نشریه کواترنری ایران
پیاپی 9 (بهار 1396)

Quaternary is part of the history of the Earth's development, which lasted two million years.
Quaternary sediments are of great importance as human's activities bed, and it is important to study these sediments and requires a comprehensive studies in this field. In general in Iran the quaternary sediment is alluvial fan.The aim of this research is to investigate the sub - surface geological structure of quaternary alluvial deposits in a part of Tehran and Karaj plain by descriptive - analytical method and using geophysical data using geoelectric method.
Methodology In this research, 551 vertical electric sondaj with Schlumberger arrangement in the direction of 29 profiles with the direction of southwest - northeast have been used. Initially, based on geological conditions in plain of Tehran and Karaj, the boundary layer of alluvial and bedrock, using electrical resistance values were determined. In the next step, the profiles were Separated according to the genus of the layer, then they aligned with the main navigation lines in the plain, and each of the points, in addition to the positions x, y, had a height. Finally, a map showing the topography of the bedrock was produced. For interpretation, geological maps, geomorphology, Sediments iso thickness and piezometric maps were used.
Results and discussion According to the produced map, two major ditches in the study area were observed: one of Syncline that started from Mahdasht and extends to the end of the plain, and the other Syncline end of the southeast of Tehran plain. In relation to these deformations, two hypotheses are: The first hypothesis: It seems that the existence of a syncline between the Shoor and Karaj rivers is the primary route of the Shoor River, and the initial route of the Shoor river has probably crossed the south of Mallard and the margin of the Karaj alluvial fan. Second hypothesis: It seems that with regard to the northwest slope to the south - east of Tehran's plain, underground water is gathered at its extreme point in the south - east of Tehran, and these waters leave their only way out of the way to the Qarchak of Varamin. The first hypothesis was proved with regard to the specific strength of the profiles, surface geomorphology, and geological and tectonic data Special resistance numbers in the Syncline indicate that this numbers are very low in depth and is added to these numbers on the surface. Surface morphology shows different levels of Alluvial fan in the studied area. Geological maps also show that the Shoor River passes from the Miocene formations and the Karaj River passes through the Eocene formations. The second hypothesis was analyzed by applying the map of the iso thickness of the sediment, bedrock topography and piezometric maps. Iso Thickness maps, indicate that sediments at the end of the plain, In other words, at the end of the hole, have a high thickness. The topography of the bedrock shows well the end holes. Also, piezometric maps show an increase in the aquifer level at the bottom of the plain.
Conclusion The results of the research show that the Karaj River sedimentation in the Mahdasht area has led the Shoor River to be driven to the southern part and the fault building of the area facilitates this change. In other words, the river of the river has a north-south transition. In the final stage, the Karaj River, with a sedimentation at the surface of the cone, has caused the surface of the cone to rise. The rising of the convex surface caused frequent channel movements to the southeast, and the large and present cones of Karaj in the area of Shahriar Qods were caused by these displacements.Concerning the second hypothesis, the results indicate that groundwater is gathered in the south-east hole of Tehran. These waters are limited by surrounding heights, are drained through a pass way whose gradient towards Qarchak of Varamin, and the pressure caused by the movement of the groundwater of the Jajrud alluvial fan facilitates this movement. That is why in recent years we have witnessed rising basin water levels in the Qarchak area of Varamin. The presence of plenty of abuses in recent years has shown this.

