Abolghasem Amir Ahmadi, Leila Goli Mokhtari, Naemi Tebar Mahnaz,
Volume 23, Issue 70 (9-2023)
Abstract
The purpose of this study was to identify evidence of late Quaternary glaciers in the northern highlands of Binalood. Topographic maps, satellite imagery and climatic data are the tools and data used in this study. Arc gis 10.4 software was used for data analysis. Quaternary glacier evidences were identified based on four types of evidences including morphic indices, climatic evidences, geomorphological evidences and laboratory indices. Using morphic indexes, the curve lines were identified on topographic maps of satellite imagery, ice-dominated areas, and the effects of 28 glacial circuses. Climatic evidence shows that not only was Quaternary at about 7 degrees cooler than the present time, but its precipitation was almost twice as high as at present. On the other hand, glacier circles, moraines, thales and glacial mounds were the most prominent geomorphologic evidence of glaciers in the Binaloud Heights. Finally, granulometric laboratory indices supplementing the evidence of glaciers have confirmed the existence of glacial sediments at the Binaloud Heights. Also, using Wright's method, the permanent snow boundary line during the reign of Binalood Heights Glaciers was estimated at 2600 m.
Mr Abazar Solgi, Dr Heidar Zarei, Dr Safar Marofi,
Volume 24, Issue 72 (3-2024)
Abstract
Different methods are used for baseflow separation, filtering method one of these methods. In this study, the filtering methods with different algorithms, inclusive One-Parameter, Two-Parameter, Three-Parameter, Lyne & Hollick, Chapman, Furey & Gupta, Eckhardt and Ewma used for daily baseflow separation of Kahman karst spring in Aleshter county. The statistical period used in this study was a period of 27 years. The Isotope content method used as the main method for baseflow separation. Samples analyzed at the Mesbah Energy Company laboratory. Each algorithm has different parameters. First the parameters of each algorithm optimized based on the isotopic content method in the water year of 2017-2018. Then the optimized parameters used for the period 27 years. At the end, using the evaluation of different critical compared to the different algorithms. The results showed that the Eckhart algorithm performs better than other algorithms. This algorithm estimated baseflow and surface water indexes, respectively 81 and 19 percent.
Dr Raoof Mostafazadeh, Dr Fariba Esfandiary, Miss Mahnaz Hamzeei, Miss Nazila Alaei,
Volume 24, Issue 72 (3-2024)
Abstract
The purpose of this study was to evaluate the temporal variations of vegetation cover of Gharesou River riparian area in Ardabil province using landscape metrics over a period of 8 years which is important for morphology assessment and river ecosystem protection planning and management. The Google Earth imagery for the years 2011, 2016, 2019 due to their live view and high resolution were used to map the Gharesou River riparian area vegetation. Correlation analysis in R environment was used to evaluate the relationship between landscape metrics in the study time period. The results showed that there is an increase in the number of patches, which showed an increase in landscape fragmentation of the riparian area vegetation. Landscape connectivity index was 91.52% to 95.49% in this region during the study period, indicating the removing small patches of vegetation communities around the river. The number of patches in the present study showed an increasing trend, which was the highest amount at 2019 year. The results of changes in the width of the Gharesou River showed that the river width in 2019 was 27.43m and 3.97 m, respectively. Comparison of river width values over the three study periods indicates an increasing trend in river widths, which may be due to the limitation of river width by human activities or the protection of river banks to protect agricultural lands against flooding effect. Also, the correlation of river width showed that the correlation between time period 2019 and 2016 was 0.63 and significant at 0.001 levels. The lowest correlation between the period 2019 and 2011 was 0.30 at 5% significant level. In conclusion, the results of changes in riparian area communities can be linked to the extension of agricultural land adjacent to the main river course.
Roghayeh Delaram, Samad Fotohi, Mohsen Hamidianpoor, Morteza Salari,
Volume 24, Issue 72 (3-2024)
Abstract
The subsidence phenomenon is considered one of the most frequent hazards occurring worldwide and imposing irreparable damages every year. This phenomenon affects the ground’s surface and its layers and causes the ground deformation. It can be referred to as a morphological phenomenon that is associated with the gradual sinking of the ground and the vertical movement of materials. Among the various methods used to study the land subsidence pattern, the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique has provided more accurate results. Therefore, this technique was used to investigate the subsidence rate in Mashhad plain from 2003 to 2010 and the Envisat ASAR (C-band) and Sentinel-1 ASAR (C-band) satellite images were employed during the year 2019. The results show that the highest subsidence rate of about 44 cm occurred in Qasem Abad and Kalateh-ye Barfi lands from 2008 to 2010. A subsidence rate of about 37 cm was also observed in the same area from 2007 to 2009. The interpolation results using piezometer well statistics show a decrease in groundwater levels in this area and confirm the accuracy of the results.
