Quaternary Journal of Iran

Abstract Introduction
As one of the most seismic regions in the world, Iran has two main tectonic belts (Berberian and King, 1981). The Zagros belt, which starts from the eastern end of the Makran subduction zone in the Oman Sea. The trend of this belt is southeast-northwest and its other side is limited to the eastern corner of the North Anatolian fault (Nissen et al., 2019). The Alborz tectonic belt starts from this point with an east-west trend and extends to the Kepe Dagh fault in the northeast corner of Iran (Alavi, 1996). The central part of the Alborz belt is surrounded by active faults that have caused the destruction of cities in the region in the past centuries (Zanchi et al., 2007). Investigating the activity of these faults and how they function during a major earthquake event is very important (Berberian and Yeats, 2016). On the other hand, the effect of the construction in the dispersion of the waves of such earthquakes can significantly affect the destruction of the structures (Habibi et al., 2023). On average, from 1900 to 2014, 3 people died every hour in Iran due to earthquakes (Berberian, 2014). Such a shocking statistic makes it even clearer that it is necessary to pay more attention to the conditions of the building.

Materials and Methods
Systematic records of earthquakes that occurred in Karaj and its surrounding areas have been prepared from the catalog of various international sources and published studies. Sources of earthquake records include the International Seismological Center (ISC) comprehensive catalog from 1908 to 2023, the Global Earthquake Model (GEM) catalog from 1903 to 2019, and historical earthquake records from published studies (Ambraseys and Melville, 1982; Berberian, 1995; Berberian et al. ., 1983, 1985) was collected for an area with a radius of 150 km from Karaj. It was tried to add the relevant earthquakes to the catalog in cases where the length of active faults in the region is outside this radius. Seismic records are collected, reformatted, and stored chronologically to produce a uniform composite seismic catalog.
The catalog of clustered earthquakes for the period 1762 to 2023 is not complete. Seismic rates predicted using the earthquake events in this list may underestimate the occurrence of future earthquakes in these regions. A reliable mean seismic rate can be predicted by identifying the period over which the catalog is complete for a given magnitude range. Therefore, completeness periods for different magnitude ranges are determined using the Step method (Stepp, 1972).
Results and Discussion
In addition, during the return periods of 475 and 975 years, the values of earthquake acceleration from the PGA period have an increasing trend until 0.2 seconds and then decrease. But in the return period of 2475 years, the upward trend is observed even up to a period of 0.3 seconds.
In order to control and check this point, it is necessary to use earthquake risk separation charts. The relative contribution of seismic sources (isolation model) in seismic hazard (PGA) and period of 0.3 s for three return periods of 475,974,2475 years for the central point of Karaj city are shown in Figures 6 and 7. Also, the numerical values obtained from these graphs are presented in Table 4. The percentage values of the contribution of each of the seismic sources in the total risk are displayed as a pie chart. In all the analyzes of Table 4, the share of faults in the total risk is North of Karaj, North of Tehran, Mosha, Taleghan, Peshva, and Firouzkuh, respectively. But clearly, in the return period of 2475 years in a period of 0.3 seconds, the contribution of seismicity of North Tehran fault increases compared to other faults. These diagrams show the role of distant springs in the changes of spectral acceleration values. In this way, the effect of the faults that are far away can be clearly seen in increasing the acceleration of the earthquake for long return periods and long periods.

Conclusions
The most challenging part of seismic hazard analysis is identifying seismic sources. The most important limitation for the description of seismic sources is the uncertainty in determining the location, geometry, size of the earthquake and the open distance of the occurrence of each source. Large earthquakes (Mw > 7) occur at intervals of hundreds to thousands of years. But the historical records of earthquakes in these areas go back to 1830 AD Masha fault. The proper identification of the epicenter of the earthquake was not possible until the beginning of the 20th century, when the recording of earthquakes began. Therefore, the foci of historical earthquakes were identified based on the severity of damage to the structures. The rupture of smaller and deeper earthquakes does not appear on the surface of the earth. Large, shallow crustal earthquakes generally cause surface ruptures, but due to the lack of understanding of the earthquake mechanism, the ruptures of those earthquakes are not well documented. Fault slip in prehistoric and historic earthquakes can be estimated through paleoseismological studies. Therefore, in this study, while examining recent paleoseismological studies, the geomorphic evidence of past earthquakes was determined. Also, the statistics of historical and prehistoric earthquakes in all the faults of the region were accurately identified. Then, the Probabilistic Seismic Hazard Analysis (PSHA) has been performed using recently published data and information. A shallow crustal fault model has been used to estimate seismic hazard using the recently published Ground Motion Prediction Equations (GMPEs). Epistemic uncertainties have been calculated using the logical tree approach. The value of spectral acceleration was estimated for the return period of 475, 975, 2475 years in PGA periods of 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.75 and 1.0 seconds. In these calculations, the shear wave velocity map of the region has been used for the first time.

Abstract 1. Hamed Alianpour, Department of Applied Geology, Faculty of Earth Sciences, Kharazmi University, Tehran, Iran.
2. Saeid Asiabar, Azad university
3. Maryam Dehbozorgi, Professor of Geologyy, Faculty of Geology, Kharazmi University, Tehran, Iran
4. Reza Nozaem, Professor of Department of Geology, University of Tehran. Iran
5. Nasim Ramezani, Faculty of Geology, Kharazmi University, Tehran, Iran
1-Introduction
Determining the anomalies resulting from active tectonics in rivers using geomorphological indices is very useful and can be associated with revealing active structures in the region. The evaluation of structures and landforms throughout their history of occurrence is the main subject of tectonic geomorphology (Shum et al., 2002, 276). The study of active tectonics is of great importance in assessing geological hazards, which is doubly important in areas with intense tectonic activities in the Holocene and Pleistocene (Ramazan et al., 1402)
2-Materials and methods
In this study, using Arc GIS software and a digital elevation model of 30 meters using the Strahler method, watersheds were divided and extracted. Then, by using topographic maps on a scale of 1:25000 and geological maps on a scale of 1:100000 and aerial photos on a scale of 1:20000 and through the Arc GIS software, different application layers including waterways, basins, faults, lithology and lines height, was prepared and finally, in order to carry out the present research in the area of Western Alborz and Azerbaijan, the studied area was divided into 50 basins and the value of the normal slope index was calculated for all parts of the main and secondary waterways and divided into 5 categories, then with Drawing the longitudinal profile of the longest river of each basin in MATLAB software, the numerical value of this index and the concavity index were calculated separately for each basin. Also, the Knickpoint extraction of a fault was carried out due to the sudden changes in the slope of the river in collision with the main faults, in order to investigate the tectonic activity of the region. Finally, the geological units and main structures of the region were examined and analyzed with the results of the longitudinal profile of the river and field observations.
3-Results and discussion
The results of quantitative investigation of changes in the longitudinal profile of the river and extraction of river channels in 54 drainage basins indicate high tectonic activity in the central and northern parts of the study area in the Bisotun-Taqebistan, Sahneh and Mianrahan faults. The normal slope index (Ksn) and concavity () calculated using the longitudinal profile and in the MATLAB software; indicate that the high values ​​of these indices show good agreement with the known faults of the study area. Using the values ​​of the normal slope index in the entire study area, the Ksn map of the region was prepared using the IDW interpolation method for the entire region. According to this map, the southern parts of the region, including the areas around the Bisotun-Taqebistan, Menghlat and Peru faults, show almost the highest value of this index. Also, the southern branches of the Mizanrahan and Qeshlaq faults have high values ​​of this index. The areas between the Sahneh and Mizanrahan faults, the areas between the Morvarid and Qeshlaq faults, and the southwestern parts of the region have the lowest values ​​of this index. In this study, the river breaks in the study area were extracted using a new method and then separated from each other according to the factors affecting their formation. In this method, the river breaks located in the longest river of each basin were extracted using the longitudinal profile obtained from the digital elevation model of each basin in the MATLAB software (Kirby et al., 2007). The data are processed and modified by the software and then the river breaks are extracted using the longitudinal profile of the river. Also, unlike the old methods, the river breaks of rivers with a length of less than 10 km can be extracted. A high percentage of the extracted river breaks are related to faults in the study area, which can indicate the possible effect of faults on changing the slope of the riverbed and their recent activity. In the southernmost part of the study area, several river breaks have been created by the action of the Kooh-e-Safid, Shirazi, and Sarab faults. The presence of numerous river breaks in the basin of the Bisotun-Sahneh thrust at the intersection of the fault with the river indicates the possible recent activity of these faults. Numerous river breaks in the central parts of the Bisotun-Sahneh thrust, near the village of Chalabeh, as well as the increase in the normal slope index of the river in contact with the fault in this area indicate the greater activity of this part of the fault .
4- Conclusion, Keywords
- Current very high and high tectonic activity in the Bisotun-Taghbostan thrust zone and the Sahneh-Morvarid fault zone as part of the Zagros Main Fault (MRF) and moderate and relatively high activity in the Mianrahan fault and the Kooh-Safid fault zone as a branch of the Zagros Thrust Fault (ZTF) in the study area based on the results of quantitative analysis of the longitudinal profile of the river and the extraction of the river break.
- Acceptable correspondence of the occurrence of earthquakes with the level of tectonic activity based on changes in the longitudinal profile of the river as initial studies to identify seismically active areas and long-term earthquake forecasting in areas with high tectonic activity.
The visited Raba and finally the tectonic activity of the area were analyzed and evaluated.
Keywords: Active tectonics,longitudinal profile of the river,Rudshekan,Sanandaj-Sirjan,Active tectonics