Quaternary, environmental conditions and its evidences has attracted researchers’ attention around the world. Although, more than half of area of Iran country has been covered by quaternary deposits, but there is a little knowledge about the events of the period in Iran. In according to, Geomorphological evidences of glaciers are one of the most specified evidences of quaternary climate changes in Iran. The evidence, in central of Iran with present warm and dry climate, represents more accurate changes in morphoclimatic systems and also morphogenetic and morphodynamic systems. Studying of Glacial evidences and the limit of their developments in the mountain regions of Iran is the best indicator for identifying the boundary of morphoclimatic and morphodynamic in quaternary. The main goal of the study is to investigate the scope of development of morphoclimatic and morphodynamic regions of glaciers and sub-glaciers in the past in the Ebrahimabad Plain. The area has located in the North-west of Mehriz city in the slope of Shirkuh Mountain along 31° 18´ to 31° 30´ of northern latitudes and 54° 14´ to 54°25´ of eastern longitudes. The range of elevation in the region is between 1600 meters in the output point of the basin and 4100 meters in the peaks of mountains. Primary studding show some landform which has created by glaciers such as cirques, U form valleys, and erratic stones. In the researches, we have tried to study the landforms in details.
Material and methods This research has been performed on basis of field studies and direct observation of glacial landforms. But, we studied topographical maps (1/50000), geological maps (1/100000), DEM with resolution 20 meters, and also aerial photographs, at first. The resulted information of the maps controlled with GPS System in the field. Then, we measured some boulders and evaluated the glacial landforms that have been determined on the map. For example, we determined glacial cirques and valleys using contour lines at first. Then, in the field we tested determined landforms. Also, according to geological map and climatic data we investigated the effects of lithology and climate condition on the landforms. Finally, according to erratic stones, snowline, and another glacial and sub-glacial landforms, we reconstructed past morphoclimatic and morphodynamic boundaries and drew their maps using geographical information system and surfer.
Results and discussion Observation of the different maps and also landforms in the field showed that glaciers dominated in the study area in the Pleistocene period. Therefore, we could observed evidences of two major erosional processes of glaciers includes deposition and abrasive processes. Deposition processes observed in the region are moraines, tills and erratic stones; and the abrasive process are broad valley and cirques as following: ◦abrasive evidences
-Cirques: using topographical map and its contours characteristics we marked cirques on the map. Cirques appear on the map with stretched contours as sinusoidal form. In according, we define 10 cirques, and then checked them on the field using GPS system. More of them have laid between 2050 to 2550 meters.
-Glacial valley: A valley carved by glaciers is normally U-shaped. The valley becomes visible upon the recession of the glacier that forms it. Glacier valleys are the biggest abrasive forms glacier in mountain regions that become broad towards peak. U-shaped valleys present in many parts of the world and are characteristic features of mountain glaciation. In the three sub-catchment of the region there are typically U shaped valleys. The width of some of them reach to 300 meters. They are wider in the metamorphic stones. Stone terraces are visible in parts of the valleys. Locating the erratic stones in three different place shows that the glacier tongue may have regressed in three time periods.
◦Depositional evidences
-Erratic stones or frontal moraines: An erratic stone is a boulder is carried and deposited by a glacial tongue that differs from minerals and type than the bedrock or native rock to the area in which it have remained. Erratic stones are useful indicator for showing of progressing of former ice flows. Errtics in the Ebrahimabad plain have located in the three height includes 1600, 1700 and 1800 meters. The diameter of some of them when entering the plain reach to more than 10 meters with more than 10 tones.
Conclusion In according the geomorphological evidences of glaciers and present climate data, it was found that glaciers in the Pleistocene age has extended above 2200 meters heights. From this line to the 1600 meters had been covered by preglacier system. Lower than had been affected by fluvial and pluvial systems.Different evidences of all systems has remained at present time especially evidences of glacial morphoclimatic system. However, past morphoclimatic systems changed at now and has been replaced by preglacier morphogenetic systems (above 3000 meters), fluvial system (between 1800-3000 meters) and pedimentation (below 1800 meters).

