alireza taghian

River terraces represent a history of river stratigraphy and provide valuable information for understanding the interactions of tectonics, erosion, and climate change. The high altitude of the Jajrood basin has resulted in extensive glacial remnants, especially the accumulation of moraines upstream of the basin. The extent of moraine depositions under the upstream basins of the Jajrood River is not evident in the structure of river terraces and they do not have a uniform elevation. Moreover, the relations of old glacial conditions in the sedimentary interference of terraces cannot be easily reconstructed and discriminated, and there is no regular order in the stratigraphic sequence and sedimentological conditions of the river terraces. The moraine deposition seemingly has had a major role in the differences in river terrace sequences from upstream to downstream of the study area, which calls for further investigation and is also addressed in this study. Many studies have delved into the analysis of the evolution of the river terraces. Other important areas of study include paleontology and sedimentology and their effects on the canal sustainability against flow dynamics. This study aimed to explore the climatic and neo-tectonic developments of the Jajrood River Basin and the role they have played in creating terrace sequences.

This pure research investigated the role of neo-tectonic developments and climate change on the formation and evolution of terraces in the Jajrood River Basin. The research was based on analytical calculations and reports prepared through surveys as well as remote sensing methods to examine the effects of tectonics in the area. In addition, sedimentological evidence was studied to see how climate change has affected the formation and evolution of these terraces. The primary research tools were topographic and geological maps alongside aerial photographs and satellite images. Other fieldworks such as terrace morphometry using GPS measurements and sedimentological analysis helped to add insight to the findings. Then, the data was analyzed in ArcGIS. Here, the Jajrood Canyon was divided into three sections to better examine the morphogenesis of the terraces. Next, the transverse profiles and stratigraphic sections were drawn up to investigate the sedimentary strata in each section through morphometry, and then the evolution of the terraces was analyzed and reconstructed. The tectonics were studied using radar images to determine vertical displacement through the small baseline subset (SBAS) time series. Here, 27 Sentinel-1 images were used for the period from Oct. 14, 2014, to Oct. 27, 2016. which was performed using Generic Mapping Tools (GMT) in Linux OS. After preparing the interferogram maps, a map of the displacement in the study area was generated using the SBAS method (Zhao, 2013). Moreover, changes in the climate were studied using sedimentological and stratigraphic evidence.

The research findings can be classified into two parts. First, neo-tectonics was investigated through remote sensing methods and the analysis of vertical displacement across the region. Then, the effects of these neo-tectonic processes on the genesis and evolution of terraces were examined. In the second part, the effect of climate change on terrace developments was explored using sedimentological and stratigraphic evidence. In the first part, the region's tectonics was analyzed using radar imagery. In doing so, the vertical displacement was measured using SBAS time series and 27 Sentinel-1 imagery during the period from Oct. 14, 2014, to Oct. 27, 2016. The specifications of the research images are presented in Table 1. The images were selected based on the research purpose and the baseline of the images relative to each other. The VV polarization was used for all images since co-polarizations exhibit a stronger backscatter. Some sensors have different polarizations, and images with different polarizations can inform interpretations to a great extent.After preparing the images, for measuring displacement using the SBAS method, first, the temporal and spatial baseline of the images was examined and image pairs were selected for interferogram generation (Table 2 and Figure 3), which was performed using GenericMapping Tools (GMT) in Linux OS. After preparing the interferogram maps, a map of the displacement in the study area was generated using the SBAS method. In the end, the role of morphotectonic relations in the morphogenesis (i.e., origin and development) of the terraces were examined.

