجیل و گسل هایی است که در این پژوهش مورد بررسی دقیق تر قرار گرفته اند. تعامل این گسل ها این حوضه را به شکل یک فلات کوچک مرتفع ناهمگون نسبت به مناطق پیرامونی و محل مناسبی برای استقرار سکونتگاه های انسانی ساخته است. در این پژوهش برای کشف تاثیر تکتونیک بر ژیومورفولوژی حوضه از تکنیک های دورسنجی و ژیومورفومتری جهت شناسایی خط واره ها و شواهد زمین ساختی استفاده شده است. خط واره ها پس از بررسی به کمک تکنیک های دورسنجی، ژیومورفومتری و میدانی تبدیل به نقشه شده اند. سپس با تحلیل و تفسیر شواهد، ارتباط الگوی دینامیک گسل ها کشف و اثرات آن بر مورفولوژی لندفرم های مختلف با تاکید بر نو زمین ساخت تعاملی شبکه های زهکشی - گسل ها ارایه شده اند. نتایج نشان می دهد که تکتونیک فعال گسل ها به سمت مرکز حوضه و محل زنجان رود متمرکز است. از طرفی تبعیت مورفولوژی و روندهای توپوگرافیک مختلف حوضه و همچنین کانال زنجان رود و بسیاری از زهکش ها با خط واره های استخراجی به کمک تکنیک های ژیوومورفومتری، به وضوح کارایی ژیومورفومتری جهت ارزیابی و اثبات تاثیر زمین ساخت بر ژیومورفولوژی حوضه ها را نمایان می سازد. اگر چه زلزله مخربی در منطقه گزارش نشده؛ ولی وجود شواهد مورفولوژیک و قطع نهشته های کواترنر تا هولوسن بیانگر تغییر شکل فعال منطقه هستند. براین اساس به نظر می رسد سیستم های گسلی حوضه پتانسیل ایجاد زمین لرزه های با بزرگایی بسیار بالاتر از آنچه تاکنون رخ داده اند را دارند که این حاکی از ضرورت برنامه ریزی بر مبنای مطالعه دقیق گسل های منطقه است.

    کلید واژگان: تکتونیک فعال, زنجان رود, ژئومورفومتری, ناهنجاری, هیدرو ژئومورفولوژی
    Abolghasem Goorabi *, Mojtaba Yamani, Shirin Mohammadkhan, Said Javad Hoseini

    The geomorphology of the Zanjanroud basin is affected by the active tectonic zones resulting from the interaction of the Soltanieh, Zanjan, Tarem, and Manjil faults and the faults that have been investigated more closely in this research. The interaction of these faults has made this basin in the form of a small high plateau, heterogeneous compared to the surrounding areas and a suitable place for the establishment of human settlements. In this research, remote sensing and geomorphometric techniques have been used to identify the lineaments and tectonic evidence in order to discover the tectonic effect on the geomorphology of the basin. The contour lines have been converted into a map after checking with the help of telemetry, geomorphometry and field techniques. Then, by analyzing and interpreting the evidence, the relationship between the dynamic pattern of the faults and its effects on the morphology of different landforms is presented with an emphasis on the interactive reconstruction of drainage networks and faults. The results show that the active tectonics of the faults are concentrated towards the centre of the basin and Zanjanroud area. On the other hand, the compliance of the morphology and topographical trends of the basin, as well as the Zanjan River canal and many drainages with the extraction lines with the help of geomorphometric techniques, clearly shows the effectiveness of geomorphometry to evaluate and prove the impact of terraforming on the geomorphology of the basins. Although no destructive earthquake has been reported in the region, But the presence of morphological evidence and the interruption of Quaternary to Holocene deposits indicate the active deformation of the region. Therefore, it seems that the fault systems of the basin have the potential to create earthquakes with a much higher magnitude than what has happened so far, which indicates the necessity of planning based on a detailed study of the faults in the region.

    Keywords: active tectonics, anomaly, geomorphometry, Hydrogeomorphology, Zanjanrud
  • Khadijeh Mohammadi *, Ebrahim Moghimi, Mehdi Zare, Mojtaba Yamani, Masoud Mojarab

    The plate tectonics of Northeast Afghanistan are complex with diffuse and sparse seismicity in the broad plate deformation zones embedded by a number of micro-plates in the Badakhshan. Geothermal techniques in this area provide an important tool for investigating plate tectonic kinematics and identifying the approximate plate tectonic geometries. In this paper, we have processed Seismic centers data (1909–2022) collected by EMME and USGS catalogs and Geothermal data by Landsat 8 satellite images. Modeling of tectonic lines by geothermal energy and seismicity trends are studied. We find that the deformation in Northeast Asia can be well described by several blocks, independent of the Eurasian plate motion. Landsat images showed the important geothermal lines with medium and low importance. Tectonic micro-zones were defined by placing lines of high importance and medium importance together. According to the trend of seismicity centers concentrated from east to west of the Badakhshan region, the e result shows the continuation of east-west fractures. This east-west trend in the center of Badakhshan is located exactly in the fracture and the edge of the micro-zone plate with medium importance. The transformation of medium-importance fractures into high-importance fractures in the geographical center of Badakhshan can cause more important earthquakes in the region.

