Quaternary Journal of Iran

Abstract With the development of the drilling industry in the country since the early 1930 and the use of deep well drilling technology to exploit groundwater resources, the balance of renewable water usage has been disrupted, leading to numerous social conflicts. Since the damages caused by such exploitation become apparent later, its irreversible effects may persist for decades or even centuries. This can result in the migration of residents, abandonment of investments, and ultimately, desertification. Unfortunately, in densely populated provinces of the country, reliance on groundwater resources for water supply has led to land subsidence. Despite favorable climatic, hydrological, and geological conditions, and the abundance of surface water resources, Alborz Province has not been spared this hazard. According to studies conducted by the Geological Survey and Mineral Exploration Organization of Iran since 2005, the plains of this province have been classified as critical. Examination of land subsidence evidence in Alborz plains indicates that the most significant impact of groundwater extraction has been observed in the Hashtgerd plain, primarily due to fine-grained sediments in the central and southern parts of the plain and agricultural land use. The geological conditions of the Karaj plain appear to control this phenomenon, minimizing its damages.
According to the results of remote sensing, only 8% of the area of ​​the Eshtehard plain is involved in subsidence at a rate of 3 cm per year. 92% of the plain does not have this risk. The subsidence center is in the west of Eshtehard plain with an area of ​​22.5 square kilometers. The maximum subsidence rate in the Eshtehard industrial town is estimated to be 8 cm per year as a point, which seems to have occurred due to the exploitation of deep wells and under the influence of the subsidence cone.
The Fissures Observed in the Eshtehard plain since 2005 have been Attributed to land subsidence. Due to the expansion of cracks in the area, urban infrastructures including power transmission towers and electric poles and buildings have been damaged. Over time, these collapses have been affected by water erosion, and the bottom layer, which is made of sand, has been emptied, resulting in the collapse of the roofs of the tunnels, and thus, with the development of these channels, a large area of ​​the plain has been involved in these cracks. .
However, fissures in the Eshtehard plain are attributed to fine-grained and dispersive soils that lack load-bearing capacity. Inappropriate land use, disruption of the region’s hydrological cycle, and the alternation of wet and dry conditions have caused these fissures to manifest as various cracks in the clay soils.
From a sedimentological perspective, the presence of a 3-4 meter layer of fine grain silt and clay deposits is evident in all areas involved in the gap. This clay layer is resistant to the passage of water and has no hydraulic conductivity. At a depth of more than 3 meters, there is a permeable layer of sand, which has created deep tunnels with the passage of subsurface flow and the washing of sand over time. Over time, these fissures, under the influence of water erosion, have evolved into large gullies. Analyzing the subsidence phenomenon in any plain requires a thorough understanding of aquifer geometry, geophysical studies, geology, and hydrogeology. Comprehensive studies and the tectonic conditions of the Eshtehard plain indicate the presence of two distinct sedimentary environments in the plain. In the eastern part of Eshtehard, a shallow surface aquifer exists, and due to low water quality and minimal exploitation, subsidence is not an issue. However, the western part of Eshtehard forms a deep sedimentary basin, containing fine-grained clay and silt interlayers up to a depth of approximately 70 meters. In this aquifer, excessive exploitation since 1986 has led to a 40-meter decline in groundwater levels. Near the Eshtehard industrial park, this change in water levels has reversed the hydraulic gradient and disrupted the balance of the groundwater table. Consequently, subsidence has occurred in the deep western aquifer, necessitating measures to control exploitation. However, surface fissures observed 7 kilometers west of the Eshtehard aquifer are not the result of horizontal ground movements due to subsidence. Soil mechanics studies confirm that these fissures are due to the soil and sedimentary characteristics of the region, exacerbated by climatic events and intensified over time by improper land use and loading.