In general, loess sediment are one of the most widespread form of eolian sediment. Over the past three decades, studies on global change from loess stratigraphy have made remarkable achievements based on Aeolian deposits over the world. Surprisingly little direct evidence exists documenting the continuous and progressive effects of Quaternary climate changes on terrestrial landscapes across Iran and other areas around the world. These sediments are usually yellow but grizzly and approximately 70 to 90 percent of their formation is silt material. Iran loess often are located in northeast region. Last studies has showed that loess sediment and soil formation have correlation with cold and warm period especially with quaternary respectively. For this reason it is one of important natural archive in continental climate change. This loess capability can be used in quaternary climate change reconstruction and geomorphological change. Thick Northeast of Iran loess–paleosol sequences are among the best records of terrestrial paleoclimate changes.
A number of loesse-paleosol sequences contain a magnetic record of palaeoclimate through the Quaternary period. Anisotropy of magnetic susceptibility (AMS) was men- tioned as a good tool to determine paleocurrent or paleodirection. AMS measurements were mostly used in the investigation of igneous, metamorphic and sedimentary rocks with an increasing number of applications in Quaternary loess and paleosol studies since the end of the1980s. The sediment magnetic properties depend on the magnetic content and characteristics of the source material and post-depositional weathering/soil formation processes.
Methodology In this research Azadshar (Nowdeh Loess section) region was selected for late quaternary climate change reconstruction. This section has 23/7 thickness. Samples were selected in 10 cm intervals for magnetometry and geochemical analysis so at the end of sampling 23/7 samples were gathered from Nodeh section. Magnetic susceptibility was measured in in the Geology and Mineral Exploration laboratory. In the laboratory all samples were packed in 11 cm3 plastic cylinders for bulk magnetic measurements.
Magnetic susceptibility as well as frequency dependent susceptibility was measured using an AGICO Kappabridge instrument. In view of the geographical location of the Nowdeh Loess, this work will complement magnetic studies in northeastern of Iran and contribute to a better understanding of the relationship between loess magnetismand pedogenic intensity and hence paleoclimate. To this end, geochemical proxies of chemical weathering are included to assist the paleoclimatic interpretation of the magnetic signals. The selected samples (70 sample) were also subjected to geochemical characterization. Major elements concentrations were determined.
Result Using sensitivity of some major elements such as Al2o3, Fe2O3, CaO, MgO, SiO2 and element’s ratio such as Sr/Ba, Sr/Mn, Mn/CaO to environmental condition result to change environmental condition. Increasing of CIA and MgI indexes indicate high weathering and decreasing of them indicate weak weathering in Nowdeh section. Paleosol show high content of mentioned indexes at study area that demonstrate changing and evolution of this sediments and warm and humid weather condition. In spite of loess sediment, indicate low content of indexes that demonstrate cold and dry weather condition at Nowdeh section. So, loess and paleosols of this study formed at Glacial and interglacial period and different weather condition respectively.
Conclusion This study was conducted to investigate the composition and evaluation of magnetite susceptibility and major element geochemistry in the loess deposits and paleosols of Nowdeh section in Golestan province. Nowdeh loess-paleosol sequence is an indicator for periodic dry cool and moist-warm conditions. The loess layers are representative of dry-cool climate, whereas the paleosols are indicators of the moist-warm conditions. Formation of the studied loess and paleosols, have probably taken place in glacial and interglacial cycles with different climatic conditions, respectively. Results of this research and Antoine et al (2013) on Loess-paleosol sediments on central euro show a close relation at recent 32 Ka. In two section a climate change occur inn 30 Ka . This change has recorded by magnetic susceptibility decreasing that base on last studies show a dry and cold climate in this period. Also, magnetic susceptibility increase in 32 Ka at two section that this means appearance of warm and moist climate. However last sediment has a good relation with climate change in euro and Nodeh section but because of dating absence in last sediment deduction is not unpredictable.

In arid and semi-arid areas with limited water availability such as Iran, groundwater resources are a very important source of freshwater for domestic, agricultural, and industrial use. Regarding, the most of the plains have been salinized due to the consistent groundwater over-extraction. Since these reservoirs are located underground, monitoring of them is not easy as well as it is time-consuming and expensive.