    Keywords: Slip tendency, Enhanced geothermal systems, Seismicity, Badakhshan
  • فاطمه کیارستمی*، مجتبی یمانی، ابوالقاسم گورابی، سید محمد زمان زاده، محمدرضا قاسمی

    ارتفاعات البرز شرقی واقع در شمال پلایای دامغان، به سبب وجود گسل های متعدد همچون گسل آستانه، دامغان، تزره و عطاری جزء نواحی فعال زمین ساختی ایران به شمار می رود. هدف اصلی در این پژوهش شناسایی تغییرات زمین ساختی و فرسایشی این بخش از ارتفاعات البرز و نواحی اطراف آن شامل پلایای دامغان در قالب پیدایش محورهای فرایش و فرورفتگی در طی کواترنری می باشد که منجر به شکل گیری لندفرم های متعددی شده است. در این راستا، از روش تحلیل و بررسی نقشه های همپایه و تفریقی برمبنای ناهنجاری های ایجاد شده در رده های آبراهه ای متاثر از فرایندهای فرایشی و فرسایشی فعال در کواترنری استفاده به عمل آمد. بررسی های انجام شده بر روی منطقه مورد مطالعه نشان می دهد که دو عامل زمین ساخت فعال و سنگ شناسی بر روی ساختارهای مورفولوژیک و لندفرم های منطقه تاثیر بسیار زیادی دارند. نتایج نشان می دهد که گسل های منطقه در طی کواترنری فعال بوده و با سازوکارهای متفاوت رانده و امتدادلغز که در برخی نواحی دارای جایگاه های تراکششی و ترافشارشی نیز بوده اند، مجموعه ای از لندفرم های فرایش یافته یا فروافتاده را در ناحیه دامغان به وجود آورده اند. برخی از این لندفرم ها نشانگر عدم تطابق ساختاری البرز متاثر از فعالیت گسل های ناحیه در ارتباط با عامل مهم سنگ شناسی می باشند.

    کلید واژگان: لندفرم, گسل, نقشه همپایه, نقشه تفریقی, دامغان
    Fatemeh Kiaroostami *, Mojtaba Yamani, Abolghasem Goorabi, Seyed Mohammad Zamanzadeh, MohammadReza Ghassemi
    Introduction

    Damghan area has been considered by earth scientists due to the existence of numerous active faults. These faults with slow and progressive movements have led to changes in the shape of landforms in the area. Even during the history, the activity of these faults led to major earthquakes such as Qumis earthquake in 856 A.D. This earthquake led to the complete destruction of Qumis province in present-day Damghan. Researchers in the area, including Hollingsworth et al 2010., have concluded that major faults in the area, such as the Astaneh and North Damghan faults, have ruptured during the Qumis earthquake. The changes in landforms and high potential of faults in creating seismic events indicate their continuous activity during Quaternary up to now. To study these changes, we need those features that are sensitive to tectonic and erosive events. Rivers are one of these features that react quickly to active tectonic and erosion changes. The main purpose of this study is investigation of the changes in landforms using anomalies in stream orders. Because there is a hypothesis that claims tectonic and erosive changes lead to irregularity in Strahler orders of streams. In this study we use isobase and differential map method to investigate this hypothesis.

    Materials and Methods

    Sensitivity of drainage network to tectonic processes and geological contradictions leads to changes and irregularities in river orders. Isobase maps are extracted from information about the spatial classification of rivers and their elevation information in the environment. In fact, these maps show the relationship between the pattern of waterways and the topography of landscapes. Streams with the same Strahler order are formed by the same geological events, and most likely the same order is the same age. We can draw iso base maps for different stream orders. Early orders (1-3) are mostly more sensitive to tectonic events. These early orders due to flow along seams and fault gaps are representative of neotectonic. Rugged structures in the lithology of the region can limit the evolution and development of the early orders, and therefore in these areas the values of the isobase map increase. But isobase map of evolved orders can represent longer periods, such as the Quaternary or Pleistocene. Because evolved orders are formed over longer periods and are able to show older tectonic and erosive events. Differential maps are obtained from the difference in height between the maps of the evolved orders and the present day topography map.