Abstract Introduction:
Land subsidence, defined as the downward movement of sediments, is one of the significant geological hazards primarily caused by the decline in groundwater levels and the increase in effective stress in aquifer sediments. This phenomenon leads to considerable damage to surface and subsurface infrastructures, including road networks, urban water and sewage systems, and buildings. However, due to the relatively low immediate human casualties, it has not been considered a serious hazard. Over time, the continued subsidence of land results in irreparable damage to urban infrastructure. In most plains of the country, especially in densely populated provinces, excessive groundwater extraction has led to land subsidence.
Alborz Province is no exception and is considered one of the high-risk areas in the country. Studies on subsidence in Alborz Province began in 2005, conducted by the GSI. In 2017, the organization's Remote Sensing Group updated these studies to monitor subsidence and its development patterns in Alborz Province. Research Findings Using radar interferometry technology, the maximum rate of subsidence in Nazarabad Plain was calculated for the period 2014–2017, revealing a maximum rate of 22 centimeters.
Result:
In addition to the rates obtained from remote sensing studies of the GSI, data prepared by the land subsidence portal under the name COMIT-LICS were also used. The subsidence rates obtained from the processing of COMIT data are consistent with the studies conducted by the GSI. The 9-year subsidence rate for the Hashtgerd plain is more than 90 centimeters cumulatively.
Additionally, the groundwater level decline model for Hashtgerd Plain, developed using data from the Alborz Regional Water Management, along with geological and sedimentological analyses of the area, was used to assess the causes of subsidence in Nazarabad Plain. In the northern parts of the Hashtgerd Plain, due to the coarse-grained nature of the sediments, the aquifer receives adequate recharge, which helps reduce the subsidence rate. In the central parts of Hashtgerd Plain, limited recharge from the north and south, the fine-grained sediments, and the presence of clay interlayers result in the highest subsidence rates. In the northern parts of the Hashtgerd Plain, there is no evidence of land subsidence due to the significant accumulation of coarse-grained sediments from the Karaj and Kordan rivers. Although the greatest decline related to groundwater withdrawal occurs in this Part of the Plain. In fact, the result of high withdrawals from the groundwater table in the north of the plain has been manifested in the form of subsidence due to the drop in water level in the fine-grained sediments in the southern parts.
Discussion: 
Changes in Hashtgerd groundwater level over 25 years using the Surfer model software. The behavior of the level lines is an expression of the aquifer geometry. Therefore, to interpret and analyze the risk of subsidence, a set of different factors must be evaluated. The complexities of the Hashtgerd plain's groundwater table affect water resource management. The geology and hydrogeology of the plain are such that the spread of subsidence can be prevented by aquifer management and balancing. Currently, the central and southern parts of the Hashtgerd Plain are at risk of subsidence. The depletion of groundwater resources and excessive exploitation in the north, on the one hand, will limit the supply to the aquifer in the central parts of the plain, and on the other hand, will lead to the reversal of the hydraulic gradient and the ineffectiveness of controls and balancing.
Conclusion:
The total number of wells drilled in the Hashtgerd Plain aquifer is 2,852, with a withdrawal volume of 241 million cubic meters. The share of wells in the subsidence area is 518, of which 211 are abandoned according to the Ministry of Energy statistics. The volume of water that can be withdrawn in this area is 58 million cubic meters, which 24% of the total water withdrawn from the plain. The results of the study of groundwater level changes in the Hashtgerd Plain show that an area of the plain that is at risk of subsidence, based on field evidence, has fewer wells and fewer discharges compared to the entire plain.
The specific geological and geomorphological conditions of the Hashtgerd Plain and the presence of the permanent and abundant Kordan River have a positive effect on controlling the subsidence rate. Therefore, to control the subsidence rate, monitor and prevent future damage, it is recommended to: manage the aquifer and create underground dams to increase the water level in the north of the plain, control surface water and implement artificial recharge plans; identify the geometry of the aquifer, and identify the type of aquifer in the Hashtgerd Plain using pumping tests.

Abstract Introduction
Mass movements include all movements that occur under the influence of mass weight. The landslide occurred in the last days of 2018 and early 2019 after floods in many provinces of the country, including North Khorasan, Golestan, Semnan, Mazandaran, Gilan, Hamedan, Lorestan, Kurdistan, Kermanshah, East and West Azerbaijan, and Zanjan. Due to the large number of landslides in rural areas of the country, the perspective of moving to another location and escaping from landslides has changed and the approach of stabilizing the landslides that have occurred and building in situ has been replaced. Therefore, the stabilization and stabilization of a large number of landslides that occurred in late 2018 and early 2019, including the landslides in Hossein Abad Kalpoosh village in Miami County, Semnan Province, was placed on the agenda of the responsible executive agencies.
Materials and methods
Hossein Abad Kalpoosh village is located in Kalpoosh district of Miami city in Semnan province, at coordinates 37/2003445 and 55/736813. This village is located in Sudaghlan rural district (Razvan) and according to the census of the Statistical Center of Iran in 2016, its number of households was 1013 and its population was 3514. Upstream of this village, a Kalpoosh reservoir dam has been constructed close to the village, which has been impounded in recent years. The research method in this study is based on library surveys and studies and field observations. In this regard, information related to the geological, tectonic and landslide conditions that have occurred in the village area is examined in a library manner, and then the method of landslide management and stabilization is examined. After completing the geological information, faults, landslides that have occurred, and their location, the data will be analyzed and the methods and technical measures taken to stabilize and stabilize landslides will be examined in order to prevent the displacement of the village and the migration of villagers, and to continue the settlement of villagers in the current location of the village, and to determine the direction of village development and their efficiency.
Results and discussion
A large number of landslides also occurred in the village of Hossein Abad Kalpoosh in Miami County, Semnan Province. The landslides that occurred in the village were categorized into 5 different zones, including 1- the landslide zone downstream of Kalpoosh Dam, 2- the landslide zone above the neighborhood and the southern slopes of the Ghoshe-Dagarman River, 3- the landslide zone above the Saadat Abad neighborhood, 4- the Besat Abad landslide zone, and 5- the landslide zone of Hassan Abad neighborhood and its upstream slopes. The largest landslide area is located downstream of the Kalposh Dam, which has destroyed many homes. This landslide, with an area of about one and a half hectares and an average depth of 11 square meters, occurred in the heart of a large old landslide area. This landslide, with an area of about one and a half hectares and an average depth of 11 square meters, occurred in the heart of a large old landslide zone. It seems that this old landslide in the downstream section of Kalpoosh Dam had a great depth of more than 30 meters and occurred at the border of wind-blown and weak marl deposits with strong underlying limestone bedrock, and in some places it also contains fragments of the underlying bedrock. The recent landslide occurred on March 11, 2018, with a combined rotational-transitional movement, after heavy snowfall in February and heavy rainfall in March. Although the existence of an old landslide and the heavy rainfall mentioned above played an important role in the occurrence of this landslide, the available evidence indicates that the more effective role was played by the rising water level in the Kalpoosh Dam reservoir, the seepage of water through the crushed rocks of the reservoir wall, and the saturation of the soil mass from the lower part. This is evidenced by the occurrence of numerous springs and seepages in this range, which continued for many months after the landslide occurred, and only with the lowering of the water level in the reservoir, these seepages have begun to decrease. The recent landslide occurred on March 11, 2018, with a combined rotational-transitional movement, after heavy snowfall in February and heavy rainfall in March. Although the existence of an old landslide and the heavy rainfall mentioned above played an important role in the occurrence of this landslide, the available evidence indicates that the more effective role was played by the rising water level in the Kalpoosh Dam reservoir, the seepage of water through the crushed rocks of the reservoir wall, and the saturation of the soil mass from the lower part.
This is evidenced by the occurrence of numerous springs and seeps in this range, which continued for many months after the landslide occurred, and only decreased as the water level in the reservoir decreased. The landslides damaged a large number of rural homes, facilities and infrastructure. In order to stabilize and stabilize the landslides that occurred in the village, 8 machine boreholes and 6 geoelectric profiles with a dipole-dipole array, three S and P wave boundary rupture seismic profiles, single station and microseismic array surveys (microtremor) including one in-situ array survey and 17 single station surveys have been conducted. Subsequently, stability analyses and landslide stabilization options were conducted, and finally, plans and implementation plans were presented to stabilize the village's landslides and make rural homes safe, and the aforementioned plans have been implemented.
Conclusion
By stabilizing, stabilizing, and securing the village of Hossein Abad Kalpoosh, the migration and relocation of approximately 1,000 households with a population of over 3,500 people was prevented, and the harmful consequences of unsuccessful relocations were prevented. According to available information, 881 villages have been displaced across the country by 2015, most of which were displaced due to risks arising from various natural disasters, with the most important risks causing displacement including floods, earthquakes, and landslides, so that more than 74 percent of displacements in the country are due to the above factors (Gerkani et al., 2018). Sabouri and Garkani (1403) conducted a field study of 9 new sites of relocated villages, all of which were unsuccessful in their relocation and the village was not formed in the new site. Therefore, by adopting recommendations and conducting studies and implementing sustainability plans in the village of Hossein Abad Kalpoosh, the repetition of unsuccessful and costly experiences of rural relocation has been prevented.