These findings suggest that terraces in the Jajrood Canyon are highly heterogeneous in terms of sedimentological structures, stratigraphy, and altitude. For instance, the T3 to T1 terraces, respectively, were located 130, 90, and 80 m above the river. These terraces have also experienced three intermittent processes. These three river terraces were created through the combined effects of climate change, tectonic uplifts, and the formation of dam lakes. The results of SAR interferometry (InSAR) and fieldworks also confirm the effect of active tectonic uplift differences along the main canal. These differences reflect the differences in their morphogenetic processes. The altitude of the terraces at the Oushan River tributary (Section 1) is nearly 130 meters. However, this section's altitude downstream (near Hajiabad Village) is estimated at 90 m. This difference cannot be merely due to baseline discrepancies. Evidence indicates that a sedimentary interference originating in the lake due to a past landslide downstream of the study area (Hajiabad landslide) is the cause of the higher altitude of the terraces in this section. The terrace sequences were not the same in any of the three sections. To be more precise, there are three identifiable terrace levels in Section 1, two in Section 2, and one in Section 3. In addition to the differences in the tectonic baseline, three factors—namely climate change, moraine, and the formation of a landslide-dam lake downstream—were identified for the genetic diversity, sequence differences, and terrace sequences throughout the three sections. In addition to morphometric differences, there were great differences in the genesis of the terrace sediments. The river has contributed the most to the formation and structure of terraces and their genesis. Nevertheless, the interference of landslide-dam lake deposits, moraines, and alluvial deposits, consecutively or simultaneously, have affected particularly sections 1 and 2 through differences in flow dynamics. Meanwhile, greater uniformity can be seen upstream, particularly in the Garmābdar basin (Section 3), such that upstream terraces in this section are predominantly glacial.

By studying, the geological structure, landforms topography, pattern of drainage network systems, indicators and geomorphological evidences of each region, the performance of Active tectonics can be evaluated. The Karkas Mountain is located in the east of Isfahan and the magmatic arc of Urmieh – Dokhtar between Sannandaj and Sirjan. The purpose of this study is to investigate, evaluate and estimate Neotectonic and its effect on morphology, behavior, formation and evolution of southern catchments of Karkas heights using geomorphic morphometric indices and its adaptation to geomorphological evidence in the region.

In this study, after studying and collecting library information, preparing the required data, in the ArcGIS software environment, the area of the basins south of Karkas Heights (10 catchments) was determined and their drainage network was extracted from DEM. Using Geomorphologic indexes to evaluate the amount and intensity of Active Tectonics in the area. This Geomorphologic Indicators are the Ratio of a Circle (Re), Bifurcation ratio (Rb), Basin form (FF), Geomorphic features of the Hypsometric integral (Hi), Basin Volume Area (V/A), The topographic symmetry Factor (T), River Length-Gradient (SL), River Sinuosity (S), Mountain Front Sinuosity (Smf), Basin shape ratio (Bs), Alluvial fan Area (Af), Alluvial fan Slope (Sf). Then using the relative active tectonic index (Iat), As a model and conceptual technique the amount of tectonic activity in catchments was calculated. Finally, the morphological evidence of active tectonics in the study area was examined. DEM 90-meter of the country is surveying organization, geological map 1: 100000, topographic map 1: 50000, IRS satellite images and Google inherit the data used in this study.

Each of the quantitative characteristics of catchment basins with specific values represents a form in the catchments. The relative active tectonic index (Iat) and Geomorphological Indices show that the area is very active. The Niazmargh, Soh, Safiabad were more active than other catchment. Existence of numerous faults that are part of the Qom-Zefrah fault system is one of the geomorphological evidences in the study area. Each of the catchments in the area is affected by one or more fault systems. Quaternary faults do not exist in all catchments of the region and are seen only in the catchments of Maravand, Absenjed, Robat, Panavand, niazmargh and the border between Safiabad catchment area and niazmargh and Panavand catchments. The valleys and canals of the rivers of Maravand, Niazmargh, Soh and Kalaharood are suitable with geological structure, tectonic activities, slopes and erosion processes have different shapes. Another geomorphological evidence in the study area is alluvial fan section. The old, semi-active and active alluvial fan can be seen in Soh area. In Kalahrood catchment, the traces of old alluvial fans have been largely destroyed and only a few parts of it have been left. Tilt of the alluvial fan and displacement of the main waterway on the alluvial fan are the other effects of tectonic movements in the region.The course of rivers in the mountainous part, depending on the land structure or tectonic structure, has an almost east-west or northeast-southwest trend, but after leaving the mountain, under the influence of the northern part, it turns to the south and goes north-south. Some rivers (Soh, Kalahrood and Robat) have been diverted to the east due to the more uplifted of the northwestern part.  In the northwestern part, due to more uplift, successive alluvial fans have been formed, while in the south-eastern part no evidence of it is observed. The slope of basins and rivers in the northwestern part is more than twice their slope in the southeastern part, which can be affected by tectonic movements. The average slope of the basins in the northwestern part is 25 percent and in the southeastern part is 12.7 percent and the average slope of rivers in the northwestern part is 20.75 and in the southeastern part is 8.1 percent. In the northwestern part, the erosion power of rivers has increased so that rivers have been able to create deeper valleys (Soh and Kalahrood valleys). While in the southeastern part, the width of the valleys is usually greater than their depth. Vf is 1.7 in the northwestern part and 8 in the southeastern. The heights of Karkas and its surroundings are active in terms of seismicity, so that in the last three hundred years, about six earthquakes of more than 4 Richter were recorded, the last of which occurred in 2016 in the Habibabad basin. During a four-year period (2008-2004), 1250 earthquakes have been recorded in Isfahan seismic network (Kalahrood, Zefreh, Nain, Qarneh and Pirpir stations)). The seismicity of Qom-Zefreh fault is estimated to be about seven Richter.According to the values of geomorphic indicators and seismic data it seems that the region is tectonically active and this activity has been more intense in Maravand, Niazmargh, Soh and Kalahrood basins. The intensity of tectonic activities decreases from northwest to southeast, so the region can be divided into northwestern and southeastern in terms of activity intensity. 