    Results and Discussion

    Examination of the isobase map of the primary orders show that most of the values related to the map can be seen in the west and north of the region. These areas are based on mountainous structures. The high values of the isobase map in these areas indicate that the northern and western parts, affected by neotectonic activities and the development of fault gap and seams, have more primary orders of rivers. Because most of these primary orders are formed and developed along these levels of weakness. Resistant lithology of the area has also prevented the development of these orders. The highest value of them is 3830-2312 meters. The differential map prepared from the study area shows a wide range of positive values indicating uplift and negative values indicating subsidence. By examining these values, we can understand the features related to tectonics and geomorphology of various landforms in the region. The highest values of 1191 to 800 meters are related to the high mountain structures of Eastern Alborz in the north and west of the region. The decrease in the value of the differential map indicates the effect of tectonic subsidence on the morphological landforms of the region. The Astaneh pull apart basin in the western part of the region shows the amount of subsidence between -4 to -1 meters. Also, the southern playa of Damghan in the form of a concave foreland basin affected by active faults in the region shows negative values, which indicates the existence of a submerged basin with high sedimentation potential.

    Conclusion

    Studies conducted on the area show that the two factors including active tectonic and lithology have a great impact on the morphological structures and landforms of the area. The results of isobase map and the differential map show and confirm this issue. The methods used in this study to investigate the tectonic activity of the faults in the area indicate their activity during the Quaternary. These faults have different mechanisms of thrust and streak slip which in some areas also have transtensional and transpressional position; they have created a collection of uplifted or concave landforms in Damghan area. The spatial relationship between different values from north to south in the prepared maps indicates the creation of an equivalent states between topographic growth and its destruction in lower altitudes. Based on the studies, we confirm that the preparation of isobase and differential maps can be a suitable method for studying and examining morphological structures. Also studies related to differential map show anomalies in drainage networks and uplift processes associated with active Quaternary landforms can be quantified by these maps. Using baseline and differential maps is one of the appropriate methods to study the Plio-Quaternary tectonics in an area. This study confirms the work of previous researchers based on the available information and documents related to the study area.

    Keywords: Landform, Fault, Isobase map, Differential map, Damghan
  • Khadijeh Mohammadi *, Ebrahim Moghimi, Mehdi Zare, Mojtaba Yamani, Masoud Mojarab
    The Badakhshan region in the northeast of Afghanistan has a complex geology that was created as a result of the collision of the Indian and Eurasian blocks. Using EMME seismographic catalogue data, with updates (years 2011-2021), from the website of Harvard University, International Seismic Research Centre (ISC) and USGS, a catalogue of earthquake epicentres. A device has been prepared. Then, according to the last earthquake of magnitude 7.2 in 2015, coefficients a and b have been calculated at the surface and depth. This value for b value is 1.0 in the northern half and a value is 7.9 in the southern half. The numerical increase of a and b in the central and southern half after the 2015 event has been quite evident. Earthquake prediction in the southern half of Badakhshan will increase in the future. According to the trend of earthquakes, the results indicate that contrary to the direction of the main fault in North Badakhshan (North-South), the highest frequency of earthquakes is 4≤ at a depth of 70-150 km, earthquakes are 5≤, and the depth of 150-300km from the earth and finally 6≤ at the depth of 300-700km in the east-west direction. This area is exactly where the Pamir Corridor plate subducts due to the pressure of the Indian plate in the west and southwest of Badakhshan. The tectonic situation of the region subducts to the south and southwest and causes compression and bending in the south of Badakhshan.
    Keywords: Himalayan Alpine belt, Pamir, the Hindu Kush, seismicity, Badakhshan, Afghanistan
  • شهناز علیزاده، مجتبی یمانی*، محمدرضا ثروتی، منیژه قهرودی

    پژوهش های دیرینه شناسی موید افت وخیز تراز آبی دریای خزر در قالب ارقام متفاوت تا چندده متر است. سواحل دریای خزر دارای توپوگرافی و کاربری اراضی متفاوت از جمله اراضی پست مرتبط با مصب رودخانه ها، خورها، یا پیشرفتگی های آب دریا در خشکی و سواحل نسبتا بلندتر ماسه ای و شنی است. عموما شیب پس کرانه بسیار اندک است. این عوامل شرایط مساعدی را برای غرقاب شدن زمین ها در زمان افزایش سطح تراز آب دریا یا بالا آمدن سطح پیزومتری آبخوان های ساحلی فراهم می کند. در این پژوهش با استفاده از تحلیل زمانی مکانی به بررسی تغییرات خطوط ساحلی تالش تا انزلی در طول 45 سال در قالب سلول‏های ساحلی پرداخته شده است. برای این منظور با استفاده از نرم افزارهای Arc GIS خطوط ساحلی سال‏های 1975 و 1997 و 2020 و سپس با استفاده از نرم افزار DSAS میزان تغییرات خط ساحلی استخراج شدند. نتیجه پژوهش حاکی از آن است که تغییرات خط ساحلی در محدوده تحت بررسی کاملا تحت تاثیر تغییرات سطح آب دریای خزر قرار داشته است؛ طوری که 77 درصد از خط ساحلی دچار پس روی بیش از 30 متر شده است. در این میان فعالیت های انسانی نیز تا حدودی مانع ناپایداری خط ساحلی در اثر تغییرات سطح آب دریای خزر شده است.