Abstract 1-Introduction
Spectral acceleration zoning is a critical tool for evaluating structural response to seismic events and plays a key role in both seismic design and regional risk mitigation strategies.
Tehran, located on the southern flank of the Central Alborz range, lies in one of the most seismically active areas of the Middle East, shaped by the convergence of the Arabian and Eurasian plates. Major active faults such as the North Tehran and Mosha faults dominate the tectonic framework.
However, recent Quaternary tectonic and morphotectonic studies have questioned the seismogenic nature of previously identified faults like North Rey, South Rey, Kahrizak, and Eshtehard, suggesting they may instead represent relict paleoshorelines of the ancient Lake Ray (PAMELA), rather than active tectonic sources (Berberian, 2014; Berberian & Yeats, 2016a; Jarahi, 2021a; Navar Noveiri, 2021; Navar Noveiri et al., 2021; Nazari et al., 2010). This study aims to improve Tehran's seismic hazard models by removing non-tectonic features and integrating reliable paleoseismic data. It focuses on refining ground acceleration estimates and comparing them with previous models, including Standard 2800, EMME, and GSHAP.
Materials and methods
This study presents a comprehensive Probabilistic Seismic Hazard Assessment (PSHA) for the Tehran metropolitan area, based on a revised seismotectonic model that excludes faults lacking credible geomorphological and sedimentological evidence of tectonic activity. The methodology includes four core steps: (1) definition of seismogenic sources, (2) selection of regionally calibrated Ground Motion Prediction Equations (GMPEs), (3) development of a logic-tree to address epistemic uncertainties, and (4) computation of ground-motion exceedance rates. The seismotectonic framework was developed using prehistoric, historical, and instrumental earthquake data from IRSC, IIEES, and ISC Bulletin. Faults such as Eshtehard, North/South Rey, and Kahrizak were excluded based on paleoseismic evidence. The analysis focused on major active faults like North Tehran, North Karaj, Mosha, Taleqan, Firouzkuh, and Pishva.
Ground motion was modeled using NGA-West2 GMPEs, calibrated with local data and integrated into the logic-tree with appropriate weighting. PGA and spectral acceleration (SA at 1.0 s) were computed using Ez-Frisk software for return periods of 475, 975, and 2,475 years. Soil classification was based on Vs30 categories per the fourth edition of Iran’s seismic code (BHRC, 2014).
3-Results and discussion
Tehran’s strategic and demographic importance has made it a key target for seismic hazard mapping efforts. This study’s findings warrant comparison with previous national and international assessments. Although Standard 2800 remains the main reference for seismic design in Iran, its hazard zoning map has seen little change. The current study reveals that the standard overestimates ground acceleration in Tehran, with actual values ranging from 0.1 g to 0.3 g, compared to the code’s fixed 0.35 g and 0.3 g contours. The Global Seismic Hazard Assessment Program (GSHAP) was launched between 1992 and 1999 with the goal of producing comprehensive global seismic hazard maps (Giardini, 1999). Updated versions were later released (Giardini et al., 2013). According to GSHAP data, peak ground acceleration (PGA) values across the Tehran metropolitan area and its surrounding plain range from 0.2 g in the southern parts to 0.5 g in the northern sectors. The Earthquake Model of the Middle East (EMME) project was launched with the aim of providing the most up-to-date seismological insights for the Middle East region and has been regarded as one of the most reliable sources for seismic hazard analysis in the area (Zare et al., 2014). According to the findings of this study, earthquake ground acceleration values in various parts of Tehran and its surrounding plain range from 0.4 g to 0.75 g. One of the most credible and recent seismic hazard studies conducted in Iran, with the involvement of international experts such as Professor Yousef Bozorgnia is the work by Gholipour et al. (2008). The results from the first phase of that study, covering return periods of 475, 975, and 2,475 years, were compared with the findings of the present research for the corresponding study area.
The modeling results indicate that in certain southeastern areas of Tehran, the design peak ground acceleration (PGA) estimated using the optimized logic-tree structure is approximately 0.05 g lower than that suggested by national reference models. According to structural engineering assessments, such a reduction in PGA corresponds to an 8–10% decrease in seismic design loads (FEMA, 2012).
In typical retrofitting projects, this change could result in an average cost reduction of 150,000 to 200,000 IRR per square meter of floor area (ASCE, 2003). For instance, in a building with a 2,000 m² footprint, this would translate into a savings of approximately 300 to 400 million IRR. Thus, employing a refined seismic hazard model can contribute not only to safer structural design but also to the economic optimization of construction and retrofitting efforts.
4- Conclusion

The proposed model improves seismic hazard estimates for Tehran and offers a framework for revising models in similarly situated cities. By excluding inactive faults like those in southern Tehran, the model reduces uncertainties and increases the accuracy of spectral acceleration maps. These results support updates to seismic design codes, urban planning, and retrofitting priorities in high-risk areas, especially southern Tehran.

Abstract Abstract
Determining and studying the crustal strain tensor allows describing geodynamic processes such as stress accumulation, which is an important parameter in seismic hazard assessment. In this study, the geodetic strain rate for the Western Alborz and Azerbaijan regions was calculated using geodetic data and the finite element method. The results of the geodetic strain calculation for the Khoy region show a right-lateral strike-slip shear in the NW-SE direction along with a compressional component. In the northern area of Tabriz, these results show a right-lateral strike-slip shear with a compressional component in the E-W direction in the area around the GhoshaDaghi fault. In the Western Alborz region, the results obtained from the calculation of geodetic strain for the eastern part of the range to the westernmost part of the Rudbar fault show a left-lateral strike-slip shear along the WNW-ESE direction with a tension perpendicular to the structure of the region. The magnitude and direction of the velocity vectors in the northern and southern parts of the western mountain range show a right-lateral strike-slip shear with a tension perpendicular to the mountain range.
Introduction

Calculating and examining geodetic strain as the current active deformation at the surface of the Earth's crust in a region and comparing it with seismic deformations or focal mechanisms of earthquakes occurring in the deep parts of that region as well as deformations in surrounding areas can be helpful both in better understanding active tectonics and in assessing the risk of future earthquakes.
This paper is dedicated to comparing tectonic deformations recorded by geodetic surveys in three separate regions of khoy, Varzaghan, and Rudbar in Iranian Azerbaijan and Western Alborz. Large strike-slip faults and rough mountains are common features of the study areas, and all three areas are directly affected by the northward movement of the Arabian plate and its interaction with the southern Caspian backstop (Solaymani Azad et al., 2019). Seismic hazard is one of the main problems of the study areas, as demonstrated by recent large earthquakes. Since Iran is currently covered by a GPS geodetic network, it is possible to calculate the geodetic strain rate tensor and compare it with seismic strain rate tensors or focal mechanisms of earthquakes that occurred in the region.