Finney et al. (1992) developed an optimization model to control the saline water infiltration in the Jakarta Basin, Indonesia. Western and Peralta (1994) introduced an optimization model for quantitative and qualitative management of complex and nonlinear aquifers in Salt Lake Valley in Utah, USA.
Shabestar plain aquifer at north-east of the Urmia Lake is one of the fertile plains of Iran. Agriculture activities use the significant amount of groundwater in the area. Surface waters can only provide a small portion of the waters used for agricultural and industrial activities. Therefore, the life of local people is severely dependent on the groundwater whereas annually a huge amount of groundwater pumped by the farmers for irrigation peruses. Over the recent years, some parts of the aquifer located in the adjacent of the Urmia Lake is influenced by the progressive incursion of saltwater as a result of over-extraction of the groundwater. The main source of the salinity is the salt solutions which entrapped within fine-grained matrix at the southwest-end part of the plain (Immobile zone). In this research, we conducted a mathematical model to explore the qualitative and quantitative characteristics of the Shabestar aquifer using GMS (Groundwater Modeling System) processor.
Material and methods GMS is a complete program for building and simulating groundwater models (Ref). Therefore, in this research, the GMS model was applied to simulate the groundwater flow in the area. This model was originally developed by the University of Brigham Young in the late 1980s. In addition, the MT3DMS (mass-transport 3D multi-species) numerical code, as a tool that simulates solute transport in ground water, was used to evaluate the saltwater intrusion in the aquifer.
Results and Discussion To qualitatively and quantitatively investigate the Shabestar aquifer, the water-level data measured in twenty-four observation wells in 2012 were imported into GMS 7.1. The model covers the most of the Shabestar basin with 624 km2 in area. Each grid cell covered an area of 1 km2.
The optimal parameter values of the aquifer were determined after model calibration settings and verification. Simulation results show that in two parts, located in the southern and the northwest of the plain, the water table consistently declines due to the over-extraction from the groundwater. Subsequently, the MT3DMS (mass-transport 3D multi-species) numerical code that simulates solute transport in ground water was used to evaluate the saltwater intrusion. The results of the model indicate that saltwater encroachment has occurred in the southern part of the plain where the groundwater depletion is primarily caused by sustained groundwater pumping.
Conclusions To safely manage the groundwater of the area, the GMS model was conducted to quantitatively and qualitatively explore the Shabestar aquifer. The results indicated that the storage depletion is occurred in the two parts of the plain: one in the central part of the plain where the water samples were taken from the production wells show high values of electrical conductivity, and another in the northwestern part. In fact, salty solutions entrapped in the immobile zone migrate toward the production wells due to the over-extraction of groundwater. In the area, salt water intrusion can occur by two mechanisms including molecular diffusion and mechanical dispersion. The distribution of the contaminated (salinized) zone can be explored by drilling of exploration wells.
In order to prevent the progressive incursion of salt solution into the aquifer, we suggest to determine the annual safe pumping rate in the aquifer.

In almost all physiographic environments from narrow and deep valleys to vast alluvial valleys, landslides in the water flow of rivers can create natural dams. Landslide dams, as a kind of natural dams, are results of blocking the normal flow of riverswhich are created by the mass movements of hillside. Studies on different types of landslides that have formed natural dams, show that generally 50 percent of dams are caused by falling rocks and soil and landslides.
In Iran, the formation of landslide dams in relation to various factors such as topography, tectonic, geological processes and etc can be seen especially in the Zagros Mountains; Shour Dam Lake in the Lali, Khuzestan is a good example of this type of geomorphic phenomena. Above the Shour bridge and before enterance of the river to Gotvand dam, there are lake sediments in the path of Sarvand and Shour River which represents blocking narrow and deep Dozvill valley which include the river. Observing slipped stone blocks around the Dozvill valley shows occurrence of landslides, blocking the valley and formation of a dam lake in this area. Thus, a dam lake is formed and is called the Shour Lake from now; itis a dam lake caused by a landslide. This study is the first study to introduce Shour River landslide and the resulted dam lake; therefore, the aim of this study is introducing and understanding of the dynamics and the reconstruction of geomorphic evidence related to Shour dam lake landslide in Khuzestan province.