Dr Esmaiel Najafi, Dr Amir Safari, Dr Ezatoalah Ghavavati, Dr Amir Karam,
Volume 24, Issue 73 (6-2024)
Abstract
Geomorphology is related to the processes and forms of the earth's surface, and any human activity, including the construction of bridges, leads to quantitative and qualitative changes in the movement and displacement of materials and kinetic energy and affects the geomorphic system, is the concern and involvement of geomorphologists. Geomorphology, as a systematic science can also study and explain the environmental realities that have been objectified in the form of processes and forms in nature, and introduce their results and output spatially in the form of maps and models. The type of research is applied and the research method is descriptive-analytical and based on the results of the Ph.D. Thesis entitled "Geomorphological modeling of the construction of bridges in urban floodways (Case study: Tehran metropolis)". The results indicate the capability and application of geomorphology in modeling and optimal location and construction of bridges, in order to create more security and welfare of citizens, reduce costs and prevent financial and human losses due to the destruction and improper location of such structures in an urban floodway- river valleys and other natural environments. Also, this study, while enriching the literature of the field in question, has studied, explained, and conceptually modeled the role and application of geomorphology in the optimal location and construction of bridges in urban issues.
Keywords: Geomorphology, Conceptual Model, urban floodway- river valleys, Bridge Construction.
Zahra Heidari, Asadolah Heqazi, Shahram Rostaei, Siros Fakhri,
Volume 24, Issue 74 (9-2024)
Abstract
Given Iran's ongoing role in the Middle East and the constant threat of external threats, it is imperative that I take action on the critical and important steps of my country Of the measures that can prevent the occurrence of malignancies , Kermanshah region due to its geographical location and proximity to Iraq as well as its complex morphology include high mountainous lands, relatively wide valleys and plains, geological structural diversity and With the immediate approach, Identify these natural features It creates the right places With passive defense approach To establish these centers. In this research, the research tools are surveyed topographic maps, geology and satellite and aerial images of the area as well as interviews with experts identifying the effective factors in locating critical and important centers with emphasis on passive defense..And after identifying them using AHP (Multi Criteria Decision Making Models) in order to compare the criteria has been analyzed. Also according to the final map based on geomorphological factors in ARC- GIS software environment The area of optimum area for the location of critical and sensitive areas in the northern part is greater than the soothe In other words, the geomorphologic features of the region in the northern and eastern parts of the region are more favorable than those in the western and southern regions for the optimal location of sensitive and important sites.
Sayyd Morovat Eftekhari,
Volume 24, Issue 74 (9-2024)
Abstract
One of the consequences of the earthquake can be changes in the elevation levels of the unevenness in the area of occurrence. These changes at the level of the region will not be the same and the amount will be different under the influence of several factors such as: earthquake intensity, landforms, geo-material, and structure geological... The purpose of this research is to measure the geomorphometric changes caused by the earthquake of 17th February 2021 at the level of Dana County using the radar technique differential SAR Interferometry. To achieve this goal, taking into account the appropriate coverage and measurement accuracy of the Sentinel 1 radar satellite images from two image scenes related to the earthquake area for the dates before (2021.02.08) and after the earthquake (2021.02.20) from the organization's website. European Space Agency (ESA) was received, after performing the process and data analysis Differential Synthetic Aperture Radar Interferometry (D-InSAR), it was found that after the earthquake dated 2021,02,17, a part of the studied area was affected by positive elevation changes with a rise of 0.11 cm and Negative changes of -0.6 cm subsidence have been encountered. These positive changes (uplift) are more noticeable near the epicenter of the earthquake in the east of Dena, and the negative changes (subsidence) are quite evident with the Syncline Valley on which Khorasan Rivers is located. And in dealing with the faults, changing the geological structure, geo-material of the region, it has a special irregularity.
Dr Mohammad Ebrahim Afifi,
Volume 24, Issue 75 (12-2024)
Abstract
Among the natural hazards, without a doubt, the flood is known as a natural disaster. In this research, Shannon entropy model was used to prepare a flood sensitivity map. First, 34 flood watersheds were selected from Firoozabad basin, and then these 34 points were classified into two groups. With 22 points, 65 percent of the points for training and modeling, and 12 points, 35 percent of the locations that were not used in modeling were used for validation. First, a map of the status of the floods was developed and Then, 10 factors, slope, tilt, lithology, land use, NDVI, SPI, TWI, altitudes, rainfall and distances from the river were selected as flood factors in Firoozabad basin. Prioritizing the effective factors in the occurrence of flood by Shannon entropy index showed that the NDVI layers (2.03), rainfall (0.00), distance from the river (1.89), SPI (385.1), elevation classes (999 (0/19), gradient with weight (0,932), lithology (478/0), TWI (379/0), and land use (280/0), respectively (0/184) have the highest and the least impact Flood events. Based on the results of the ROC curve, the predicted surface area under the curve with 35% of the validation data is equal (91.42%) and for the success rate with 65% of the equal education data (92.53%).