Research Method
In this study, the Delaunay triangulation method and geodetic velocity vectors were used to calculate the geodetic strain rate, and the planar velocity gradient tensor was calculated separately for each triangle. In order to calculate the geodetic strain rate tensor and estimate the kinematics of the study area, GPS data published in the article by Khorrami et al. (2019) were used. The velocity vectors used in this study are relative to the Eurasian frame.
The study area was divided into 12 triangular grids in the Rudbar region, 16 triangular grids in the Varzaghan region, and 14 triangular grids in the Khoy region. A GPS station is located at the vertex of each triangle.
Based on the hypothesis that the velocity field v varies linearly within each triangular subnetwork spanning the GPS network, we calculate the average horizontal velocity gradient L = grad(v) on each triangle. Since the velocity gradient generally incorporates both deformation and rotation, this two-dimensional tensor is asymmetric. L can be separated into a symmetric and an antisymmetric part as follows:

Its symmetric part is the strain-rate tensor while its antisymmetric part provides a local measure of the rigid rotation rate (Malvern 1969).

Discussion and Conclusion
To estimate the kinematics of the study area, GPS data published by (Khorrami et al., 2019) were used. The velocity vectors used in this study are relative to the Eurasian fixed frame.
The results obtained from the geodetic strain calculated for the Western Alborz region as well as the velocity vectors used show a left-handed shear in the WNW-ESE direction in the eastern part of the studied area. This left-handed shear is accompanied by a NNE-SSW stretch due to the divergence of the axes of minimum elongation (e2). In the west of the Western Alborz region, the direction of the velocity vectors obtained for the north of the mountain compared to its south shows a right-handed shear in the WNW-ESE direction. The amount of geodetic strain also decreases from east to west and the elongation axes show smaller values. These results are in good agreement with the effects of the interaction of the South Caspian basin on the Arabian-Eurasian convergence in the NNW area of Iran (Soleimani Azad et al., 2019).
Also, according to the results obtained from the calculation of geodetic strain and velocity vectors plotted in the northern region of the North Tabriz Fault, a dextral shear with an approximately east-west trend is visible in this area. Considering the location of the Ghosha-Daghi fault zone (which passes through the middle of this range), it can be related to the function of this fault. This dextral shear is accompanied by its pressure in the WNW-ESE direction, considering the convergence of the axes of minimum elongation (e2) obtained from the geodetic strain calculations. These results also have a good agreement with the tectonic transpression proposed by many researchers in the NW area of Iran (such as; Jackson, 2002; Soleimani-Azad et al., 2015). The geodetic velocity vectors plotted in the functional area of the Siyeh-Cheshme-Khoi fault and its surroundings show a clear dextral shear with a NW-SE trend for this range. This dextral shear is associated with a NNW-SSE orientation due to the convergence of the minimum elongation axes (e2). All velocity vectors obtained from GPS stations located in the northeast of the study area show a clockwise rotation relative to the stations in the southwest of the area, indicating dextral shear in this part of the study area. The Gilato-Siyeh-Cheshme-Khoi, Chaldran and Mako faults, which have a northwest-southeast trend, are located in this zone and each of them could be responsible for attenuating a part of this dextral shear.

Abstract Introduction
The Eastern Anatolia–South Caucasus–NW Iran sector of the Alpine–Himalayan belt hosts numerous Quaternary volcanic centers amid intense seismicity. This paper quantitatively evaluates how transtensional strike-slip structures control the location and timing of volcanism—an issue that, despite abundant Holocene and historical eruptions, has rarely been tested. The central hypothesis posits that releasing step-overs and pull-apart basins exert first-order control on Quaternary volcanism. Representative cases (Ararat, Tskhou–Karkar, Porak, Sabalan) provide archaeological and ^14C evidence for extension-guided eruptions.
Methods
(1) Remote sensing & vent inventory: Visual interpretation of QuickBird (0.6 m; 2002–2006), Corona KH-4B (2.7 m; 1967–1972), and Landsat-7 ETM+ (30 m; 1999–2003) identified macroscopic volcanic units (cones, maars, shields); clusters <1 km were treated as single centers. Positional uncertainty is ~±100 m; field/Google Earth Pro validation at 45 sites yielded ≥92% accuracy. A total of 820 centers were mapped.
(2) Seismic catalog: Historical sources plus ISC (1900–2020) and NEIC (1964–2020) were merged, duplicates removed, and magnitudes homogenized to Mw. Completeness (Mc) was determined by maximum curvature; a and b parameters were estimated via Aki–Richards (uncertainties ~±0.1 for Mc and ±0.05 for b).
(3) Random baseline & statistics: 10,000 random points (excluding lakes/glaciated highlands) provided the null model for vent–fault distances. We applied 10,000-trial permutation tests at p<0.001, two-sample K-S tests for distributions, and t-tests for means. All computations used Python/SciPy v1.10.
Results
(1) Proximity to active faults: The mean vent–fault distance is 6.3 km, significantly smaller than the random expectation 9.5 ± 0.7 km (p = 1.0×10⁻⁴), implying ~34% reduction relative to a random field.
(2) Structural focusing: Vent densities peak within releasing step-overs and pull-apart basins. Three standout clusters are: Ararat–Sevan–Syunik corridor, Van–Erciş–Patnos (Nemrut–Süphan–Tendürek), and the Tabriz–Sahand–Sabalan system. Density lobes align with NW–SE strike-slip traces, whereas compressional bends show depleted vent densities.

(3) Within-cluster statistics: Inside KDE90, vents average 2.94 km from the nearest fault (n=23), versus 6.64 km outside (n=207); the 3.69 km difference is significant (p = 0.00120). Spearman’s ρ between the KDE score and fault distance is negative (r ≈ −0.234).
(4) Temporal coupling: Holocene/historical eruptions broadly coincide with Mw≥5 earthquake clusters; the A.D. 1840 Ararat event (~Mw7.4) with explosive activity on the northern flank is emblematic. Catalog parameters Mc ≈ 3.0 and b ≈ 0.95 are consistent with active strike-slip belts.
(5) Case studies: Ararat’s aligned vents/young flows, Holocene lava generations at Tskhou–Karkar, ^14C-dated historical activity at Porak (~1100 BCE), and geochemical/hydrothermal indicators at Sabalan collectively substantiate an extension-guided magma ascent.
Conclusion
Strike-slip systems with an extensional component act as a gate valve regulating magma ascent and eruption timing. The statistically significant spatial focusing of vents near active faults and temporal synchronization with regional seismic clusters reveal a coherent tectono-volcanic pattern. Practically, volcanic hazards constitute a substantial share of regional risk alongside seismic hazards, advocating integrated seismic–volcanic monitoring and stress modeling to refine hazard assessments for NW Iran and the South Caucasus.


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Abstract 1-Introduction
Geology refers to tectonic processes that create changes in the earth's crust during a time scale. Most transformations are important for human societies. Studying the geology of an area is very important in assessing the risk for that area, especially in areas where the amount of tectonic activity during the Holocene and Upper Pleistocene is high, these studies will be important. Although tectonics is the gradual breaking of the earth's crust, which may damage human-made structures, but most of the processes that cause sudden events are important. Based on this, knowledge of the terrain-structure in a region can reduce the risks of sudden events (such as earthquakes) (Keller & Pinter, 2002).
The surface rupture zone of an earthquake fault is defined as the distance from the fault where all structures and facilities face the direct risk of structural rupture, regardless of their vulnerability. Based on this, any type of facility and structure, with any degree of retrofitting, will not be able to deal with surface cracking, and there is no option other than changing the location of the structure for the safety of the structure (CDC, 2002).
The purpose of this research is to investigate the evidence of active tectonics and activity of the Kundaj fault in the Quaternary, which will be done through field observations of trenches in the alluviums and alluvial cones of the investigated area, and it will be tried to clarify the location of the Kundaj fault in alluvial areas.