Materials and methods This study was conducted based on field studies in April 2015. Different tools such as topographic maps of 1: 25,000, geological map of 1: 100,000, satellite images IRS and TM, Google Earth images, GPS and camera have been used in different stages of the current research. First, the causes of landslides and the formation of the lake were investigated and discussed.Then, given that 3 terraces were identified within the lake, using GPS the height of the terraces to the sea level was determined and using digital elevation model in Arc GIS software environment of the lake was drawn in 3 stages. In addition, using archaeological evidence this research tries to determine the approximate age of the Shour dam lake.
Results and discussion Landslide Sa tanan is an example of the landslide occurred in the folded Zagros unit that is located on the western slopes of the mountain with the same name above the Dozvill valley with a depth of 120 m and a length of about 40 meters. Satanan Landslide which is occurred as sliding rock blocks of various sizes in the Bakhtiari conglomerate. Based on field studies the major cause of Sa tanan landslide is trenching for establishing the communication path andica- Lali, dissolution based erosion of Bakhtiari conglomerate, digging the base of Bakhtiari conglomerate as a deep valley created by shour River and crossing Lali- Andica through the study area.
After the occurrence of the landslide, stone blocks of the western edge of the valley which some of them are height up to 2 to 3 meters, fell into the valley and because of the low width of the valley they blocked the path of the river. After the closure of the valley, Shour river water and Sarvand seasonal river accumulated behind the sliding dam and created the Shour dam Lake. Since surrounding the river is filled with tall mountains;so, after filling the lake andin the lowest elevation of lake(293 meters above sea level) and on the valley filled by thelandslide that used to be the path of the river before the occurrence of the landslides, the lake overflowed and discharged.
Reconstruction of various stages of formation of the lake on the remains of the lake sediments shows that the highest level of sediments of the first terraces can be seen at an altitude of 280 meters, second terraces at an altitude of 270 meters and the third terraces at an altitude of 260 meters above sea level. As a result, Shour Lake has been formed in three stages in whichthe first terraces is related to the largest lake with an area of approximately 4 square kilometers and thethird terrace is related to the smallest lake. It should be noted that due to the low height of Sarvand River (260 meters above sea level) in the eastern parts of the valley and before joining the Shour River and also in the flow direction of the river, a small dam lake has been created.
Locating the remains of the Togheseh historic bridge or Dozvill belonged to the Sassani era (250 to 650 AD) and on the valley and lake sediments remains, the possibility that the bridge after an overflow and drain the lake has been destroyed. Therefore, the probability of the occurrence of the landslides and the formation of the lake has been in the same timeframe(250 to 650 AD).
Conclusion Shour dam Lake in the Zagros Mountain is an example of dam lakes that the reason for its formation, occurrence ofLandslides has been in the path river. The results show that because of the low width of the Dozvill valley and the largeness of the sliding parts as stone blocks, Dozvill Valley is blocked and the Shour Lake has been formed behind it. Because of the remains of the lake sedimentary terraces, Shour Lake has been formed in 3 steps and the Sarvand Lake in the Sarvand River has been formed in one step and at the same time simultaneously with the first stage of the Sour Lake.
According to the remains of a historic bridge (which has been built in Sasanian dynasty) on the Dozvill Valley and also the tear of the lake named Dozvill bridge (Togheseh),probably the creation and discharging of the lake is back to the Sasanian (250 to 650 AD) era.