Abstract Chalus Road, as one of the main axes of communication between the north and south of Central Alborz, has always witnessed the occurrence of numerous rockfalls and this causes countless damages. In this article, the method of dispersion and the reasons for the occurrence of these spills are investigated. For this purpose, the method of risk zoning of rock fall using rock engineering factors has been used. The results show that between the Karaj Dam and the beginning of the urban area, there are at least nine main areas where rock falls affect the road axis. Asara shales, middle tuff member, and Quaternary units respectively have the highest amount of rockfall origin. Except for some areas, there is no defined connection between the tectonic fracture zones and the starting points of rockfalls. Statistical studies show that most landslides occur at the end of winter and the beginning of spring. Regardless of the fact that tectonics has caused the fragmentation of the rock units of the region, the time of occurrence of the events shows their direct relationship with the Quaternary climate. It is suggested that the road department implement stability systems and rockfall control in identified high-risk areas in order to prevent future disasters

Chalus Road, as one of the main axes of communication between the north and south of Central Alborz, has always witnessed the occurrence of numerous rockfalls and this causes countless damages. In this article, the method of dispersion and the reasons for the occurrence of these spills are investigated. For this purpose, the method of risk zoning of rock fall using rock engineering factors has been used. The results show that between the Karaj Dam and the beginning of the urban area, there are at least nine main areas where rock falls affect the road axis. Asara shales, middle tuff member, and Quaternary units respectively have the highest amount of rockfall origin. Except for some areas, there is no defined connection between the tectonic fracture zones and the starting points of rockfalls. Statistical studies show that most landslides occur at the end of winter and the beginning of spring. Regardless of the fact that tectonics has caused the fragmentation of the rock units of the region, the time of occurrence of the events shows their direct relationship with the Quaternary climate. It is suggested that the road department implement stability systems and rockfall control in identified high-risk areas in order to prevent future disasters

Chalus Road, as one of the main axes of communication between the north and south of Central Alborz, has always witnessed the occurrence of numerous rockfalls and this causes countless damages. In this article, the method of dispersion and the reasons for the occurrence of these spills are investigated. For this purpose, the method of risk zoning of rock fall using rock engineering factors has been used. The results show that between the Karaj Dam and the beginning of the urban area, there are at least nine main areas where rock falls affect the road axis. Asara shales, middle tuff member, and Quaternary units respectively have the highest amount of rockfall origin. Except for some areas, there is no defined connection between the tectonic fracture zones and the starting points of rockfalls. Statistical studies show that most landslides occur at the end of winter and the beginning of spring. Regardless of the fact that tectonics has caused the fragmentation of the rock units of the region, the time of occurrence of the events shows their direct relationship with the Quaternary climate. It is suggested that the road department implement stability systems and rockfall control in identified high-risk areas in order to prevent future disasters

Chalus Road, as one of the main axes of communication between the north and south of Central Alborz, has always witnessed the occurrence of numerous rockfalls and this causes countless damages. In this article, the method of dispersion and the reasons for the occurrence of these spills are investigated. For this purpose, the method of risk zoning of rock fall using rock engineering factors has been used. The results show that between the Karaj Dam and the beginning of the urban area, there are at least nine main areas where rock falls affect the road axis. Asara shales, middle tuff member, and Quaternary units respectively have the highest amount of rockfall origin. Except for some areas, there is no defined connection between the tectonic fracture zones and the starting points of rockfalls. Statistical studies show that most landslides occur at the end of winter and the beginning of spring. Regardless of the fact that tectonics has caused the fragmentation of the rock units of the region, the time of occurrence of the events shows their direct relationship with the Quaternary climate. It is suggested that the road department implement stability systems and rockfall control in identified high-risk areas in order to prevent future disasters