The relative active tectonic index (Iat) and Geomorphic Indices show that the area is very active. The Niazmargh, Soh, Safiabad were more active than other catchment. The Iat index of catchments is 1.93 which varies from 1.2 to 2.6 in catchments. The deep River valleys (Soh, Kalahrood, Niazmorgh and Panavand), consecutive and fragmented alluvial fan (Soh and Kalahrood rivers), river terraces, diversion paths and riverbeds (Soh, Ka lahrood and Robat) and numerous faults are geomorphological evidence that confirm the characteristics of the basins are affected by tectonic movements in the region. The results of geomorphological indices and seismic data of the region show that the catchments are active in terms of tectonic activity, but the intensity of tectonic activity in the region is not the same and its amount decreases from northwest to southeast. The impact of tectonic activity in the northwestern basins has been greater than its impact in the southeast. These activities have deepened valleys, changed the course and bed, increased the slope of some rivers, increased the erosive power and fragmentation and sequencing of alluvial fans.

The sediments of the Playa Lake are sensitive indicators of local climates that any change in climate, hydrology, and sedimentary environment will cause changes in the physical and chemical properties of the sediments. These sediments create a valuable and important archive with high resolution to examine these changes in the past. One method of studying climate change during quaternary and often Holocene is the study of Sedimentology, mineralogy and sedimentary geochemistry in sedimentary cores harvested from wetlands and lakes. These studies can help to more accurately identify and re-read their past history and be used to investigate possible climate change. The Gavkhouni Playa is one of the pluvial lakes of the Plio-Quaternary depositional basins in Iran that is located in the lowlands of the Esfahan Plain, Central Iranian Plateau. Various sediments in and around Gavkhouni palya indicate the frequent alternation of formative systems during the Quaternary hot and cold phases. The history of late Pleistocene to Holocene sedimentary evolution, and paleo-geomorphology and paleogeography of the Playa were investigated in this study.

Identification of the climate changes is important for understanding the paleoenvironmental characteristics. Sedimentary evidence of the closed basins can be one of the most important methods for identifying the climatic periods and changes in the sedimentary environments. Gavkhouni Playa, as the lowland of the ZayandehRud River catchment area is located in an inter-mountainous basin in the Central Iran. This area is one of the pits separating the Sanandaj-Sirjan tectonic zone from the Central Iran, located parallel to the Zagros over thrust. A total of 16 sedimentary cores were taken from the inner part of the Gavkhouni Basin, the outer part of the basin, and the surrounding lands in order to investigate the sedimentary environments of the Gavkhouni Playa during the Late Quaternary.