    کلید واژگان: پایداری ساحلی, سلول ساحلی, کرانه غربی خزر, DSAS
    Shahnaz Alizadeh, Mojtaba Yamani *, Mohammadreza Sarvati, Manijeh Ghahroudi Tali

    Neglecting coastal erosion and its changes can lead to environmental hazards, which are among the main factors affecting human communities and facilities. Paleontological research demonstrates tens of meters of fluctuation in the water level of the Caspian Sea. The shores of the Caspian Sea have variable topography and land use, including lowlands (estuaries of rivers, gulfs, and progradation) and sandy uplands. In lowlands, there is a slight slope that causes flooding of lands when the sea level rises, as well as an increased piezometric level of coastal aquifers. This study investigates changes in the coastal line from Talesh to Anzali over a period of 45 years using spatiotemporal analysis in the form of coastal cells. For this purpose, ArcGIS software was used to extract the coastal lines of 1975, 1997, and 2020. Then, using DSAS software, the amount of changes in the coastline was determined. The research results showed that changes in the coastal line in the study area were entirely influenced by the fluctuations of the Caspian Sea level, with 77% of the coastal line experiencing more than 30 meters of retreat. Human activities have somewhat prevented the instability of the coastline due to changes in the water level of the Caspian Sea.

    Keywords: Coastal Sustainability, Coastal Cell, the west bank of the Caspian Sea. DSAS
  • فاطمه مرادی پور*، مجتبی یمانی، انور مرادی

    فرایندهای مختلف زیستی و زمین شناختی به ویژه فرسایش منجر به تنوع ویژگی های محیطی می گردد که تحت مفاهیمی همچون ژیودایورسیتی و بیودایورسیتی مورد بررسی قرار می گیرند. در سال های اخیر، مفهوم جدیدی تحت عنوان ژیوبیودایورسیتی معرفی شده که بر مکان های با اهمیت بالای ژیودایورسیتی و بیودایورسیتی تمرکز دارد. باتوجه به اهمیت شناسایی این مناطق برای اهداف حفاظتی و بهره برداری پایدار، در این تحقیق به بررسی ژیوبیودایورسیتی منطقه اشترانکوه واقع در استان لرستان پرداخته شده است. داده های تحقیق شامل عناصر مختلف زمین شناسی، ژیومورفولوژی، آب، خاک، پوشش گیاهی و حفاظت است که از طریق مطالعات کتابخانه ای -اسنادی و میدانی جمع آوری شده اند. در ادامه، برای دستیابی به اهداف تحقیق و تجزیه وتحلیل داده ها از شاخص GBI بهره گرفته شده است. این شاخص از طریق ایجاد سلول های شش ضلعی و یک ماتریس تحلیلی، چهار زیرشاخص ژیودایورسیتی، ژیومورفولوژی، پوشش گیاهی و سطوح حفاظتی را ارزیابی و تلفیق نموده و مناطق با اهمیت بالای ژیوبیودایورسیتی را مشخص می کند. نتایج به دست آمده نشان داد که از نظر شاخص ژیودایورسیتی بیش از 62 درصد، از نظر شاخص ژیومورفولوژی حدود 35/59 درصد، از نظر شاخص پوشش گیاهی حدود 20/59 درصد از منطقه موردمطالعه دارای ارزش زیاد و خیلی زیاد هستند. درحالی که از نظر شاخص حفاظت بیش از 70 درصد منطقه موردمطالعه در سطح حفاظتی کم و خیلی کم توزیع یافته اند. در نهایت، از نظر ژیوبیودایورسیتی تعداد 2587 سلول شش ضلعی (35/44 درصد منطقه) دارای ارزش زیاد و خیلی زیاد هستند که عمدتا در داخل منطقه حفاظت شده اشترانکوه به ویژه در شرق و جنوب دریاچه گهر، امتداد دره نی گاه و منطقه وزمدر توزیع یافته اند؛ بنابراین، ضروری است ضمن توجه به نتایج مطالعه حاضر، یک رویکرد مدیریت یکپارچه در منطقه اشترانکوه به ویژه در بخش های حفاظت شده توسط دستگاه های ذی ربط پیاده سازی شود که ارزش های ژیوبیودایورسیتی منطقه برای نسل های مختلف حفظ گردد.