Abstract 1-Introduction
Mass movements include all movements that occur under the influence of mass weight. The effect of fault zones and tectonic activity on landslides and the relationship between them can be evaluated by examining the density of landslides in the fault zone and their boundaries and the impact of tectonic activity on landslides. The impact of tectonic activity by the occurrence of an earthquake and the creation of a driving force, tectonic uplifts, the creation of conditions and materials prone to landslides through the creation and development of fractures and cracks caused by faulting, the creation of cracks and fissures in rocks and acceleration The process of mechanical and chemical weathering, creating gouges and cutting faults; Increasing the permeability of rocks is a change in the amount and direction of the slope of the geological and topographical layers.
2-Materials and methods
The study scope includes the entire country. The location of all the landslides detected in Iran and the known faults of Iran, the slope of the landslides and field observations and technical investigations of three cases of landslides near the faults have been investigated. The research method in the present study is based on library studies and field observations. In this regard, the information related to the state of geology, tectonics and landslides that occurred in Iran is examined in a library form, and then the information of previous landslides has been collected and compared to Field investigation of old and new landslides is discussed. After completing the geological information, faults, landslides and their location, he analyzed the data and analyzed and compared the location of landslides with faults using Arc Gis software. And the slope of their place of occurrence is done. Also, as an example, several cases of landslides that have occurred in the area of ​​active faults have also been investigated and the effect of the fault zone on the occurrence of landslides will be analyzed. Finally, by analyzing the results of comparing the occurrence of landslides with the location of the faults, the evaluation of the active tectonics is carried out.
3-Results and discussion
The relationship between tectonic activities and the occurrence of landslides has been investigated by different researchers and confirmed in different regions. Therefore, considering that tectonic activity is caused by the occurrence of earthquakes and the creation of a driving force, tectonic uplifts, fractures and crushings caused by faulting, the creation of cracks and fissures in rocks and the acceleration of the process of mechanical and chemical weathering, the creation of fault gouges and cutting A fault as a material prone to landslides, increasing the permeability of rocks, changes in the direction and slope of geological layers, etc., cause landslides, the relationship between tectonic activity and landslides was investigated. Therefore, by comparing the location of the landslides detected in the country with the active faults of the country, it was found that the density of landslides is higher in the area near the active faults. As it was determined in the observations and field investigations of three selected landslide samples in Zagros, Azerbaijan and Alborz region (including the landslides of Qala Rostam, Kafcherin and Qafe Bala Qala), the activity of faults causes fractures, crushing, increased permeability, Changes in the slope and layering of rocks, and most importantly, have caused landslide-prone materials. However, it was not possible to convert this impact into quantitative data due to geological conditions and lack of data, and it was enough to interpret and describe this impact qualitatively. Also, by examining the location of the landslides that occurred in the country and the slope of the landslides, it was found that a high percentage of landslides occurred at slopes higher than 15 degrees, and qualitatively, it can be related to the slope and elevation of the mountain. established with tectonic activity and described the effect of tectonic activity on the occurrence of landslides.
4- Conclusion
By comparing the location of landslides detected in the country with active faults in the country, it was found that the density of landslides is higher in the vicinity of active faults. So that in the range of 500 meters and 2000 meters of active faults, the number of detected landslides is 65% more than the areas far from the fault, and a high percentage of landslides occurred at slopes higher than 15 degrees, which is due to It is influenced by tectonic activity due to the increase in the slope and elevation of the mountains. According to the field investigation of three landslide samples, the effect of fault activity on the creation of landslide-prone materials was determined. Therefore, one of the main factors of the occurrence of landslides and the frequency of their occurrence in the fault areas and close to the faults can be considered as the effect of tectonic activity and faults, which through the occurrence of earthquakes and the creation of a driving force, tectonic uplifts, fractures and crushing caused by faulting, creation of joints and cracks in rocks and accelerating the process of mechanical and chemical weathering, creation of fault gouges and fault cuts as materials prone to sliding, increasing the permeability of rocks, changes in the direction and degree of slope of geological layers, etc. In other words, it can be said that tectonic activities have increased the occurrence of landslides in the country. In terms of the vulnerability of residential areas and other important facilities located near active and quaternary faults, in addition to seismic waves and surface rupture during an earthquake, they are also threatened by the risk of landslides. Therefore, it is necessary and necessary to adopt engineering measures in the construction of houses located in fault zones to prevent damage caused by landslides, as well as not to build on sloping land and away from the boundaries of fault ruptures.