2-Materials and methods
The investigated area covers the distance between the city of Abek and Qazvin, and in this area, the evidence of the activity of the Quaternary Kundaj fault has been examined. The location of the Kundaj fault is shown on the geological maps in Figure No. (1). As can be seen in the map the Kundaj fault has been identified in a small area and its approximate length is 4 km, and in the 1:100,000 map, the approximate length is 30 km. This fault has been taken into account, and about 9 km of it has been determined, and the rest of the length of the fault, which passes through the Quaternary alluvial zone, is a dashed line, and its exact location is not known. In this research, the location of the fault has been identified and verified.
The research method in the current study is based on library studies and field observations. In this regard, the information related to the geological and geo-structural situation is examined in a library form, and then the evidence of faulting in Quaternes alluviums is discussed in relation to the field investigations. After completing the geological information, evidence of faults and studies of Quaternary alluviums and location of evidence of fault activity, data analysis has been done. Finally, by analyzing the results of the comparison of investigations and evidences of fault and Quaternary activity, the position of Kondaj fault and its Quaternary activity are evaluated.

3-Results and discussion
On the geological maps with a scale of 1:250,000 and 1:100,000, in most parts, it was displayed with a dashed line or it was hidden under the alluvium. This fault has cut Quaternary alluvium in many parts of its length. To determine the location of the fault in the alluvium, it is necessary to dig a trench and prove displacement in the Quaternary alluvium. Therefore, in this research, due to the impossibility of digging a trench due to its high costs, field visits were made to all the north-south waterways located along the fault. More than 50 large and small north-south watercourses cut the fault line, among which there are larger watercourses that have been dug in the bottom of the watercourse due to the high volume of water and intact walls of the watercourse trench where different layers of alluvium can be seen. They were selected for the field visit, the number of which was 8 waterways. Among these waterways, some of them have no evidence of faults and it was not possible to pick up the traces of fault activity in them. Only in three cases of waterway trenches, evidence of faulting and its activity was observed, which will be explained below.
As a result of the investigations, the traces and evidences of fault activity were investigated in three cases of waterway trenches, including the waterways of Behjat Abad, Jezmeh and Falizan villages, and evidence of fault activity, including cutting of alluvial layers and their displacement, was observed in 11 points, and the slope of the fault plane was measured. Various values were measured from 27 degrees to 56 degrees to the north, according to the location of the investigated locations, the average slope of the Kondaj fault plane was about 48 to 55 degrees to the north, and the measured slope of the fault plane was about He attributed 27 to 36 degrees to the branch of the fault. In the south of Behjat Abad village, a case of a fault spring was also observed, which is a proof of the fault zone in the mentioned area.
4- Conclusion
According to the field observations, the location of the fault in the Quaternary alluviums of about 11 km in the south of the villages of Behjat Abad, Tashe Abad and Jezmeh was corrected according to the geological maps, which is shown in Figure No. (19). In the 1:100,000 geological map of Qazvin, the Kundaj fault is located on the border between the Eap6 and Eab6 units with alluvium, and the location of the fault within the Quaternary alluvium was verified by field observations. In the rest, the length of the fault is 3.5 km from Dar al-Soror village to the east and 9.5 km from Khazinabad village to the vicinity of Anjilaq village. The results of the investigations are consistent with the position determined for Kundaj fault in the geological map. In the field investigations, the average horizontal and vertical displacement of the fault was measured as 22 ± 5 and 32 ± 5 cm, respectively.

Abstract Introduction
One of the tools for identifying landforms is the use of morphotectonic indicators, the use of these indicators is useful for studying areas that have experienced rapid uplift or tectonic transformation. Longitudinal profile of the river is one of the basic components in the river system and as a key topographical index it shows useful information of lithological, tectonic and erosion changes. The river system is a complex reaction process system in which various variables can play a role in its control, and any change in one of these variables causes the complexity of changes and adjustments in the river system. In geomorphological studies, the longitudinal profile of a river is used as a measure to detect tectonic uplift and changes in rock units, the longitudinal profile of rivers that are in equilibrium is concave, but various factors, including structural factors, change the longitudinal profile of the river . Abnormality in the longitudinal profile of the river, if it is caused by tectonic factors or lithological changes, can cause sudden changes in the slope and is associated with the creation of a kinck point, which can be seen as a waterfall and a rapid. Alborz is located on the southern margin of the Caspian and in the north of Iran. Considering that there are important rivers in the target area that reflect the tectonic conditions of the area and so far the mentioned methods have not been used for this study, the purpose of this study is to investigate the longitudinal profile of the river using MATLAB and GIS software in the area in order to Determining the level of tectonic activity of the main faults in the region.
Methodology
In this study, using Arc GIS software and a digital elevation model of 30 meters using the Strahler method, watersheds were divided and extracted. Then, by using topographic maps on a scale of 1:25000 and geological maps on a scale of 1:100000 and aerial photos on a scale of 1:20000 and through the Arc GIS software, different application layers including waterways, basins, faults, lithology and lines height, was prepared and finally, in order to carry out the present research in the area of Western Alborz and Azerbaijan, the studied area was divided into 50 basins and the value of the normal slope index was calculated for all parts of the main and secondary waterways and divided into 5 categories, then with Drawing the longitudinal profile of the longest river of each basin in MATLAB software, the numerical value of this index and the concavity index were calculated separately for each basin. Also, the Knickpoint extraction of a fault was carried out due to the sudden changes in the slope of the river in collision with the main faults, in order to investigate the tectonic activity of the region. Finally, the geological units and main structures of the region were examined and analyzed with the results of the longitudinal profile of the river and field observations.
Results and Discussion
The results of a quantitative study of changes in the longitudinal profile of the river and Knickpoint extraction in 50 drainage basins indicate high tectonic activity in the studied area, especially in Sangavard faults, other faults in the south, southeast and southwest of the region. . The index of normal slope (Ksn) and concavity () which was calculated using the longitudinal profile and in MATLAB software; This means that the high values of these indicators show good coordination with the known faults of the region, including the Firouzabad-Majder fault in the studied area. Sangavard fault, based on the numbers obtained from the normal slope index (Ksn) and concavity (), is the most influential fault in increasing the amount of these indicators in the studied area.
In this research, Knickpoint zones were extracted using a new method and their relationship with the structures of the region was studied. Knickpoints are widely spread in the studied area. The correspondence of sharp and steep knickpoints near the base of the mountain with active faults in the area shows that most of them were created by tectonic activity. The effect of lithological features on the frequency and size of knickpoints can be seen in some places, but they play a secondary role after tectonic activity. In this method of extracting fault lines, the location of fault lines corresponding to Sangavard faults, Kiwi fault, Sheikh-Janlu fault, Qalban-Qiyeh fault and faults located in the south, southeast and southwest of the studied area overlap. They are significant with the index of normal slope and concavity. The conformity of the location of Knickpoints in the field observations with the results of softening also confirms the accuracy of the methods used.
The correspondence of the location of Knickpoints in the field observations with Knickpoints extracted by the method mentioned in the previous sections shows the accuracy of the method used. The tectonic evidences obtained from field observations also prove the recent tectonic activity of structures and faults in the region. The existence of landforms such as high alluvial , the creation of triangular facets, the tilting of layers, the creation of narrow valleys, and the existence of V-shaped valleys are in addition to the results of the morphometric indices. Geostructural evidences such as faulting and folding in Neogene and Quaternary units, displacement of Neogene units due to the activity of the aforementioned faults, thrusting of old units on young units, is a strong proof of the high activity of the structures related to the faults in the case.
Conclusion
High tectonic activity in the study area, especially in Sangavard, Niki, Andalibi, Sheikh Janlu, and Qalpan Qepeh faults and other southern faults of the region using quantitative analysis of the river profile and extraction of Knickpoint in MATLAB software and high agreement of the results of quantitative profile studies River with field evidence and seismic history as an acceptable method to identify areas with high tectonic quality.