Iran has been extensively studied over the last decades because its territory offers the rare opportunity to observe and quantify how the convergence between two plates Arabia and Eurasia has been accommodated from its onset to its present-day continuation, i.e., continental collision within Iran. Additionally, Iran is the site of frequent devastating earthquakes, and it is thus of critical importance to understand how those earthquakes emerge from the overall tectonics that affects the Iranian territory. All principal seismogenic faults in eastern Iran are known and their recent to current activity is not in dispute. Abiz fault is one of most active fault in Iran. It is plausible that at present the region is experiencing a temporal clustering of large magnitude earthquakes, just as the Dasht-e-Bayaz and the Abiz faults in northern and northeastern Lut Block. The earthquake took place on the right-lateral Abiz fault. The surface trace on the ground was measured at 125km for a horizontal displacement of 2.3m and a vertical one of 0.9 so a total one of 3m. The rupture length can be considered as the greatest one in the entire earthquake database done here. Nevertheless, the magnitude and the displacements are not the greatest one. The magnitude was reported as 7.3. Previous earthquakes in 1936 and 1979 occurred on the fault but did not break more than 2 segments each time. One of the major challenges in assessing potential seismic hazards is to reliably identify regions of preferred upper crustal deformation. Landform morphometrics and the respective tectonomorphic indices can be used as basic reconnaissance tools of tectonic activity which can indicate areas at risk. The qualitative and quantitative descriptions of landform development are used to identify areas dominated by rapid tectonic deformation or erosion on a local scale. In this paper, the relative active tectonic of the Abiz fault has been discussed according to the geomorphic indices using ArcGIS software. Measured indices are stream length-gradient index (SL), ratio of valley floor width to valley height ratio (Vf), Asymmetry factor (AF), index of drainage basin shape (Bs), Hypsometric curve (HC), Hypsometric integral (Hi), River sinuosity index (S), index of mountain front sinuosity (Smf). The fast evolution of digital elevation models (DEM) provides an ideal base for remotely sensed morphotectonic studies of large areas using Geographical Information Systems (GIS). However, a manual extraction of the above mentioned morphologic parameters may be tedious and very time consuming. Moreover, basic GIS software suites do not provide the necessary built-in functions. Therefore, we present a newly developed, Python based, ESRI ArcGIS compatible tool and stand-alone script, the Morpho Tool. This tool facilitates an automated extraction of the Vf-ratio and the Hc-factor data for large regions. Other factors was calculated manually. Using a digital elevation raster and watershed polygon files as input, the tool provides output in the form of several ArcGIS data tables and shape files, ideal for further data manipulation and computation. This coding enables an easy application among the ArcGIS user community and code conversion to earlier ArcGIS versions. As basic data set we use a freely available 90 m resolution Shuttle Radar Topography Mission (SRTM) DEM of a 800 x 300 km large area of the study area. Using this DEM, we perform several preprocessing tasks using ArcGIS (ESRI), including the ArcHydro extension. These preprocessing tasks include the detection and removal of cells with undefined drainage values (sink cells). Next, watershed areas are delineated by stream flow analysis, along selected mountain fronts, and stored as a polygon shape file. To enable proper distance measurements, all initial files, the watershed shape file and DEM of the study area, are converted to the projected coordinate system WGS 1984 Zone 40S. Using the result of indices, index of relative active tectonic (IRAT) calculated as well. The results show that the Abiz fault relative tectonic activity index falls into three group. From Southeast to the Northwest: they are a) the areas between North of Zeidan to South West of Ahangaran, b) West of Hajiabad to South Nodeh and c) East of Esfad to East of Fandokht. The lowest IRAT values are located in Ardekul and Kalshur. Because of flat topography in Kalshir area, it’s not possible to sense some of morphotectonical indices, so the numeric values are low.

Quaternary basalts are one of the last signs of magmatism in Iran, some of which are related to deep fractures and active faults in the Quaternary. Quaternary basalts of Tabas are very important due to their high expansion and location in eastern Iran, and are located 140 km south east of Tabas city and according to the proposed divisions are part of the Lut zone. The aim of this study was to investigate the petrogenesis of these basalts and determine the tectonomagmatic environment of the region, in which the role of the great Nayband fault should be considered. The great Nayband fault is one of the deep and large fractures in Iran's general building, which is about 500 kilometers long and extends to the Bam city. The operation of this fault is straight and displaces Quaternary sediments up to 20 meters.