The steps of this research include book studies, field works, laboratory works, data processing and then interpretation and conclusion. To investigate the paleontological climate and conditions of the sedimentary environment, 16 intact sediment cores with the mean depth of the sedimentary cores was equal to 7 m and its maximum depth was equal to 11.5 m. Sedimentary facies were identified and separated based on the sedimentary texture, type of evaporite minerals, presence of organic materials, color changes, and other microscopic components, and sampling was performed based on the changes in types of sediment and sedimentary facies. A total of 80 sediment samples were selected for granulation analysis by two methods of wet sieving for coarse-grained particles and laser particle Sizer Analysette for particles smaller than sand (Silt and Clay). Sedimentology parameters were calculated by the SediLizer software and the results were analyzed statistically by the SPSS software. Also, 3 sediment samples sent to the Marmara Research Center, Earth and Marine Sciences Research Institute in Turkey to age measurement analyzing by the radiocarbon method of organic matters.

In the studied cores, 8 major sedimentary facies identified. The facies often contains clay, silt, sand, gravel, and interstitial sediments along with vegetation and shell fossils which in most cases frequency and interference in the mentioned sediments are often seen. Changes were in particle size between clay to gravel due to process type changes, environment's energy and river input's amounts and sediment color variations concerning sedimentation conditions, presence of organic matter, pH amount, salinity and temperature variations, and drought occurrence, throughout the cores. The results of the analyses indicated the identification of eight sedimentary facies, five sedimentary environments, and two types of wind and water processes, which are effective on the sedimentation of the Gavkhouni Playa sub-surface. The major types of sediments in the Gavkhouni Playa sub-surface, mud, and sedimentary environments included the aeolian, river, deltaic, lake, and playa environments. According to the C14-AMS isotope dating analysis, sedimentation rate is about 0.4 and 0.25 mm in the western and eastern parts per year, respectively. According to dating analysis, the paleogeography of the Gavkhouni Playa and the extent of its expansion have been reconstructed at least 40,000 BP. According to the studies, about 18-40 ka BP, the Gavkhouni area has been influenced by the heavy precipitation so that, the amount of sediment load imported from the west (ZayandehRud River) has been high. The great Delta of ZayandehRud has been formed and the coarse-grained particles have been deposited in the gravel and sand sizes. Since, 11.6 -18 ka BP, along with the coastline regress, the great Delta of ZayandehRud has flowed into north of the basin. The end of Delta stretches until the center of the Playa, and sand dunes have been formed to the west of the basin. With the onset of Holocene and the increase in the temperature, it has led to an increase in the size of the aeolian sand deposits and the expansion of the playa environment until about 8.2 ka BP on the margin of the lake. Since, 4.2-8.2 ka BP, it has been accompanied by a temporary progress of the Gavkhouni Lake, and 4.2 ka BP, it has regressed again with a drought occurred about 200 years ago. The progress of the lake facies has taken place about 3.5 ka BP, after which regression has occurred and playa and aeolian facies have replaced with the lake facies. According to the type of the sediments in the Gavkhouni sub-surface, it can be said that, the conditions of the northern and eastern parts of the Gavkhouni Playa have been similar to the current conditions for at least the last 3000 years and also the conditions of the western part for at least the last thousand years. The increase in the thickness of the layers of evaporite sediments, which are mainly salt, in the upper layers of the playa indicated that the Gavkhouni Playa has become drier than before in the recent centuries.

According to the results the Gavkhouni Basin has extended to the western part of the sand dunes during the Late Pleistocene. During the Early-Middle Holocene, coastline regress and the ZayandehRud Delta progress toward the Playa have occurred in the northern part of the area. During this time, aeolian sands have spread to the Gavkhouni Playa. In the Late Holocene, semi-arid conditions have reduced the water levels, coastline regress has occurred, and playa environment has been dominated in the Gavkhouni margin. But, there were still lake conditions in the center of the Playa. Gavkhouni Playa has experienced an increase in the level and progress of the coast towards the land about 3 ka BP. The creation of arid conditions about 1000 cal BP has turned the entire Gavkhouni zone into a playa environment, and this situation has been dominated the area almost to this day.