Abstract Introduction: Damghan area has been considered by earth scientists due to the existence of numerous active faults. These faults with slow and progressive movements have led to changes in the shape of landforms in the area. Even during the history, the activity of these faults led to major earthquakes such as Qumis earthquake in 856 A.D. This earthquake led to the complete destruction of Qumis province in present-day Damghan. Researchers in the area, including Hollingsworth et al 2010., have concluded that major faults in the area, such as the Astaneh and North Damghan faults, have ruptured during the Qumis earthquake. The changes in landforms and high potential of faults in creating seismic events indicate their continuous activity during Quaternary up to now.  To study these changes, we need those features that are sensitive to tectonic and erosive events. Rivers are one of these features that react quickly to active tectonic and erosion changes. The main purpose of this study is investigation of the changes in landforms using anomalies in stream orders. Because there is a hypothesis that claims tectonic and erosive changes lead to irregularity in Strahler orders of streams. In this study we use isobase and differential map method to investigate this hypothesis.
Materials and Methods: Sensitivity of drainage network to tectonic processes and geological contradictions leads to changes and irregularities in river orders. Isobase maps are extracted from information about the spatial classification of rivers and their elevation information in the environment. In fact, these maps show the relationship between the pattern of waterways and the topography of landscapes. Streams with the same Strahler order are formed by the same geological events, and most likely the same order is the same age. We can draw iso base maps for different stream orders. Early orders (1-3) are mostly more sensitive to tectonic events. These early orders due to flow along seams and fault gaps are representative of neotectonic. Rugged structures in the lithology of the region can limit the evolution and development of the early orders, and therefore in these areas the values of the isobase map increase. But isobase map of evolved orders can represent longer periods, such as the Quaternary or Pleistocene. Because evolved orders are formed over longer periods and are able to show older tectonic and erosive events. Differential maps are obtained from the difference in height between the maps of the evolved orders and the present day topography map.
Results and Discussion: Examination of the isobase map of the primary orders show that most of the values related to the map can be seen in the west and north of the region. These areas are based on mountainous structures. The high values of the isobase map in these areas indicate that the northern and western parts, affected by neotectonic activities and the development of fault gap and seams, have more primary orders of rivers. Because most of these primary orders are formed and developed along these levels of weakness. Resistant lithology of the area has also prevented the development of these orders. The highest value of them is 3830-2312 meters. The differential map prepared from the study area shows a wide range of positive values indicating uplift and negative values indicating subsidence. By examining these values, we can understand the features related to tectonics and geomorphology of various landforms in the region. The highest values of 1191 to 800 meters are related to the high mountain structures of Eastern Alborz in the north and west of the region. The decrease in the value of the differential map indicates the effect of tectonic subsidence on the morphological landforms of the region. The Astaneh pull apart basin in the western part of the region shows the amount of subsidence between -4 to -1 meters. Also, the southern playa of Damghan in the form of a concave foreland basin affected by active faults in the region shows negative values, which indicates the existence of a submerged basin with high sedimentation potential.
Conclusion: Studies conducted on the area show that the two factors including active tectonic and lithology have a great impact on the morphological structures and landforms of the area. The results of isobase map and the differential map show and confirm this issue. The methods used in this study to investigate the tectonic activity of the faults in the area indicate their activity during the Quaternary. These faults have different mechanisms of thrust and streak slip which in some areas also have transtensional and transpressional position; they have created a collection of uplifted or concave landforms in Damghan area. The spatial relationship between different values from north to south in the prepared maps indicates the creation of an equivalent states between topographic growth and its destruction in lower altitudes. Based on the studies, we confirm that the preparation of isobase and differential maps can be a suitable method for studying and examining morphological structures. Also studies related to differential map show anomalies in drainage networks and uplift processes associated with active Quaternary landforms can be quantified by these maps.  Using baseline and differential maps is one of the appropriate methods to study the Plio-Quaternary tectonics in an area. This study confirms the work of previous researchers based on the available information and documents related to the study area.
 

Abstract Quaternary volcanic activity, as the last magmatic effort in Iran, is the evolution of large volcanic cones such as Damavand, Sahand, Sablan, Taftan and Bazman, as well as lava flows such as Mako basalts and Lot block. Sablan, a young member of the Cenozoic volcanic complex, belongs to the Alborz magmatic arc (AMA). In Sablan Mountain, there is a collection of volcanic rocks with the composition of andesite, basaltic andesite, dacite, rhyodacite and trachy andesite. The texture of these rocks is mostly porphyritic with microlithic clay, porous porphyritic, sometimes glomeroporphyric, sieve and trachytic. Among the main minerals, plagioclase and one or more mafic minerals such as hornblende and pyroxene can be mentioned. Secondary minerals include opaque minerals, edengsite, chlorite and calcite. In the normalized multi-element diagrams, relative enrichment of K, Ba, Rb and relative depletion of Ti, Ta, and Nb indicate magmatism affected by subduction processes. In terms of the chemical composition of these rocks, the main elements such as K₂O, Na₂O, MgO, Al₂O₃, SiO₂ Mg# and K₂O/Na₂O and the composition of rare elements such as Cr, Ni, Yb, Y, Sr, Rb Sr/Y and La/Yb are in the range Adakite stones are placed. In addition, the geochemistry of these rocks, including the concentration of Cr, MgO, Th, Rb, Th/Ce, and K₂O/Na₂O, is in better agreement with the adakites derived from partial melting of the subducted oceanic sheet. According to the petrographic diagrams, the adakitic magma forming these rocks was formed from the partial melting of an eclogitic source rock or amphibolite garnet resulting from the metamorphism of the subducted Neotethys oceanic plate under Central Iran. Keywords: petrology, PULL PARAT, petrogenesis, Iran.

Abstract Introduction
Rivers are one of the most important water resources and it is very important to study their water quality. Therefore, in this study, sampling was done from 15 permanent waterway stations of Pirbadush and Gashun of Qolyan River in Lorestan province, which are located in the path of oil shales.
 
Materials and Methods
 Hydro-geochemical parameters were calculated by analyzing the samples in the laboratory. Then compared with drinking water quality assessment standards in the region and Hydro-geochemical diagrams were also drawn.
Discussion and Results: Qolyan River water contains a lot of calcium carbonate and only sample P3 has more magnesium carbonate that it is unsuitable for drinking due to its high calcium content, but it is suitable based on other parameters.
 