Mrs Zeinab Karimi, Sir Davood Mokhtari,
Volume 24, Issue 75 (12-2024)
Abstract
Rivers are environmental forms that react strongly to changes in their bed, tectonic is the most important factor affecting morphology of the river, causing significant changes in river systems. In this study, using the digital elevation model (DEM), Geographic Information System (GIS) and Global mapper 13, we investigated the effect of tectonic activity on river systems in the eastern slopes of Mullah Daghi, southeast of Zanjan province, this The area is drained by Abhar river. Using the Digital Elevation Model (DEM) in the Arc Gis 10.2 software environment, required maps including geological maps, topography and…, Geological map of 1: 250,000 leaves of Zanjan was used to prepare the fault map. In order to achieve the research objectives, tectonic activity indicators including: are Mountain front sinuosity, basin shape, drainage density, longitudinal gradient of the river, River maze, basin asymmetry, hypersometric integral, the topographic symmetry of the basin and the width of the valley floor to the height. The combination of these indicators is achieved by the tectonic activity index (IAT). The results obtained through the Iat index indicate the activation of tectonic and neotectonic in the watershed of Ardejin and Abhar and the moderate activities in the basin of the zareh bash basin. The impacts of these activities on river systems that are different from the tectonic indexes in the studied basins, such as river meanders(main stream), coniferous formation (Ardejin watershed basin), tilt watersheds abhar and Ardejin and the shape of the basins (Basin elongation zareh bash)
Mrs Negar Mirzaii, Dr Ali Ahmadabadi, Dr Seyed Morovat Eftekhari, Mrs Elaheh Lofti,
Volume 24, Issue 75 (12-2024)
Abstract
Rivers are always vital arteries of the earth and naturally, they have a gradual and continuous development process which has undergone fundamental changes after the expansion of human settlements and urban development and they have lost some of their natural functions. Wardvard River is no exception to this. This river flows in the west of Tehran province and has been heavily affected by urban development which has undergone continuous changes in its flow path due to human interference and considering that this river flows in the access route of western cities of Tehran province, its natural and gradual evolution has been disrupted that this transformation, it has removed the river from its natural condition. In this research, the factors affecting the geomorphological quality of Wardvard River have been identified and using MQI index, it had evaluated the quality of river morphology. In this method, Wardvard River is divided into 9 study periods and the three main components of the quality of geomorphological performance, artificial structures and channel adjustment have been evaluated in the form of 28 indicators. Results show due to the urban development of Tehran and many artificial changes in the Wardvard river channel, intervals 1, 3, 4, 6, 7 have earned a score of 0.2 due to human interference and canalization of the river and it is very poorly placed on the floor.Intervals 2 and 5 have earned 0.3 points and it is placed in the weak class and intervals 8 and 9 have scored 0.6 due to the low human interference and the natural course of the river and it is placed in the middle class in terms of morphological quality.
Mr Arsalan Mehrvarz, Dr Agil Madadi, Dr Fariba Esfandyari, Mr Masoud Rahimi,
Volume 25, Issue 76 (3-2025)
Abstract
River morphology holds significant importance in the fields of geomorphology and river management and engineering. The marginal sections of rivers have consistently undergone changes in their riverbeds due to various social and economic factors. The Dare Ourt River, located in the Ardabil province, represents a permanent river that has experienced frequent floods and alterations in its channel morphology in recent periods. In this study, the Dare Ourt river was thoroughly analyzed using the Rosegen model at levels one and two. To conduct this study effectively, detaied data such as 1:2000 river topographic maps, hydrometric data, and boundary conditions from the Ardabil Regional Water Authority were collected and utilized. Furthermore, the HEC-RAS hydrodynamic model was employed to extract the primary indices of the Rosegen model with greater accuracy. The outcomes revealed that the majority of the river sections exhibit a C6c type, characterized by an alluvial substrate. Additionally, other dominant types observed within the four examined ranges include B6c, E6b, F6, and D. Field visits also confirmed a transition in the river type from C to F within range 4, which presents challenges for the reconstruction and restoration of the river in type F. As a recommendation, it is advised to implement restrictions to prevent the river from transitioning into type F.
Dr Esmaeil Najafi, Mr Abolfazl Faraji Monfared, Dr Mehdi Ahmadi,
Volume 25, Issue 76 (3-2025)
Abstract
The extent of mountainous and desert areas in Iran has caused the emergence of well-known geomorphological phenomena. Alluvial fans are landforms found in various locations. Identifying and evaluating their impacts can be valuable for natural hazard management and land use planning. In this study an attempt hs been made to evaluate the status of tectonic activities in the south of the slopes of the Kharqan mountain range in the northeast of Hamedan province. Different maps were utilized to examine the development process of alluvial fans and present evidence of tectonic activity, including the Gozal Valley, Karafs, and several smaller alluvial fans. The findings of this study revealed that tectonic activity in the Gozal Valley cone remains active, while the alluvial fans located between the Gozal Valley are inactive. Further evidence in the bed of the Gozal Valley cones suggests tectonic changes caused by fault activity, resulting in the alteration of the riverbed's drainage pattern and subsequent destruction and erosion of the surrounding areas. Additionally, changes in drainage patterns and sediment depth on the surface of alluvial fans can be attributed to tectonic activities within these fans. Geological logs illustrate both prolonged, slow periods and active periods during various geological eras in the study area. Ultimately, tectonic activity initiated with a lengthy, sluggish phase, followed by continued tectonic activities and fluctuations.