The sediments of the Playa lake are sensitive indicators of local climates that any change in climate, hydrology, and sedimentary environment will cause changes in the physical and chemical properties of the sediments. These sediments create a valuable and important archive with high resolution to examine these changes in the past. One method of studying climate change during quaternary and often Holocene is the study of clay minerals in sedimentary cores harvested from wetlands and lakes. The study of clay minerals in these sediments can help to more accurately identify and re-read their past history and be used to determine the severity of weathering processes and also to investigate possible climate change. Clay minerals are highly efficient in hot and humid environments with high chemical decomposition, for detecting climate change, and in cold environments as a factor in identifying the source of sediments.

To perform this study, 16 sedimentary cores were harvested using a manual core drilling equipment with an average depth of 7 m and a maximum depth of 11.5 m from the sub sediments of the Gavkhoni playa and surrounding areas. The core was described based on texture, sedimentary structure, and layering characteristics, color, plant and shell remains, the type of evaporative crystals, and the relative degree of hardening of the sediments, and their chronological column was plotted. 90 samples from 9 sedimentary cores were prepared for X-ray diffraction analysis (XRD) and sent to the laboratory. Also, to extract the age of sedimentary sequences, three samples of C14-AMS bulk sedimentary materials were analyzed and calibrated with OxCal software (Bronk Ramesy, 2013) with an error range of 2 Sigma and confidence level of 95%.

The results of X-ray diffraction show that the sediments in the Gavkhoni playa in order of abundance contain clay ellite, chlorite, montmorillonite, and kaolinite deposits, respectively. They are also seen as the main minerals of quartz, calcite, feldspar, evaporative and dolomite minerals in graph peaks. According to the results of the metering analysis, the sedimentation rate in the western parts is about 0.4 mm per year and in the eastern parts is 0.25 mm per year. The clay minerals of Sepiolite, Polygorskite, and Kunzite have not been observed in sedimentary cores. These minerals are specific to the diagenetic environments, indicating no effect of very low effect of the conversion type of diagenesis in Gavkhoni playa deposits. Therefore, considering the assurance of the ineffectiveness of conversion diagenesis, it is possible to achieve long-term climate at different times. Ellite and chlorite minerals in the cores of the northern part of Playa are mainly due to the weathering of the basic masses of north Playa (koh siah) and the weathering of volcanic rocks and low-grade metamorphic rocks in the Urmia-Dokhtar zone. The presence of kaolinite and the increase of phonetic minerals, especially quartz, in the two cores of G-13 and G-11 at depths of more than 3 meters indicate the presence of high-volume river flows in the region, which indicates humid and warm climatic periods. The presence of montmorillonite and ilite in the central cores of Playa with the age of more than 25000, evokes cold and temperate conditions in the late Pleistocene era in the region. The high water period in the late Pleistocene (about 18000 years ago) is marked by the precession od shore lines to land in the G-11 core with the presence of kaolinite at depths of more than 4 m. The wet conditions have gradually decreased from about 18000 to 12000 years ago. During this period, kaolinite is replaced by montmorillonite, which indicates a decrease in rainfall compared to the previous period. The predominant minerals of the early Holocene in the Gavkhoni playa are the illite and chlorite, indicating semi-dry conditions. During this time, the Montmorillonite mineral can be observed in the G-2, G-4, G-11 and G-13 cores, which is in good agreement with the delta facies at a depth of 3 to 4 meters in the G-2 and G-4 cores. The existence of a dry period about 8000 years ago is evident by the increase in evaporative minerals, the absence of kaolinite and montmorillonite, and the spread of dune sands at a depth of about 2 to 3 meters in the cores of the western and central parts is evident. 4000 years ago, the northern cores (Zayandeh Rud estuary) showed wet conditions with the presence of montmorillonite, illite and chlorite. This situation has continued for about a thousand years, after which the conditions have become a bit drier with the increase in evaporative minerals. In general, relatively low water and dry periods can be identified by increasing the rate of evaporation and expansion of dune sands and high water and wet periods can be observed by increasing the amount of debris sands as well as kaolinite and montmorillonite minerals.

The climate of Gavkhoni region in the post-Pleistocene has been wetter than today. This situation has continued for the past 18000 years and has led to the precession of shore lines. Since then, the early Holocene (past 12000 years) has been marked by a gradual decline in coastal humidity and backwash. With the onset of the Holocene, dry conditions gradually developed and peaked about 8000 years ago. In the middle and late Holocene, suitable humidity conditions have been gradually created and a water environment has been formed in the northern part of Playa due to the entrance of Zayandeh rud river. This situation was dominated by semi-arid conditions about a thousand years ago, which was accompanied by an increase in the evaporative deposits.