    کلید واژگان: ژئودایورسیتی, بیودایورسیتی, ژئوبیودایورسیتی, شاخص GBI, اشترانکوه
    Fatemeh Moradipour *, Mojtaba Yamani, Anvar Moradi

    Various biological and geological processes, especially erosion, lead to the diversity of environmental features, which are studied under concepts such as geodiversity and biodiversity. In recent years, a new concept called geobiodiversity has been introduced, which focuses on places with high geodiversity and biodiversity importance. Considering the importance of identifying these areas for conservation purposes and sustainable uses, in this research, the geobiodiversity of the Oshtorankuh area located in Lorestan province has been investigated. The research data includes various elements of geology, geomorphology, water, soil, vegetation and environmental protection level, which have been collected through library-documentary and fieldworks. In the next step, the GBI index has been used to achieve research goals and data analysis. This index evaluates and integrates four sub-indexes of geodiversity, geomorphology, vegetation and protection levels through the creation of hexagonal cells and an analytical matrix, and finally identified the areas with high geobiodiversity value. The obtained results showed that in terms of geodiversity index, more than 62 percent; in terms of geomorphology index, about 59.35 percent; in terms of vegetation index, about 59.20 percent of the studied area have high and very high values. While in terms of protection index, more than 70 percent of the studied area is distributed in low and very low protection levels. Finally, in terms of geobiodiversity, the number of 2587 hexagonal cells (44.35 percent of the area) have a high and very high value, which are mainly inside the Oshtorankuh protected area, especially in the east and south of Gahar Lake, along the Neygah Valley and in the Vazmdar area have been distributed. Therefore, it is necessary to implement an integrated management approach to preserve the geobiodiversity values in the Oshtorankuh region by the relevant organizations and with the participation of local communities.

    Keywords: Geodiversity, Biodiversity, Geobiodiversity, GBI Index, Oshtorankuh
  • شهناز علیزاده، مجتبی یمانی*، محمدرضا ثروتی، منیژه قهرودی تالی

    مناطق ساحلی از طرفی تحت تاثیر فرایندهای هیدرودینامیک دریا و خشکی و از طرف دیگر تحت تاثیر فعالیت های انسانی اطراف خط ساحلی می باشند که اغلب پتانسیل بالایی در آسیب پذیری دارند که باید موردتوجه قرار گیرند. پژوهش های دیرینه شناسی موید افت وخیز تراز آبی دریای خزر در قالب ارقام چند ده متری است.  سواحل دریای خزر دارای توپوگرافی و کاربری اراضی متفاوتی ازجمله اراضی پست مرتبط با مصب رودخانه ها، خورها و یا پیشرفتگی های آب دریا در خشکی و سواحل نسبتا بلندتر ماسه ای و شنی است. عموما شیب پس کرانه بسیار اندک است. این عوامل، شرایط مساعدی را برای غرقاب شدن زمین ها در مواقع افزایش سطح تراز آب دریا و یا بالا آمدن سطح پیزومتری آبخوان های ساحلی فراهم می کند. هدف این تحقیق تعیین آسیب پذیری خط ساحلی غرب دریای خزر (تالش تا انزلی) با استفاده از روش تحلیل سلسله مراتبی و تکنیک مقایسه زمانی-مکانی تغییرات است. متغیرهای موردبررسی در این پژوهش، شامل تغییرات ایوستاتیک تراز دریا، ژیومورفولوژی، توپولوژی و کاربری اراضی می باشد. نتیجه پژوهش حاکی از آن است که سواحل با آسیب پذیری کم متعلق به نواحی اطراف موج شکن پره سر و مناطقی است که توسط جریان های خشکی تقویت می شوند و 2/56 کیلومتر از 4/93 کیلومتر (60 درصد) ساحل موردمطالعه، نیازمند توجه ویژه در جهت تعیین رویکردهای مدیریتی برای حفاظت از ساحل، جلوگیری از فرسایش ساحلی و تقویت و تغذیه ساحل می باشد.