Results
According to Schoeller quality classification, Gashun samples are of lower quality than Pirbadush and by the standards, most samples are within the allowable-favorable range and water of G6, G7, P5 stations have lower quality than other stations. According to the WHO table, the water of the Qolyan River is relatively light in terms of TH and total dissolved solids (TDS) and relatively light in terms of Electrical conductivity (Ec). Based on hydro-chemical tests and data analysis and hardness estimation and comparison with the national standard of Iran and the standard of the World Health Organization, the results of water classification of the samples are as follows: According to the World Health Organization's calcium ion (Ca^{2 +}) content, water samples from G7 and P5 stations are impermissible and based on the total hardness of the Iranian national standard, the water samples of stations P1 and P3 are in the favorable level.
According to hydro-geochemical diagrams, the water quality of Pirbadush waterway is better than Gashun. According to the Piper diagram, In Gashun samples, the tendency of the samples towards magnesium and sulfatation is more than the samples of Pirbadush region. According to the Durov diagram, most of the water samples taken from Gashun and Pirbadush waterways are calcium carbonate (Ca-CO₃) and calcium bicarbonate (Ca-HCO₃). According to Schoeller diagram, the amount of tumble in the samples of Gashun waterway is more than Pirbadush waterway. According to the ion equilibrium diagram, the amplitude of change of anions and cations in Gashun waterway is more than Pirbadush. According to Stiff diagram, the different origins of the samples indicate the existence of several bedrock sources for the samples, and according to the Gibbs diagram, bedrock and weathering and dissolution are the main factors controlling the water chemistry of the region.
By examining the water quality of Qolyan River in Pirbadush and Gashun waterways with any human activity that it is in the path of oil shales, the results were obtained which are:
-The highest amount of cations and carbonate anion (CO₃^2-), is in G7 station and the highest amount of nitrate anion (NO₃^-), are in G6 and P7 stations.
-The highest water total hardness (TH) is related to stations G7, G6, P5 and the lowest is related to stations P3, P1, G1.
-The highest total dissolved solids (TDS) in water is related to stations G6, G5,  G7 and the lowest amount is related to P1, P4, P3.
- The presence of higher amount of calcium carbonate (Ca-HCO₃) in Gashun waterway than Pirbadush indicates a higher degree of solubility of calc than dolomite in this section.
- High sulfate content in Gashun waterway (especially G1 station) can be related with further dissolution of anhydrites in the Gotnia Formation.
-Anion and cation equilibrium also shows that ionic equilibrium is present only at stations G3, G5, P6. However, at stations P1 and P3, there is a high degree of ionic imbalance between anions and cations.
 
Conclusion
 In this area, the type of rock units and even the presence of oil shales have not had a detrimental effect on the quality of drinking water.

Abstract Abstract
The population growth, the development of cities, industry, agriculture, and improper use of resources especially non-renewable resources have led human beings to face the danger of running out of resources. In some cases, in addition to the above, irreversible environmental and geological hazards have occurred due to the overdrawn of resources. Over extraction of groundwater resources is one of the problems that, in addition to human exposure to the risk of water scarcity, also induces risks due to this over-harvesting. The phenomenon of land-subsidence is called subsidence for natural and human reasons. One of the reasons for this phenomenon is human activities, including the overextraction of groundwater resources and the water table drop. Subsidence itself results in some problems such as deep cracks in the ground, well pipes growth and collapse of buildings. One of the common subsidence damages in many plains of Iran is the creation of sinkholes. Sinkholes are deep pits that are mainly involved in the development of karst dissolution and subsequently many risks to urban and environmental areas. The areas affected by the subsidence phenomenon have been identified using the Synthetic Aperture Radar Interferometry (InSAR) method. The interferometry technique uses electromagnetic wave interference to extract information. Radar interferometry uses the phase difference of radar images with a high spatial resolution seeking to produce a digital elevation model of the region and estimate the amount of deformation and displacement of the earth's crust. In the radar interferometry technique, complex radar images containing the phase values ​​and amplitude of the wave returning from the complication to the sensor are combined and an image called an interferogram is produced. An interferogram is an image that results from the subtraction of two images taken at two different times that are aligned on each other. An interferogram contains information of the phase difference between the two images, which indicates the difference in distance between the terrain features and the sensor in the two captured images. By having the phase difference value, various parameters such as the amount of ground displacement can be obtained. Persistent Scatterer Interferometry (PSI) time series analysis method uses stable scattering pixels (pixels that have scattering patterns with a constant scattering pattern over time) to extract information and overcome the limitations of radar interferometry. In the present research, an attempt has been made to monitor the subsidence of Abarkooh using the Synthetic Aperture Radar Interferometry method.
Abarkooh region is located in Yazd province which is an agricultural region in recent decades and the extraction of groundwater resources has been increased in it. Abarkooh city has two urban points, Abarkooh and Mehrdasht. Excess extraction of groundwater caused numerous subsidence and sinkholes, subsequently. Hydrological studies have determined the rate of groundwater level drop equal to 0.6 m/yr. In this paper, by using 55 Sentinel-1A satellite images in the period of 2017 to 2019, 54 interferograms have been used to process time series analysis based on persistent scatterer after deducting the participatory phases from the interferogram phase.