Application of morphometric indices in optimization of landslide susceptibility zonation maps using probabilistic As a geomorphic hazard, landslide incurs great deals of financial damages and casualties every year, and directly and/or indirectly contributes to large economic costs in different areas. Given that numerous factors contribute to the occurrence of a landslide, in order to prepare more accurate zonation maps, it is necessary to use more information layers and evaluate various factors that can possibly contribute to the occurrence of the event before adopting the existing models to zonation the susceptibility map. This phenomenon is a natural hazard which is affected by the land surface shape (morphology). As such, when it comes to susceptibility analysis of landslides in a particular area, not only common factors in zonation, but also morphometric features of ground surface are important and should be evaluated. Geomorphometric indices, which together comprise the so-called morphotectonic framework, can be used in studies on many geomorphologic events and natural hazards. These indices express quantitatively characteristics of hillsides which are susceptible to landslide. In this research, a total of 18 factors contributing to the occurrence of landslides in Fahlian watershed were identified and evaluated; these included slope, slope aspect, slope length, altitude, distance to fault, distance to river, precipitation, litology, landuse, general curvature, Plan curvature, profile curvature, Normalized Difference Vegetation Index (NVDI), topographic position index (TPI), Length and Slope Factor (LSF), Terrain Ruggedness Index (TRI), Stream Power Index(SPI), and topographic wetness index (TWI). In order to prepare layers of the effective factors, in addition to 1:100,000 geological maps, 1:50,000 topographic maps, digital elevation model (DEM: ASTER), satellite images, and aerial photographs, ArcGIS, Global Mapper, Surfer, and ENVI 4.5 software packages were utilized. Given the focus of this research on the application of morphometric indices to optimize zonation map of susceptibility to landslide, the indices were extracted. Land surface characteristics (i.e. morphometric, hydrologic, and climatic properties, etc.) and land features (watersheds, stream networks, landforms, etc.) were extracted using digital models of ground surface (DEM) and parameterization software. Subsequently, using Dempster-Shafer probabilistic models, evidence of weight, and the morphometric indices, zonation map of susceptibility to landslide was prepared for Fahlian River watershed. Finally, using receiver operating characteristics(ROC), both models were validated. Based on the weights related to the role of each unit of factor layers and their order of priority and importance in the occurrence of landslide, and upon combining factor maps and landslide distribution maps and calculating the weight of each level based on the relationships related to the Dempster-Shafer model in GIS environment, it was found that, with a belief function weight of 0.87 and minimum disbelief weight, slope > 40% imposes the largest contributions into the occurrence of landslide across the watershed. At lower slopes, other forces such as the friction between soil particles and other hillside material usually dominate over driving forces such as gravity. In contrast, on highly sloping hillsides, due to the dominance of shear stress over resisting force, one may end up with increased probability of the occurrence of a landslide. Moreover, based on the obtained results, with a belief weight of 0.77, TRI > 14 was the second most effective factor on the occurrence of landslides across the studied watershed. It was further found that, Stream Power Index < 1.2, concave curvatures, precipitation < 750 mm/year, TPI < -4.2, profile curvature of 0.3 – 4.2, TWI of -1.5 to 2.5, forest lands, surface curvature of -5 to -2.99, distance to fault of 0 to 500 and Pabdeh – Gurpi and formation (with belief function values of 0.68, 0.63, 0.60, 0.57, 0.49, 0.49, 0.47, 0.46, 0.38, and 0.37, respectively) imposed large contributions into regional landslides.
According to the evidence of weight model, the class of TRI >14 (final weight: 2939.32) was found to the most effective factor on the occurrence of landslide across the region. Following a similar trend of reasoning, the class of slopes higher than 40% (final weight: 2611.21) was the second most important factor, which are in agreement with the results of Javadi et al. (2014) and Teymoori-Yanseri et al. (2017). Moreover, in their research, Pourghasemi et al. (2011) referred to the slope as the second most important factor contributing to the occurrence of landslide. In this model, NVDI > 0.6 (final weight: 400.60) is identified as the third most important factor. Following the land use, Stream Power Index > 1.2, TPI < -4.2, TRI of 7 – 14, profile curvature of 0.1 – 0.3, NVDI of 04 – 0.6, precipitation > 750 mm, and Pabdeh-Gurpi Formation imposed the largest impacts (sorted in the order of effectiveness, with final weights of 2037.60, 1925.99, 1803.48, 1793.34, 1722.40, 1494.60, and 1340.28, respectively). Final results of the present research showed that, in both of the models, slopes higher than 40% and TRI > 14 exhibited the highest weights and played the most significant roles in the occurrence of landslide across the region. Moreover, based on the obtained results, 82.59% of the landslides across the watershed in an area of 547.82 hectare had occurred in postures. Based on the results of Dempster-Shafer model, very low, low, intermediate, high, and very high susceptibility classes covered 23.85% (961.34 km2), 31.82% (1282.49 km2), 21.72% (875.63 km2), 16.41% (661.45 km2), and 6.20% (249.97 km2) of the entire region, respectively.
Moreover, the results obtained from the evidence of wight model model shows that 25.29% (1019.59 km2), 30.98% (1248.82 km2), 21.28% (857.64 km2), 15.68% (631.93 km2), and 6.77% (272.90 km2) of the entire susceptibility zonation map are composed of zones of very low, low, intermediate, high, and very high susceptibility, respectively. Results of evaluating the models using ROC showed that, the Dempster-Shafer model provides higher prediction accuracy (0.79) than the evidence of weight model (0.76). Considering quantitative results of validation, the combination of Dempster-Shafer model with morphometric indices is herein introduced as an appropriate model for zonation susceptibility to landslide.
Keywords: landslide, Dempster-Shafer model, evidence of wight model, morphometry, Fahlian Watershed.