Abstract The study area is located in the northeastern part of Isfahan province, within the Na’in county, between the Khur and Bayabanak regions, and Ardistan, on the 1:100,000 Anarak geological map sheet. It lies between geographical longitudes ‘30°53’ to ‘54’ and latitudes ‘30°33’ to ‘33’.
The study was conducted using satellite image processing techniques with Landsat 7 (Enhanced Thematic Mapper Plus - ETM+) and Landsat 8 (Operational Land Imager - OLI and Thermal Infrared Sensor - TIRS) sensors. The following techniques were employed:
1. Band Ratio: Used to mitigate topographic and shadow effects and enhance mineral visibility.
2. Normalized Difference Vegetation Index (NDVI): Highlighted vegetation in the area.
3. RGB Color Combination: Separated lithological units based on color.
4. Filter Applications (Sunangle, Highpass, Edges): Enhanced fault lines, boundaries, and sharp edges.
5. Digital Elevation Model (DEM): Utilized ASTER DEM at a 1:10,000 scale to create a 3D model of the region, enhancing visibility in valleys through shadow creation.
6. Principal Component Analysis (PCA): Reduced data dimensions while preserving information. This method was used for identifying geological faults using seismic or magnetic data.
7. Aerial Geophysical Data: Analyzed 7.5-kilometer data to examine the total magnetic field intensity map, determine the location and subsurface status of magnetic bodies, and identify magnetic lineaments and both visible and concealed faults.
8. GIS Layer Evaluation: Assessed and evaluated information layers obtained in the Geographic Information System (GIS).
9. Field Survey: Conducted field visits to familiarize with the study area, correlate available information with field observations, and accurately identify and differentiate lithological units and their relationships, especially fault zones.
Geological investigations, remote sensing, aerial geophysics in the GIS environment, and field operations within the study area revealed that the density map of fault lineaments significantly influences the erosion-deposition trend in the southeastern part of the region, particularly in areas of faulting. Further analysis of regional tectonics indicated that the final thrust faults control the regional tectonics.
Based on geological investigations, remote sensing, aerial geophysics in the Geographic Information System (GIS) environment, and field operations within the study area, it has been determined that the lineament density map significantly influences the trend of land loss in the southeastern part of the region. This map is particularly indicative of substantial variations in fault lineament density, especially in the faulted regions.
After examining the tectonics of the area, it was found that the final emplacement of faults controls the regional tectonics. According to calculations of fault slip potential, in each section of the regional faults, two faults—Shurab and Doldol—have the highest slip potential. In other words, the northeastern segment of the Doldol fault exhibits a higher seismic rate compared to other sections. Remarkably, recent seismic activities in the region have occurred primarily near the major fault zones.
The seismic rate gradually increases toward the northern terminus of the Jombay faults, while conversely, in the southeastern part of the region, the maximum slip potential is observed for the Turkmeni-Arba’id, Kuh-e Pol Khavand, and Baybank faults. Additionally, the Anarak fault experiences an elevated seismic rate toward its northern-southwestern terminus.
The active fault trends in the study area reveal a northwest-southeast pattern, consistent with data obtained from field surveys. Considering the average slip rates of regional faults in recent years and results from previous studies, the northern-southwestern segment of the Anarak fault (from Anarak to the Shurab fault in the Talmasi section) has been identified as an area with the highest likelihood of future sliding. The northern-southwestern half of the study area is associated with the most significant fault slip potential, and tectonic structures in the northwestern-southeastern regions represent the youngest neotectonic activities. Remote sensing data were effectively utilized to display lithological and structural alterations.
In the studied area, which includes 198 lineaments (from remote sensing studies) and 18 digital faults from the geological map of Anarak, with a length of over ten kilometers, as well as 9 probable magnetic faults, the majority of these lineaments are observed in the southwest region. However, these lineaments do not correspond to any fault features on the geological maps. The magnetic lineaments are well-aligned with the structural faults on the geological map, except for lineaments F-586, F-416, F-417, F-698, and F-701, which do not have any equivalent fault representation on the existing maps.
All 198 lineaments require field studies, and most of them are associated with alluvial deposits. These lineaments could potentially represent new geological features. A very high correlation was observed after overlaying the lithology map with the geological map.

Abstract 1-Introduction


Bandar Genaveh earthquake accured in the foredeep of Zagros, as it is one of the most active seismic belts of fold and thrust belt in quaternary (Etemad-Saeed et al., 2020). Major deformation in this zone is caused by the development of blind thrust which cause the growth of folds and the subsequent increase and intensity of orogeny (Berberian 1995). The main purpose of this research is to investigate the vertical surface changes associated with the earthquake using the Sentinel 1 satellite radar.
The area affected by the earthquake includes a series of double-plunge folds, extending northwest-southeast.This area is located on BolKhari anticline with the northwest-southeast extension as one of the surface deformations in the foredeep of the Zagros orogenic belt (Sanaei et al. 2019).

2-Materials and methods
In order to calculate the amount of vertical displacement during an earthquake, two radar images of the Sentinel 1 satellite with IW mode on April 14 and 26 have been used (https://sentinel.esa. int/web/sentinel/missions/sentinel-1). Each Sentinel 1 image has three IWs and each IW contains 9 bursts. The studied area is covered by IW3 and parts 6 to 8 of the obtained images. The extraction process of vertical displacement was done using SNAP (https://step.esa.int/) software.

3-Results and discussion

The output image of the displacement before and after the earthquake shows a surface change with a maximum vertical displacement of 16.5 cm and negative 0.9 cm from the satellite. In other words, the area affected by the earthquake has risen by 16.5 cm and subsided by 0.9 cm. These surface changes are observed in the form of an ellipse with a large diameter extending northwest-southeast and parallel to the Golkhari anticline and at the end of its northwest plunge. This displacement ellipse is spindle-shaped with the elongated part towards the northwest.
In order to investigate the changes in the vertical movement of the earth's surface, two profiles were drawn in the two directions of northwest-southeast and northeast-southwest, parallel to the major and minor diameters of the deformation ellipse A-B profile along the small diameter shows a subsidence along the northeast and asymmetrical uplift with a lower slope in the northeast and a higher slope in the southwest part. Profile C-D, which is drawn along the southeast-northwest direction and shows a slight subsidence at the southeast end and an asymmetric uplift with a greater slope in the southeast part.
In general, the following evidence can be evidence to the progress of the orogenic foredeep towards the southwest and northwest, or in other words, the growth of the Bolkhari anticline in the direction of the northwest caused by growth of a blind trust fault during Genaveh earthquake.
1- Displacement profiles show a subsidence in the southeast and northeast and an asymmetric uplift with extension to the northwest and southwest. This displacement can be seen as uplift along with the dextral movement caused by the thrust fault with the progress of deformation or rupture of the fault from the southeast to the northwest parallel to the axis of the anticline.
2- The highest uplift has occurred at the end of the northwest plunge of the anticline, which can be seen as evidence of the progress of this plunge towards the northwest.
3- The epicenter of the earthquake (USGS as a base) is in the northeast of the displacement ellipse and even other are located either in the southeast or northeast part and indicate the starting point of rupture from these parts to the south and northwest.
4- The most destruction and damages are related to the areas and villages located in the northwestern part of the anticline and in the area of the most surface displacement, which are well matched.
5- The dispersion of aftershocks shows their concentration on the area with the highest uplift. Other aftershocks with less concentration are scattered in the form of a crescent from the southeast to the northwest and on the northeast slope. This pattern of aftershocks can be an evidence of the existence of the main fault with the northwest-southeast extension with a slope towards the northeast, whose effect started from the northeast and continued parallel to the long axis of the deformation ellipse.
6- Almost half of the displacement ellipse is located beyond the mountain-plain border and in the plain's edge, which indicates the uplift of the plain, or in other words, the joining of these parts to the mountain front and the progress of a deformation front.

4- Conclusion
The radar interferometric analysis shows a vertical surface deformation with a spindle-shaped ellipse parallel to the Bolkhari anticline and with a maximum elevation of 165 mm along the northwest plunge of this anticline and on the border of mountains and plains. Comparing displacement ellipse with mainshock, aftershocks, surface destruction and mountain-plain boundary shows the uplift and progress of the mountain boundary towards the plain in the northwest and southwest with the growth of the Bolkhari anticline.