    کلید واژگان: آسیب پذیری, تالش- انزلی, خط ساحلی, کرانه غربی خزر, DSAS
    Shahnaz Alizadeh, Mojtaba Yamani*, Mohammadreza Sarvati, Manijeh Ghahroudi Tali

    The shores of the Caspian Sea have different topography and land use, including lowlands associated with the mouths of rivers, bays, or seawater advances on land and relatively higher sandy and sandy beaches. There is a very low slope in the lands behind the beach. Paleontological research shows the rise and fall of the water level of the Caspian Sea in the form of figures of several tens of meters. the purpose of this research is to analyze the degree of vulnerability of 93.4 km of coastlines in three cities of Talesh, Rezvanshahr and Anzali in Gilan province. In this research, four variables were used in the form of 12 subcategories, using the hierarchical analysis method, to achieve the vulnerability index of the coastal area of ​​Talesh to Anzali cities. According to the mentioned references and the purpose of the study, the desired variables include sea level changes, land topography, geomorphology and land use. Landsat satellite images, topographic maps 1:25000 and digital model of 12.5 meters height of the research area as well as SAGA, IDRISI, ENVI, DSAS and Arc GIS software were used for analysis. The results showed that the beaches with low vulnerability belong to the areas around PareSar breakwater, as well as areas strengthened by onshore currents. Therefore, 56.2 km (60%) of the studied coast needs special attention in order to determine management approaches to protect the coast, prevent coastal erosion and strengthen and nourish the beach.

    Keywords: Vulnerability, Talesh-Anzali, Coastline, Western shores of the Caspian, DSAS
  • امیر صفاری، مجتبی یمانی*، شیرین محمدخان، نادر پروین، موسی عباسی

    این مدل رودخانه های آنابرنچ را بر اساس پارامترهای توان جریان، میزان و اندازه بار بستر، اندازه ذرات کرانه ها، میزان جا به جایی جانبی، نسبت طول جزایر به پهنای مجرا در شش طبقه تقسیم بندی می کند که نتایج نشان داد رودخانه گادر در محدوده نوع شماره پنج و شاخص میزان به هم پیوستگی و افزایش عمودی جزایر و سینوسیتی مجرا در محدوده نوع یک قرار دارد. جزایر در بازه های شریانی و مستقیم به دلیل پهنای بیش تر از بازه های دیگر رشد بیش تری داشته اند و در بازه میاندری واقع در بین ارتفاعات کیله شین تا روستای بیمضرته رشد کمتری است. در بازه سوم که جنس رسوبات بستر و کناره رودخانه و دره ای که رودخانه در آن جریان دارد از نوع فرسایش پذیری است و عرض بستر رودخانه زیاد بوده ولی در بازه اول که جنس رسوبات بستر و کناره رودخانه از نوع سازندهای مقاوم به فرسایش می-باشد تغییرات رودخانه ای کم تر یا تغییرات بسیار کم بوده است. رودخانه گادر با هر شش نوع رودخانه شاخه شاخه از منظرهایی دارای شباهت است و در حالت کلی این مجرا با طرح نانسون و نایتون انسجام و مطابقت کامل را ندارند.

    کلید واژگان: رودخانه گادر, پایداری آبراهه, مدل نانسون و نایتون, تغییرات بستر
    Amir Saffaari, Mojtaba Yamani *, Shirin Mohammadkhan, Nader Parvin, Mousa Abbasi

    Understanding the Attributes and Interactions of Forms and Processes Governing River Systems that Understand the Behavior of Rivers in Temporal and Spatial Bounds The importance of developing conceptual models for the environment is of particular importance. There are rivers. In this study, the stability of the Gadar River waterway based on the Nanson and Knight models is evaluated to evaluate the dynamic behavior of the Gadar river and its effect on the river bed changes based on the Nanson and Knighton designs. The aim of this study. The research method is a descriptive-analytical one. Required parameters were extracted from hydrometer station statistics, fieldwork, topographic maps, land use maps, Google Earth application and Auto Cad, WMS9.1, Smada and ARC GIS software. This model divides the Anabench rivers into six classes based on flow power parameters, bed load size, particle size, lateral displacement, islet length to channel ratio. In the range of type five and index of the degree of coherence and vertical increase of islands and sinusoidal ducts are in the range of type one. The islands have grown more rapidly in the arterial and direct intervals because of the greater widths than in the other, and in the Meander interval between the Kiel-Sheen heights to the low-lying village. In the third period, the sediment type of the riverbed and the valley where the river flows is erodible and the width of the riverbed is high, but in the first period, the sediment and bedrock are of the erosion resistant formations. Either there were fewer river changes or very little change. The Gadar River is similar to any of the six tributary tributary rivers and, in general, this channel is not fully coherent with the Nanson and Neyton designs.