Landslide is a natural disaster resulted from geomorphologic, hydrologic, and geologic conditions along with human factors. As of present, many pieces of research have been performed to achieve such a purpose based on various models. However, many of such works have failed to provide satisfactory results due to failure to consider surface landform, so that limitations have been encountered when it came to the application of their findings. This highlights the necessity of using novel methods based on quantitative criteria of landform to identify the zones susceptible to landslide, so as to conduct proper planning for such zones. In this respect, morphometric parameters can represent landform characteristics of the hillsides susceptible to landslide. Moreover, in tectonically active areas, instability of the hillsides can be observed in the form of various types of landslide. This shows that, when it comes to the assessment of landslides, one should further consider neotectonic activities by means of geomorphologic indices.
In the present research, a total of 20 effective factors were used to assess accuracy of a landslide susceptibility zoning map; the factors include 14 conventional factors along with 6 geomorphometric factors. For this purpose, firstly, independence of the factors affecting the landslide was analyzed by performing Multicollinearity reach tests. To this end, two important indices, namely tolerance (TOL) and variance inflation factor (VIF), were used to undertake multi-directional reach test. These two indices are commonly used when running generalized linear models for analyzing the relationship between independent variables or conducting multi-directional reach test. Even though no consistent principle is presented for determining thresholds of these two indices (VIF and TOL) in multi-directional analysis and estimation of the factors affecting landslide, but records of the research works performed on this topic show that, multiple-correlation problem will arise (i.e. the data or independent variables are not correlated at all) if the value of VIF is smaller than 5 or 10 and the value of TOL is higher than 0.1 or 0.2. Moreover, in order to assess the correlation between the landslide and the selected factors, the weights obtained from the confidence factor (CF) model were used in the form of bivariate statistical analyses. The weights calculated by this model were further employed to prepare factorial maps and convert them into binary maps (wherein the levels with negative and positive weights were represented by 0 and 1, respectively) to be introduced into the conditional independence test. Continuing with the research, once finished with entering the weights obtained from the CF to the logistic regression model, the model coefficients were extracted. Using the obtained weights, the model was run to prepare a landslide susceptibility zoning map following either of two approaches, i.e. with and without considering geomorphologic indices along with other effective factors. Finally, Receiver Operating Characteristic (ROC) curve was used to validate, assess, and compare the maps obtained via either of the two approaches.
Based on the results of multiple correlation test, no correlation was obtained between the independent factors with VIF value of at most 3.559 and TOL values of at least 0.253. All of the values of VIF of the independent factors were lower than the critical value (5 or 10), while all of the values of TOL of the independent factors were higher than the calculated value by the critical theory. Maximum and minimum values of VIF were found to be 3.559 and 1.101, respectively, and the corresponding values to TOL were 0.253 and 0.895, respectively, which referred to the land roughness and slope direction, respectively.
The results obtained from the CF model showed that, the land roughness values exceeding 14 followed by slopes exceeding 40% possess the largest CF weights, among other levels of the considered factors, while waterway densities ranging between 0 and 10 and precipitations lower than 550 mm exhibited the lowest CF weights. According to the results obtained from the logistic regression model, the slope, NDVI, and slope direction exhibited the highest correlation coefficients, making them the best predictors of landslide occurrence in the region. Combing the weighted maps, zoning maps were prepared via the two approaches. Accordingly, 17.06% and 8.27% of the area understudy were identified as very highly susceptible to landslide, for the cases with and without considering the effects of geomorphologic factors, respectively. In addition, based on the results of ROC, the area under the curve was evaluated as 0.88 and 0.82 for the cases with and without considering the effects of geomorphologic factors, respectively. This confirms higher efficiency of the models into which geomorphologic factors are incorporated along with other common parameters considered in landslide susceptibility zoning.