Key words: Zagros Front Fault, Sentinel 1, Bolkhari Anticline, Coseismic deformation, Blind Thrust, Quaternary deformation

Abstract 1-Introuduction
The Iranian plateau is located in the middle part of the Alpine-Himalayan orogenic belt, and it is one of the active regions of the world (Agard et al., 2005; Allen et al., 2004; Berberian and King, 1981). The Zagros orogeny was formed in the western part of the Iranian plateau by the closure of the Neo-Tethys Ocean and collision of the Arabian and Eurasia plates (Agard et al., 2011; Jackson, 2011; Berberian, 1983). The Zagros orogeny is subdivided into four major zones from the NE to the SW: the Urumieh-Dokhtar Magmatic Arc (UDMA); Sanandaj-Sirjan Zone (SSZ); High Zagros Belt (HZB) and the Simply Folded Belt (SFB) (Mohajjel and Fergusson, 2013). The study area around the Hamedan city is located in the Sanandaj-Sirjan zone, and the perpendicular component to the Zagros trend has caused the formation of major reverse faults.There are many faults in the south-eastern part of the Hamedan city and they generally have a reverse mechanism and some of them have entered the city at the NW termination. These faults include Siahkamar-Alavi, Yalfan-Arzanfood, Keshin-Simin, Tafrijan-Mangawi and Anglas-Varkaneh faults. Generally, no detailed structural and geomorphological study has been done on these faults. Therefore, the aim of this study is to investigate the morphotectonics evidences related to the southeast faults of the Hamedan city using the fractal pattern of the faults and measuring the morphometric indices and field observations.
 
2-Materials and methods
The data used in this study, to calculate the morphometric indices and fractal dimensions of faults, were the geological maps, digital elevation model (DEM) and field observations. To investigate the active tectonic associated with the south-eastern part of the Hamedan city, the ASTER digital elevation model (30-m resolution) have been used to drainage and basins extraction. Then, the study area was divided into 40 basins for calculating the morphometric indices. Then, the stream length gradient index (SL), hypsometric integral index (Hi), basin shape index (Bs), drainage basin asymmetry factor (Af) and transverse topographic symmetry index (T) have been calculated and the corresponding map were constructed. Then, these maps are combined using hierarchical analysis process (AHP) to construction a final map of relative tectonic activity.
3-Results and discussion
Fractal dimension diagrams of faults in four box of the study area are calculated as: Da=1.5724, Db=1.5428, Dc=1.6551, Dd=1.6864, De=1.8088, Df=1.6436. As a result, the fractal dimension related to box b shows the minimum value (1.5428) and the fractal value of box e shows the maximum value (1.8088). Therefore, it can be concluded that the amount of fractures has increased from the NE to the SW and a high density of faults is observed in the south and SE parts of the Hamadan city. According to the values obtained from Af index, 12 basins are classified in class one, 6 basins in class two and 22 basins in class three. Several basins in the eastern part and two relatively large basins in the northern and southern parts of the studied area are also classified in class one. According to the values obtained from Bs index, three basins are in class 1, five basins are in class 2 and 32 basins are in class 3, and the lithology of the region (slate and phyllite) may be effective in this classification. According to the values obtained from Hi index, in the study area, most of the basins, except for two basins in the northeastern part of the studied area, show low relative tectonic activity. Results of T index indicate that 13 basins are classified in the first class, 26 basins in the second class, and two basins in the third class. And most of the basins, especially in the central part, have high to moderate tectonic activity. The western basins of the region have high values of SL index, which shows the high tectonic activity of the region. Ten basins in the central and south-western parts of the study area are classified in class one, and most of the basins in the eastern half of the studied area are classified in class three with low relative tectonic activity. Based on the final map of relative tectonic activity, the eastern half and also the northern part of the study area show moderate to low relative tectonic activity and these parts are divided into class two and three. Most of the eastern half parts of the study area are classified in class 3 with low relative tectonic activity. The western half of the study area and especially the central, southern and southwestern parts are classified in class 1 with high relative tectonic activity.
 
4- Conclusion
There are several faults with a general NW-SE trend in the southern and southeastern parts of the Hamedan city, which have caused the deformation of the rocks in the study area. The density of fractures increased from the northeast to the southwest of the study area, and the highest density of faults is observed in the southern and southeastern parts of the Hamadan city. In the northern and northeastern parts, due to the presence of recent deposits, the density of fractures is low, indicating low tectonic activity. The field evidence of these faults and fractures are observed as the fault zones and numerous fractures. Also, the formation of asymmetric basins and thrusting of different units are other geological effects related to these faults in field observations. The Yalfan-Arzanfood fault with the reverse mechanism has caused thrusting of the andalusite-schist units and Cretaceous limestone over the slates. The NW termination of this fault has passed through the north-eastern part of the Ekbatan Dam and has caused deformation of the adjacent units of the dam. The Keshin-Simin fault has created numerous fractures with a relatively parallel pattern in the schist units. These fracture zones are more than one meter in some parts and reach several centimeters close to the main fractures. The north-western termination of this fault cuts the Hamedan city from the south-eastern side and there is a large concentration of population along this fault.

Abstract Qeshm Island, with an area of ​​1,486 square kilometers, is located at the southeastern end of the Zagros Belt and at the western end of the Strait of Hormuz. Since the tectonic era, it seems possible to assess the influence of neotectonics and fault dynamics on island morpho-tectonic deformation using basin tectonic indicators. In this research, five indicators are extracted and calculated using satellite images, geological maps, aerial photographs, and a digital elevation model (30 meters) using various software. The smoothness and asymmetry of waterways (AF), watershed shape index (BS), cross-topographic symmetry index (T), river meandering index (S) and their comprehensive evaluation are evaluated in model form (IAT)). It is an index to evaluate the degree of tectonic deformation in the basin, and the obtained results indicate the relative dynamics of various tectonic deformations on the island. Furthermore, based on the IAT index, 26 of the 44 subbasins belong to a very high tectonic layer, consistent with the number of faults, so more active tectonic deformation is observed in the western part of the island.

Abstract Introduction
The studied area is located in edge of southern Central Alborz between important faults of the north Tehran, Mosha, Taleghan, Ipak and Eshtehard and includes significant earthquakes. In this research, the tectonic activity rate of the region has been evaluated using geomorphological indicators.

Materials and methods

In order to assess the relative tectonic activity through the study area, sub-basins and stream network were extracted by using Arc Hydro Tools software (an extension of Arc GIS software, ESRI) based on the DEM and in turn, 23 sub-basins have been resulted. The active tectonic 5 geomorphologic indices were used as follow: Stream length–gradient index (SL), Asymmetric factor (Af), hierarchical anomaly index (Δa), concavity index and normalized steepness index.
 
Stream Length–Gradient Index (SL): The SL index indicates an equation between erosive processing as streams and rivers flow and active tectonics. The SL is defined by Eq. (1) 
SL= (∆H/∆Lr) Lsc.    (1)
 Where ΔH is change in altitude, ΔLr is the length of a reach, and Lsc is the horizontal length from the watershed divide to midpoint of the reach. The SL index can be used to evaluate relative tectonic activity.  The quantities of the SL index were computed along the streams for all sub-basins.
 
 Asymmetric Factor (Af): The asymmetric factor (Af) is a way to evaluate the existence of tectonic tilting at the scale of a drainage basin. The method may be applied over a relatively large area. Af is defined by Equation (2).
Af= 100(Ar/At)        (2)
Where Ar is the area of the basin to the right (facing downstream) of the trunk stream and at is the total area of the drainage basin. If the value of this factor is close to 50, the basin has a stable condition with little or tilting; while values above or below 50 may result from basin tilting, resulting from tectonic activity or other geological conditions such as lithological structure.
 
Hierarchical anomaly index (Δa): The hierarchical anomalies index is calculated based on the number of hierarchical anomalies expressed by Equation (3).
 
Hai→j= 2^(j-2)−2^(i-2)              (3)
Where i is the primary stream, j is end stream and Hai → j the number of hierarchical anomalies of each stream. The number of hierarchical anomalies has been calculated in Equation (4).
 
Ha_t= Σ (Ha_i →j × Ns_i →j)              (4)
 
Where (Ns_i → j) is the total number of streams entering the high-level streams. The index Δa is expressed by the following relationship.
 
Δa=Ha_t/ N₁                                     (5)
 
Where Ha_t is the number of the hierarchical anomaly and N₁ is the number of first-order segments of the streams.
 