* h.ansari@yazd.ac.ir




Finally, the average subsidence rate map for the Abarkooh region is estimated. According to the analysis, the maximum subsidence rate of the Abarkooh region is 3 to 4 cm /yr and the maximum subsidence rate of the Mehrdasht region is 6 to 7 cm/yr. Accordingly, by considering the location of the subsidence area in the agricultural lands of the studied region and the decrease of the water table level in that region, one may conclude that the subsidence has happened due to the over-extraction of groundwater resources. In order to investigate the impact of subsidence on the environment, the soil salinity map has been calculated. In general, the salinity of the region is increasing as a factor impacting the degradation of surface soils and desertification. Well pipes growth, sanding of water wells, and reduction of well’s discharge, all are some examples of the consequences of subsidence in the destruction of wells. Other consequences of subsidence in this area include turning the plain into a desert, damaging aquifers, changing the topography of the land, and environmental pollution. Due to the un-uniform distribution of the subsidence areas in ​​the region, the damages to roads, railways, urban and industrial buildings, and energy transmission lines have been predicted. One of the most important subsidence consequences in this area is the creation of deep holes and longitudinal cracks along with the subsidence area. To evaluate the results of the interferometry technique, GNSS station data have been used. Since the data related to this area are available from 2011 until now, it is possible to obtain an accurate evaluation of the InSAR results. The results show that the displacement rate is 1 cm based on the permanent station data (GNSS) and the interferometry measurement results show a displacement rate of 0.7 cm. These values indicate the accuracy of the results of radar interferometry.

Abstract Introduction

It produced millions of tons of solid waste annually during Iran's household, mineral, agricultural, and industrial activities that are heavy metal-rich. Solid waste generation is the most important environmental and health problem in the world, especially in developing societies. The rapid growth of urban, agricultural, and industrial activities, along with population growth, produces a wealth of waste. Open landfills are the oldest and most abundant solid waste landfill in the world. Uncontrolled landfills can have an adverse effect on the environment and human health. The most important risk of landfill on human health is sediment contamination by waste leachate. Municipal waste landfills can be associated with the release of contaminants due to leachate infiltration into sediments and surface and groundwater of the surrounding environment. The purpose of the present study was to determine the heavy metals contaminants of Arak landfill in comparison with the upper crust reference, to evaluate landfill pollutant indices at different depths, to determine the sources of Arak landfill and to determine the role of Arak landfill in the production of all types of heavy metals.
 

Materials and methods

Arak landfill is located in Amanabad plain and upstream of 14 drinking water wells in the Arak city. Annually, 350 tons of Arak's garbage is brought to the landfill, 30% of which is dry waste (paper, glass, metals) and the rest more waste (kitchen waste, food, fruits).Thirty one sediment samples were collected from three boreholes in Arak landfill in 1396 (borehole with 22.5 m depth, 13 samples, borehole with 17.5 m depth, 10 samples and borehole with 13 m depth, 8 samples). It was determined texture, physical and chemical composition and heavy metals(Pb, Cr, Ni, Cu, Zn, As and Hg) of the sediments.
 

Results and discussion

The mean concentrations of Pb, Ni, Cu, Zn, As and Hg were 32, 64, 25, 73, 15 and 6.90 mg / kg in Arak landfill sediments, respectively, and greater from their mean concentrations in the upper crust (17, 18,13, 47, 5 and 0.05 mg / kg). The average concentration of Cr (39 mg / kg) is lower than the mean concentration in the crust (92 mg / kg). The enrichment coefficients of Pb, Cr, Ni, Cu and Zn vary from low to medium, for As from low to very high, and extremely high for Hg. The geo-accumulation coefficient is low for all elements except for Hg. The geo-accumulation coefficient is medium for Hg.
Evaluation of the concentrations of Pb, Cr,Ni, Cu, Zn, As in three boreholes showed that their concentration did not show a specific trend towards depth. The enrichment coefficient and geo-accumulation coefficient for Pb, Cr,Ni, Cu, Zn, As were also absent trend. There is a great concentration of elements in specific  zones in depths. The amount of Hg as well as the enrichment coefficient and its geo-accumulation coefficient increase with increasing depth. In general, the degree of contamination of all elements increases with the depth in boreholes.
In factor analysis, Cu, Mn, Ni, Zn and Pb were positively correlated in one group. As, Hg and organic matter are in another group. The correlation of As with Hg and organic matter is reversed. Also, the variables of mud, sand and gravel were in the other group, in which gravels were inversely correlated with mud and sand. The study showed that heavy metal concentrations of Cu, Ni, Zn and Pb occurred in an environment with high Mn. It was also enriched Hg in organic matter environments. In contrast, arsenic enrichment is in a separate phase that has no relation to organic matter. In addition, it was found that sediment texture (mud, sand and gravel) did not play a role in the concentration of heavy metals in surface and deep sediment of Arak landfill.

Conclusion

The analysis of dry and wet waste in long-term landfill accumulation in direct contact with precipitation and the runoff has involved the decomposition of heavy metals into deep sediment. Organic matter and manganese compounds play the most important role in the distribution of heavy metals at different depths in the sediments. Therefore, monitoring heavy metals in landfill leachate and downstream drinking water wells is essential. Since landfill is old and not engineering landfills, therefore, new landfills must be designed on the principles of landfill engineering. In addition, hydrological removal can prevent water from being exposed to landfill

Abstract Abstract
In this research, Geophysical methods Ground Penetration Radar (GPR) and Geoelectric have been used to detect hidden Quaternary faults in alluvial sediments located southwest of Chitgar Forest Park (District 22 of Tehran). The study of profiles (GPR) identified areas such as fault. The results obtained from two Geoelectric profiles indicate that there are two zones with low electrical resistance and high electrical resistance. Reduce the electrical resistance in the sediments of the area can be related to factors such as the existence of non-weathered rocks, the air inside the sediments, fine-grained sediments and being a forest of the study area, due to irrigation of trees and rainwater penetration underground. High electrical resistivity indicates crushing of rocks by fault activity, coarse-grained and dry sediment. The results of the methods used in this research indicates that there is a fault zone with an approximate length of 140 m. Considering the structural trends of most of the faults identified, it is very likely that the faults will continue along the upper part of the Chitgar Park. Due to the seismic potential and vulnerability of residential structures, especially in the north and northwest of the study area, the results of this research are important. Its use is recommended for analyzing tectonic hazards and improving the quality of thematic maps.