Medical geography is one of the sciences that geography topics related to health and disease using quantitative and qualitative methods is studied cartography, statistical analysis, one of the diseases that are prevalent today gastric cancer.
This disease worldwide, and more equal distribution in Southeast Asia can be seen, the rate of future generations of immigrants to learn the risk increases that may be due to the impact of environmental pollution on the incidence of this disease. The need for special attention to environmental causes increased prevalence of disease in the world, especially Iran confirmed.
In this study, two types of patients with gastric cancer and nitrate in drinking water is used,for Mapping information for mapping and GIS software was used to analyze the statistical software SPSS and EXCEL.
Findings: The main focus of the city in the province of Frieden, the city Semirom and Ferydonshahr. The comparison of these centers are centers of nitrate in drinking water (nitrate areas between 45 to 20 Mg/l) showed These areas are based on the correlation and regression coefficients are positive, with R =42% and P = 0.05 , respectively. The disease is more prevalent in people over 75 years and men.
According to the results obtained in this study and studies Nitrate in drinking water can cause an increased risk of gastric cancer, especially in the older people.

Brain infarction after trauma is uncommon. Injury of the carotid and vertebrobasilar arteries can cause brain infarction due to occlusion of brain blood flow.

Emergency medical service (EMS) brought a 4-year-old girl involved in a car accident to the emergency room. She had had seizure controlled by diazepam. She was unconscious and her Glasgow coma scale (GCS) score was eight. Early vital signs were stable. Her first brain CT scan showed a subdural hematoma (SDH). One day after admission to ICU, her GCS decreased to five; hence, a control brain CT was performed. The brain CT scan showed a brain infarction. Six days after admission, her status worsened and her GCS dropped to three and her pupils became dilated bilaterally and unresponsive to light; she was pronounced dead.

We present an uncommon case of posttraumatic brain infarction and synchronous SDH.

Geomorphological indicators are usefull and confident implements in tectonical activities assessment. Using these indices one can identify regions that experienced rapid or gradual tectonic activities. The study area locates in the middle of Isfahan province. Karkas mountain is situated in Oroomieh - Dokhtar zone. The orogeny still continue to act in Iran and influence this area. The goal of this study is to assess active tectonic in Karkas slopes. In this study, aerial photographs, landsat ETM data and topographic and geological maps in various scales were used. Geomorphological indicators such as mountion front sinuosity, proportion of the valley width to its height, the indicator of stream length –gradient, drainge asymmetry factor have been used to estimate the rate of tectonic activity in the slopes of Karkas. The analysis and investigation of these parameters and indices showed that this area is tectonically active, but theses forces are stronger in the northeast slopes than the southwest shopes.