More than 180 thin sections were prepared and their petrographic studies were carried out. Then 30 samples were selected and analyzed by X-ray fluorescence (XRF) method for 32 main and minor elements. Four samples from the basalts of the study area were selected and at the University of Carleton, Canada, radiogenic isotopic analysis was performed for Sr-Nd isotopes, then the lithological and tectonomagmatic diagrams were drawn.
Most of the basalts are black in color and a little red in the dark brown color, indicating their oxidation. The samples are aphanithic and no minerals can be detected. Microscopically, the texture of these rocks are porphyry with microlithic and sometimes microgranular and some samples also have a porphyric texture with a glass microlithic mesostar. phenocrysts are olivine, clinopyroxene augite and plagioclase with a labradorite compound. . Some samples do not have phenocryst. Phenocrysts vary from about 5 to 20 percent. Magmatic series of these rocks are often alkaline and some of them are sub alkaline. The young basaltic rocks of the Tabas region are derived from an alkaline magma, and this magma is contaminated by crust material on its ascent with different intensities, and where this contamination has been intensified, magma has found the characteristics of sub alkaline. In the tectonic environment, the basalts of the region are within the continental plate. Moho depth along the Nayband fault has the lowest value in Iran's plateau. The decrease in pressure along the fault, especially in areas with new sub-divisions, causes the formation and rise of magma, probably repeated injections of new and hot melt materials have been done in the magmatic chamber. The magma began to differentiate and crystallize in the magmatic chamber and then climb upward along the faults and minor fractures of the Nayband great and has been impregnated with silica stones along its path and its chemical composition has changed a bit ,after passing through the crust, magma erupted on the surface of the earth and became cold and crystallized. The tectonic studies of the area indicate the presence of the Nayband fault during the quaternary period, there are several springs along the Nayband fault, some of which are hot springs, and the most important is the hot spring of Dige Rostam, which itself indicates the depth of this fault.
The Nayband fault zone is a straight-right fault whose displacement is estimated to be 50 to 100 kilometers. Signs of activity of Nayband fault during Quaternary¡ presence of spa springs along the fault zone, dikes of volcanic materials in alluvial deposits, Presence of fault precipitations in alluvial deposits, Channel deviation along fault stretch, The earthquake of 1979, Tabas, which occurred due to the activity of one of the branches of this fault.
At the same time as the tension is applied to the northeastern direction, Nayband fault begins to move with the right movement. The continuation of this movement in the fault leads to the branching of the flap in the lateral sections of this fault to be split into the Parvade block, the branches and move dislocation slip on the fault Nayband to amend. The movement of the Tabas block to the west or southwest has created an expansion zone in the south-east of the Tabas plain and the quaternary basaltic eruption.
The south-east bases of Tabas to Quaternary, located in the Lut zone, were part of the eastern volcanism of Iran, which erupted in the vicinity of the large and active fault of Nayband . According to geochemical studies, these basalts are part of the alkaline sodic series, some of which show sub alkaline properties. The origin of the primary magma from the fertile layer of the upper mantle, which was followed by the process of separation and normal crystallization, with the presence of phenocrysts of the various indicating the severity of separation of magma before the eruption, which was accompanied by repeatedly hot and fresh injections into the magmatic chamber. Basaltic magma has been impregnated with siliceous rocks during the ascent to the surface of the earth and erupted, and its chemical composition has changed slightly, resulting in sub alkaline properties. Regarding field studies and tectonomagmatic diagrams, Tabas basalts are part of the continental basalts that erupted due to the activity and of the major fault of Nayband and its lateral branches in the early quaternary, indicating the activation of this fault and branches during Quaternary.