    Introduction

    Rivers are one of the best geomorphic landscapes of the earth, where the link between the system of forces and the forms of roughness can be clearly understood. Studying the morphological pattern of rivers is essential for understanding current conditions and their potential for future changes, and only then can their natural responses to natural changes or actions resulting from the implementation of remediation schemes be possible. It predicted the direction and fixation of the edges and recognized the extent of their displacement and variations in their dimensions and patterns. In the northwestern part of the country, developed river systems play an essential role in the geomorphological developments of the region. The study area is located in the city of Ashnoye in northwest of the country. The purpose of this study was to investigate and evaluate the dynamic behavior of the Gadder River and its effect on river bed changes based on Nanson and Newton designs.

    Data and Methods:

    The research process involved collecting data, field studies, generating information layers and adapting them to the status quo, analyzing each layer to investigate the role of the Gadder River morphodynamics in canal stability and evaluation based on the model. Nanson and Nathan. To evaluate the Gadder River based on this model parameters such as flow power, bed load size and size, particle size of the boundaries, lateral displacement ratio, islet length to channel width, coherence rate and vertical islet and channel sinusitis Used. Finally, the role of each of the variables was identified as influencing factors in the stability of the Gadder River.

    Results and discussion

    In areas where the conduit turns into an anchor, the slope of the upstream stream is minimized and changes noticeably. At the end, when the slope decreases sharply, the river changes into an arterial one. More than 95 percent of the coarse-grained sediments are due to the high river discharge to carry the coarse-grained sediments and to the greater adhesion of the riverbanks that are prone to coarse-grained sediments.
    The erosion of the river bed (Push Abad village to Darband village) was also observed in the sections where the sediment type was erodible (third interval). In areas where the sediment type is bedrock-resistant, there have been fewer or very minor river changes, such as the first section. The arterial and direct intervals have increased more than other intervals due to the greater width and in the meandering interval between the Kilehin heights to the village of Hazrat Zaza. The fluctuations and changes in the sinocyte coefficient of the river Gadar were lower in the first interval due to the first mountainous interval due to the river route. In the second and third intervals, the rate of sinocytic coefficient increased in the year 1396 compared to the year 1395, indicating a complex increase in the rivers in these two intervals, resulting in a change in river morphology in these intervals. The comparative results based on the evaluation and the parameters of the Gadder River in different types of design indicate that the Gadder River has similarities with each of the six types of Anabench rivers and, in general, this channel coincides with the Nanson and Knighton designs. Do not match perfectly.

    Conclusion

    The Gadar River islands have grown more in arterial and direct intervals due to their greater width than in other meandering intervals, between the Kileen Heights to the lowland village. In the third period, the sediments of the riverbed and the valley where the river flows are erodible and the width of the riverbed has been displaced for most of the length of this section about 10 to 15 meters. However, during the first period, the sediment type of the riverbed is a type of erosion resistant formations. In the specific and local formation of this anterarchic arterial pattern, neotectonics played the most important role as a locus-setting regulator. The locally developed set of these factors has been a factor in the complete non-conformity of the Gadder River with the Nanson and Newton designs.

    Keywords: Gadder River, Channel stability, Nanson, Neyton Model, bed Changes
  • عبدالکریم ویسی*، ابراهیم مقیمی، مهران مقصودی، مجتبی یمانی، موسی حسینی

    توده کارستی شاهو در شمال غرب استان کرمانشاه به واسطه گستردگی سازندهای آهکی و وجود گسل ها و درزه های زمین شناختی از پتانسیل زیادی برای کارست زایی برخوردار است. هدف از این پژوهش مدل سازی مکانی تحول کارست در این منطقه است. در این پژوهش 10 عامل محیطی تاثیرگذار در تحول کارست استفاده گردیده است. دولین های کارستی منطقه با استفاده از روش CLC استخراج گردید. برای بررسی ارتباط میان دولین ها و عوامل موثر بر تحول کارست از نظریه تابع اطمینان شهودی استفاده شد و وزن طبقه های هر عامل مشخص شد. نتایج نشان داد که بیشترین میزان تحول کارست در شیب های 5-0 درصد، جهت شیب های شمالی و هموار، ارتفاع بالاتر از 2500 متر، فاصله نسبتا کم از آبراهه ها (200-100 متر)، فاصله کم از گسل (کمتر از 1000متر)، سازند توده-ای بیستون، زمین های مرتعی و جنگل های نیمه انبوه، دامنه های مقعر و مناطق پربارش قرار دارد. نقشه پهنه بندی تحول کارست با استفاده از مدل جمعی تعمیم یافته در نرم افزار آماری R برای منطقه تهیه شد. نتایج قابلیت بالای تحول کارست این منطقه را نشان می دهد به طوری که 27درصد منطقه در طبقه با تحول زیاد و 37 درصد آن در منطقه با تحول متوسط واقع شده است درحالی که تنها 17 درصد از کل منطقه در پهنه با تحول کارست خیلی کم واقع شده است. مطابقت بالای نتایج به دست آمده با واقعیت منطقه موردمطالعه، بیانگر کارایی بالای مدل است.