Evaluation of Geophysical methods for identifying hidden Quaternary faults in alluvial sediments (case study: Chitgar Park)


Abbas Aliyannezhadi, Seyyed Reza Mehrnia ^*, Salimeh Kimiagar, Habib Rahimi, Nasrin Sadrmohammadi


Associate Professor of Geology


 


Abstract:   (3456 Views)


Abstract
In this research, Geophysical methods Ground Penetration Radar (GPR) and Geoelectric have been used to detect hidden Quaternary faults in alluvial sediments located southwest of Chitgar Forest Park (District 22 of Tehran). The study of profiles (GPR) identified areas such as fault. The results obtained from two Geoelectric profiles indicate that there are two zones with low electrical resistance and high electrical resistance. Reduce the electrical resistance in the sediments of the area can be related to factors such as the existence of non-weathered rocks, the air inside the sediments, fine-grained sediments and being a forest of the study area, due to irrigation of trees and rainwater penetration underground. High electrical resistivity indicates crushing of rocks by fault activity, coarse-grained and dry sediment. The results of the methods used in this research indicates that there is a fault zone with an approximate length of 140 m. Considering the structural trends of most of the faults identified, it is very likely that the faults will continue along the upper part of the Chitgar Park. Due to the seismic potential and vulnerability of residential structures, especially in the north and northwest of the study area, the results of this research are important. Its use is recommended for analyzing tectonic hazards and improving the quality of thematic maps.
Keywords: Electrical resistivity, Fault zone, Ground Penetrating Radar, Landform, tectonic hazards.
 

*Corresponding author: Email: r_mehrniya@pnu.ac.ir, Phone: +98 9122574607 Fax: +98 21 22440925 Address: Payame Noor university of Tehran, Artesh boulevard, Emam Ali freeway, Tehran, Iran.
 
 
Introduction
In spite of intense erosion, extensive vegetation, human activities and presence of higher thickness of sediments which make it difficult to access Quaternary earthquakes documentation, over the past two million years, we have been witnessed tectonic movements and the vast majority of changes in landforms which most of them are important in Seismological engineering.
There are large and small faults in the mega-city of Tehran, which mainly have sheared off and moved the Tertiary-Quaternary sedimentary sequences. One of the main faults in Tehran is "North Tehran fault", which is the most dangerous and most controversial seismic fault with East to West direction. This fault located in the north of Tehran between the mountains and the piedmont of Central Alborz.
The study area is located in 22nd District of Tehran Municipality (in the southwestern of Chitgar Forest Park) with UTM coordinate (Easting: 517658.75/ Northing: 3955301.99). This area is located in the B-series alluvial sediments of Tehran plain. Geologically, it includes unconsolidated sediments such as boulder, cobble, gravel and sand which were deposited and transported from the southern slopes of the Alborz Mountains. Based on of Tehran geological map (1.100.000), the geologic units Qt2 (Low level piedment fan and valley terrace deposits) and Qplc (Fluvial conglomerate, Piedmont conglomerate and sandstone) are recognized. In addition, part of the sediments recognized, layers of old soil and pseudo-Laterite are seen. These layers indicate climate changes and the effect of warmer weather.
Due to the factors such as being covered some of the faults with Quaternary alluvial Sediments, Extensive urban development of the city of Tehran (especially 22nd district) and outcrop of subsidiary faults in alluvial Sediments of Azadshahr fault (most important factor), Geophysical methods usage such as GPR (Ground Penetrating Radar) and Electrical Resistivity are considered.
Method and Material
In this research, the GPR data was acquired by the MALA RTA-50 (Rough Terrain Antenna) System with an antenna of 50 MHz. The maximum penetration of RTA-50 is about 30 meters. The profile is adjusted with the time record system. Two geoelectric profiles were taken along the trench. For processing GPR data and geoelectric profiles from Reflex W and RES2DINV software were used.
Discussion
According to the GPR profile, faults, fractures and displacement of the layers were identified. Generally, a fault zone is observed a distance of 110 to 380 meters. Pole-Dipole array method was used to investigate the geoelectrical resistivity of the studied area.  The Data acquisition includes two 160 meters profiles with a distance of 60 meters from each other. The results obtained from two Geoelectric profiles indicate that there are two zones with low electrical resistance (28-38 ohms) and high electrical resistance (137-233 ohms) in the first profile (At a distance of 75-85 meters) and low resistance (15.2-23.6 ohms) and high resistance (208-328 ohms) in the second profile (At a distance of 80-90 meters) they exist. Reduce the electrical resistance in the sediments of the area can be related to factors such as the existence of non-weathered rocks, the air inside the sediments, fine-grained sediments and being a forest of the study area, due to irrigation of trees and rainwater penetration underground. High electrical resistivity indicates crushing of rocks by fault activity, coarse-grained and dry sediment.
Conclusion
The results of the methods used in this research indicates that there is a fault zone with an approximate length of 140 m. Also, the data processed for GPR profile indicative the effects of the faults and changes in the stratification of layers at distance mentioned and proves the results of the electrical resistivity method. Changes and function of active faults but hidden in the study area can be closely related to the location of this area adjacent to the main North Tehran fault and the effects of this great fault. Considering the structural trends of most of the faults identified, it is very likely that the faults will continue along the upper part of the Chitgar Park. Due to the seismic potential and vulnerability of residential structures, especially in the north and northwest of the study area, the results of this research are important. Its use is recommended for analyzing tectonic hazards and improving the quality of thematic maps.