Normalized steepness index and Concavity index: Flint’s empirical power-law defines the river profile in a steady-state: S=K_SA^-θ       (6)
Where S, Ks, A, and θ indicate the slope, the steepness index, the drainage area, and stream concavity, respectively. In addition, Ks and θ are directly computed by the regression analysis of the slope-area data. Further, a steady-state landscape demonstrates that erosion, incision, and uplift rates are equal and stable over time. Different empirical studies indicated a direct relationship between the values of the steepness index (Ksn) and the bedrock erosion rate or rock uplift rate in the steady-state of river systems.
 
K_S= (E/K)^{( 1/n)}                           (7)
 
Where E denotes the uplift of the bedrock and K indicates the erosion coefficient which relies on the climatic and morphotectonics conditions of the area. Finally, n represents a positive exponent which is associated with the predominant erosion process of the area.  In the present study, Ksn was normalized to a reference concavity θref = 0.45 these parameters were implemented to fit a steady-state stream power solution to individual river longitudinal profiles in Matlab (Topotoolbox). The best profile was obtained from the matching of the uplift rate (U = E) or erosion (K) and the predicted rate. Furthermore, normalized steepness and concavity indices were determined using the longitudinal profile of the river.
 

Results and discussion

In this research, 5 morphological indicators related to the river channel and drainage basin were calculated for each basin, and for each of the 23 sub-basins, the rate of tectonic activity was defined for each of the indicators. The indices represent a quantitative approach to differential geomorphic analysis related to erosion and depositional processes which include the river channel and valley morphology as well as tectonically derived features, such as fault scarps. We also evaluated the outputs of the morphometric analyses based on field-based geomorphological observations. Thus, these results are proved to be extremely beneficial to evaluate relative rates of active tectonics of this region. The values of morphological indicators show that the basins with high tectonic activity have a good match with the main faults of the region, such as North Tehran, Mosha, Taleghan and Ipak faults and show high correlation with observed landforms during the field investigations such as the fault gorges, Strath terraces, multiple elevated alluvial terraces and knickpoints.
 

Conclusion

 
In this study, geomorphic indicators were used to investigate the tectonic activity of the region and it was found that the studied region has high tectonic activity along the North Tehran, Mosha, Taleghan, Emamzadeh Davoud and Ipak fault zones.

Abstract 1. Introduction
Azerbaijan Plateau is a part of the Alpine-Himalayan fold and orogeny belt, which is located in a compressional regime and between Talesh Mountains, south of Lesser Caucasus Mountain, east of Anatolia, north of Zagros Mountain. The studied area has located in the geographical longitudes of 47° to 48° and latitudes of 38° to 39° in East Azerbaijan province. There are wide ranges of Plio-Quaternary basalts and andesite basaltic in the sheet of 1.250000 Ahar. These rocks are gray to black in color. They also are formed of lava flows with scattered sometimes prismatic structures on the Paleocene andesitic lavas or conglomerate, siltstone and red marl Pliocene.
2. Materials and methods
    After the field investigations, we were taken 30 fresh and unaltered samples. Then, they were prepared as a thin section, then go undrer petrographic studies with a microscope in the laboratory.  Finally, we selected 10 samples were sent to the Amdel laboratory in the Australia for chemical analyses by ICP-MS, and OES.  Consequently, the results of whole rock chemical analysis data, were processed by GCD-KIT software. Then, all data were interpreted by geochemical conditions of all analyzed samples and also with their tectonic environment in the area.
3. Results and Discussion
The studied area is a part of the lesser Caucasus mountain range with high deformation and seismicity, which has located in a crustal convergence in the northwest of Iran. This area has a faulted system and with active strike-slip faults (Kocyigit et al., 2001). These systems often coincided with previous crustal discontinuities and have been widely effective in generating Quaternary magmatic activities locally through pull-part zones (Shabanian et al., 2012; Avagayan et al., 2010). Almost all the Quaternary magmatism in the region has occurred due to the operation of these fault systems and in the tensile position of the continental crust. Therefore, active fracture and fault systems and even old hidden faults have played a major role in the occurrence of the Quaternary magmatism.
Volcanic rocks of the studied area are hyalo-aphanitic to hyalo-microlithic porphyry texture with large crystals of olivine, plagioclase and pyroxene. Also, porphyry, trachyte, intersertal and intergranular texture can be seen in these samples. These samples have the nature of basaltic, thrachy andesite, mojearite and dacite, which are located in a calc-alkaline range. These rocks are rich in LREE and depleted in HREE.
They also have enriched of Cs, Th, Pb and depletion of Ba, Nb, Eu, La. The presence of garnet in the source of magma can indicated the involvement of processes and crystallization of olivine, pyroxene, and plagioclase. In addition, metasomatism or contamination with enriched crustal materials (Menzies & Wass, 1983) leads to the abundance of LREE elements. Therefore, the metasomatized mantle can be a suitable origin for the magma of the studied volcanic rocks. Enrichment of elements Cs, Rb, Pb, Ba, LILE and depletion of elements HFSE (Nb, Zr) indicated the magma of subduction arc zones (Wilson, 1989). The negative anomaly of Nb, P, Ti, Zr and the positive anomaly of Pb are the characteristics of crust contamination of quaternary basalts (Wilson, 1989; Hofman, 1997). Negative Nb anomaly is characteristic of continental rocks and crustal involvement in magmatic processes (Hofman, 1997). Also, the negative anomaly of Ti and Nb in the normalized pattern with primary mantle composition can indicate magmas related to subduction (Pearce, 1983; Wilson, 1989). All the samples are in the range of intraplate basalts (Figure a10) (Mesched, 1986), and show the orogenic situation (Pearce et al., 1977). The studied volcanic samples are volcanic arc (Muller et al., 1992) belong to the continental arc after the collision (Groves, 1997).  Also, the studied samples show the origin of lherzolite garnet mantle and lherzolite spinel with a rate of 2 to 5% of partial melting.
The tensile positions of the continental margins are active, where partial melting has occurred due to pressure reduction and rupture of the subcontinental lithosphere. Its compressive force resulting from crustal collision and crustal shortening, thickening and uplift leads to disturbance of subcontinental lithosphere thermal levels in these regions. Therefore, it seems that since the Eocene, the post-collision regime (Omrani et al., 2008) and since the Miocene (Hasanpour, 2008) has been ruling in the Arsbaran.
4. Conclusion
The Quaternary volcanic rocks in the eastern part of Ahar area, include a set of basaltic, andesite basaltic and andesite with calc-alkaline nature. The special depletion and enrichment of rare earth elements, these rocks are very similar to enriched mantle magmas and OIB, which were formed in the volcanic arc environment after impact on the active continental margin. For these samples, the mantle origin is lherzolite garnet to lherzolite spinel with 1 to 10% partial melting. Also there were happened metasomatisms of subducting oceanic lithosphere fluids. The geochemical evidences show some degrees of crustal contaminations during magma ascent. This magmatism has occured due to the subduction and the system of faults and fractures of the region and the tension tectonic situation. This tension system in the active continental margin after the collision has led to a decrease in pressure and finally the pouring out of basaltic magma.

Abstract Abstract
In this article, the activity of FMP in Pardis region, southeastern part of Central Alborz, has been studied.Some of the most the most important active faults in the study area are Mosha, Telo Paien,Latian, Sorkhe Hessar, Eivanakai, Qasre Firozeh, Kowsar, Niavaran, Qebleh faults.Methods:
In this study, a theoretical model for evaluating FMP based on the relationship between the geometric properties of the fault and the regional tectonic stress field is proposed. It should be noted that the results of this method are consistent with past seismic records and current micro-seismic activity in the region, so this theoretical model is based on the relationship between the geometric properties of faults and regional tectonic stress field.
The main purpose of this study is to evaluate the FMP of the campus area in the northwest of Niknam Deh to the southeast of Chenark. Using structural data, in order to achieve the position of the main stress axes, in a large area of the study area .
Results and iscussion:
According to FMP calculations in each section, it was determined that Mosha, Latian and Niavaran faults have the highest Movement potential compared to other fault sections.
Conclusion
The results of calculations in each section show a good agreement with the frequency of earthquakes, so that the eastern part of the region has a higher seismicity rate than other parts and the eastern part of the region (between Mosha fault and Niavaran fault) It will have the highest probability of landslide in the future, while the southern part of Niavaran fault is associated with the highest amount of FMP and the tectonic structures of its areas are introduced as the youngest neotectonic activities in the area.