    کلید واژگان: تحول کارست, دولین, داده کاوی, شاهو
    Abdolkarim Veysi *, Ebrahim Moghimi, Mehran Maghsoudi, Mojtaba Yamani, Muosa Hosseini
    Introduction

    Karst terrains play an important role in the lives of its inhabitants, and especially in dry and semi-arid countries, they are very important in providing water resources. According to UNESCO's research, karst aquifers are the most important and safe sources of drinking water in the world (Auerli, 2010:6). It seems that in the near future, due to the pollution of non-karstic water resources, as a result of human activities, this amount will increase. Karst morphology plays a very important role in evaluating the sensitivity of karst aquifers. Karstic water resources are the most important source of water supply in Kermanshah province. Due to the characteristics of karstic zones in this area, these resources are very sensitive to environmental changes. Therefore, identifying the karst landforms, observing and analyzing them are methods that cannot be separated from the complex examination of karst zones. Karstic aquifers in the Shahu area feed on many rivers and wetlands in Kermanshah. In addition, local communities around the water use aquifers for drinking and farming purposes. Therefore, based on these facts, it is very important to provide maps that determine the extent of Karst development in these areas.

    Material and methods

    This research is based on field techniques, tools and libraries. The main data of the research include a digital model of height of 12.5 meters from the US Geological Survey, geological maps of 1: 100000, land use map from Kermanshah County Governor's Planning and Design office. In this research, firstly, Karstic Dolines were identified as the most transformed Karstic Landform in the study area using the CLC method and were validated using field studies. The Dolines distribution map was prepared. In order to investigate the relationship between each of the factors affecting the karst evolution in Shaho area, the maps of each of the effective factors with the Dolines distribution map were overlapped in the ARC Gis software, and the weight of each class of factors influencing karst evolution using the Evidential belief function was gained. A generalized nonparametric analytic collective model is an extension of linear models to generalizations (Hastie & Tibshirani, 1990). In the generalized additive model unlike the linear regression model, data is allowed to determine the shape of the response curve.

    Results and discussion

    The results of the slope factor analysis indicate that the maximum weight of Dolines produced in the Shaho area is 0-5% slope, so that 61% of the karstic dolines in this class are in the high slopes. The highest amount of Dolines is in the northern slope direction. Surveying the results of the region's mineralogy units show that the highest weight obtained from the confidence level of 0.996 is related to the Bisotun massive limestone formation, which includes most of karstic dolines. Land use results show that the most of the karstic Dolines were in the good rangeland (0.45), medium rangeland (0.48) and semi-massive forests(0.7). The relationship between the Dolines and the distance from the drainage show that the highest weight (0.63) of Dolines was observed in the distance of 100-200 meters from the drainage. The area of the Karst transformation classes is presented using the aggregated general model in Figure 1. The results indicate that 27 percent of the region is in a high level of transformation. The generalized additive model show that among the ten factors used in the model, lithology, slope, distance from fault, rainfall, altitude, distance from the waterway, land use and aspect, respectively, were significant in karst development. The coefficient of explanation for the generalized model was 0.74 for functional factors. Finally, the mapping of the Karst developement in Shaho area was evaluated using the ROC curve and its curved surface.
    Fig1. The area of the Karst evolution zones in the Shahu area (km2)

    Conclusion

    The results of validation show that the accuracy of the generalized nonparametric analytic collective model with the sub-curvature level is 0.798 is very good. The results of the model's prioritization indicate that the significance of lithology, precipitation, slope and tectonic factors was more than other factors in the Karst evolution in Shaho area. The results showed that the highest degree of karst evolution is in the low slope of 0-5%, low distance from the streams and the fault and the northern direction of slopes. The extent of karst evolution in Shahu area is higher in good rangelands. As the solubility of calcareous rocks increases with the degree of purity in the karst process, hence the high thickness and high purity of Bisetoon limeston in the Shaho region provide a good lithology for Karst development in this region. Favorable climatic conditions are not currently available for the development of Karst in this region. just at high altitudes above 2500 meters can be see the effects of the Karst evolution. The variation of karst landforms in this area is very high and therefore it is necessary to determine how using of this resources and appropriate protective measures prepared.

    Keywords: Karst Evolution, doline, Data mining, shahu
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  • دکتر مجتبی یمانی
    دکتر مجتبی یمانی
    استاد تمام ژئومورفولوژی، گروه جغرافیای طبیعی، دانشگاه تهران، تهران، ایران
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