Abstract Introduction
Neotectonic studies the dynamic processes affecting the formation of the earth and the landscapes in it (Keller and Pinter, 2002). In this regard, morphotectonic indices can be used to study tectonic activity in a short time and be used in more detailed future research. Morphotectonics is the knowledge of the study of shapes and shapes created on the earth created by tectonic mechanisms and is interpreted to mean the application of morphological principles in the analysis of tectonic problems (Burbank and Anderson, 2012; Grohmann, 2004; Rangzan et al., 2003). Examining the drainage pattern, and the rate of digging and diversion of rivers provides important information about the expansion and structural evolution of the region (Keller et al., 1998). Pardis city in the Central Alborz tectonic zone is affected by main faults such as the Alborz faults, Mosha fault, and North Tehran fault. Today's earthquakes in Tehran province are a sign of the continuation of the pressure regime prevailing in the province, and the city of Pardis is no exception. The study area has not been studied based on the qualitative indicators of morphotectonics and remote sensing, so it is necessary to predict the conditions and changes in the future of this study. The general purpose of this study is to investigate the seismicity of Pardis city based on qualitative indicators of tectonics and remote sensing for the first time.
Study Area
Pardis city has geographical coordinates of 35 ° 44′22 ″ N, 51 ° 46′40 ″ E, which is located on the slopes of Central Alborz. The geological structure of the study area is studied under the characteristics of the south-central Alborz zone. The existence of multiple fault systems and drift, an outcrop of older rocks, and disturbance of stratigraphic order are the geological characteristics of this region so that in the vicinity of Eocene volcanic sediments (green tuffs of Karaj Formation), shale and coal rocks are formed. Shemshak belongs to the Upper Triassic and Jurassic periods.
Data Analysis
In order to make connections between structural elements such as lines and faults, remote sensing studies have been performed, such as automatic extraction of lines, fractures, and preparation of density maps of lines. ASTER satellite image was used to extract the lines linearly and a linear density map was drawn in Arc GIS software. Rockwork 2016 software has been used to analyze the orientation of fractures and lines as well as faults in the study area. Using Google Earth images and Corel draw software, some tectonic morphology indices such as cone coefficient index, triangular surface index, and canal displacement index have been measured. Using field operations, the geological units and the main structures of the region, which include faults and folds of the region, were investigated.
Results and Discussion
The scattering of the linear indicates that most of the areas that correspond to the faults of the region as high density and in most of the basins there are areas with high density. Changes in magnetic intensity in the study area from northeast to southwest have gradually decreased and the increase in magnetic intensity from south to northwest is due to the proximity of the northern regions to Damavand and the increase of intrusive masses in this region. The study of the risk of surface rupture in Pardis city shows that the bed of this city hosts important faults such as Pardis, Hesa, and Ferdows faults that have cut Quaternary deposits and unfortunately their privacy has not been observed. The earthquakes occurred under the faults of Rudehen, Pardis, and Ferdows. In this area, alluvial fans have been exposed to more destruction due to tectonic and erosive activities and have been removed from the ideal alluvial fan shape. Shows the position of triangular surfaces in the southwest and northwest of the study area at the fault line. Adaptation and comparison of the location of faults and waterway lines in most parts of the region indicate a change in the direction of the tributaries of the waterway network.
Conclusion
Among the important faults in the region are the Rudehen fault, Pardis fault, Ferdows fault, Hesa fault, and North Tehran fault. In addition, the Rudehen fault at a distance of three kilometers north of the city limits, the North Tehran fault, and the Mosha fault can be the causes of destructive earthquakes in this city. The qualitative value of tectonic morphological indices of Pardis city such as alluvial fan index coefficient, triangular surfaces, and sudden changes in the course of rivers indicate the performance of faults and are evidence of the active tectonics of faults in the region. Reinforcement of important buildings and structures such as bridges and highways and reconstruction of worn-out structures is a very important task and should be given priority.

Abstract The origin and geochemistry of the sediments that make up the Khuzestan plain as one of the key areas of southwestern Iran has always been discussed. Detailed geochemical studies of these sediments, in addition to determining their origin, can provide appropriate information about weathering, erosion, ancient tectonics and environmental pollution in the Khuzestan plain. In this research, after library studies, 276 different points for field surveys were determined with the help of satellite images. Sampling was done from designated points in spring and summer when soil moisture was minimal. The collected samples were sent to the Central Laboratory of Tehran Geological Survey for geochemical experiments after sizing by sieving device of Ahvaz Center of Geology. Findings from sediment granulometry studies show that most of the grains studied have bad to very bad sorting and contain about 70% of particles equal to and larger than silt. In addition, the findings of geochemical studies show that CaO, SiO2 and Al2O3 are the most abundant oxides in these sediments and Ti, Zr, V, Ce and La are also the most abundant by-products.
The classification of the sediments based on geochemical indicators shows that these sediments are mainly in the range of Vaki and iron-bearing shales. It is noteworthy that the sediments of this plain are enriched with elements such as As, Bi, Cd, Co, Cu and U, which need to be studied more closely. The results of the study of these findings show that the deposits of the Khuzestan Plain, often in a short time with a high-energy environment. These conditions are more evident in the northern part of Khuzestan province, which is often composed of larger grain particles than the southern parts of Khuzestan province. In addition, geochemical studies performed to determine the ancient tectonics of Khuzestan plain sediments show that the primary origin of these sediments were Continental Island Arc and Active Continental Margin, which corresponds to the Zagros tectonic conditions and can indicate the primary origin of this Sediments are from Sanandaj zone of Sirjan (especially in the northern parts of Khuzestan province). Environmental studies on the collected samples show that these sediments are in a warning state due to the presence of elements such as As, Bi, Cd, Co, Cu and U.

Abstract The environment has had a significant impact on prehistoric human life, he chose the right place to live according to the potential of the environment. Humans were not yet aware of the technological advances for serious environmental change, and one of the most important reasons for choosing a habitat was access to fresh water. This important factor for selection, in some cases, led to dissolution. Consecutive droughts have led to habitat abandonment and settlement collapse, and in other cases, some settlements have been completely abandoned or have a cultural break due to changes in river direction and floods. Qala-bon area is one of the areas that has been culturally interrupted due to flood sediments. A culture with a thickness of about one meter was identified, which indicates a break in this area...

Abstract The aim of this study is to present the modified Mercalli intensity map in a probabilistic way based on seismic studies in Mako Quadrangle. The studied area is located in the northwest corner of Iran. The occurrence of several destructive earthquakes and the presence of active faults indicate a high level of seismicity in this region. Based on tectonic earthquake surveys and b parameter values, all active seismic springs were identified and seismic parameters were calculated for them. Then the modified Mercalli intensity map was calculated using four reduction relations. The results showed that the maximum intensity is in the form of a strip with a northwest-southeast trend, which shows a good compatibility with the Igdeer and Blikglu faults. The present results are in good agreement with the intensity map of the earthquakes that occurred in the region.

Abstract Nazi salt dome is located in the border of high Zagros and folded Zagros in the northwest of Chaharmahal Bakhtiari province. This dome is affected by Zardkooh fault in the heights of Zard Kooh. The sequence of formations in the region includes Infra-Cambrian sedimentary rocks up to the present time The aim of this study was to investigate the active tectonics associated with Zardkooh fault and Nazi salt dome in Bazaft area in Chaharmahal and Bakhtiari province, using morphometric indices. Zardkooh fault is the border of high Zagros and folded Zagros. Zardkooh fault and Nazi salt dome are both exposed on the ground. In order to study the tectonics of the study area, the study area was first divided into 59 basins Then quantitative morphometric indices such as hypostometric integral index (Hi), drainage basin asymmetry index (Af), river gradient index (SL), basin shape index (BS), mountain front sinusitis index (Smf), relatively active tectonics index (Iat) has been calculated. In Hi index, 7 basins with active new tectonic activity, 21 basins with moderate tectonic activityand 31 basins with low tectonic activity were identified. Also in Af index, 18 basins with high and activetectonic activity, 21 basins with medium tectonic activity and 20 basins with low tectonic activity were determined. One high-activity basin, two basins with moderate tectonic activity and 56 basins with low tectonic activity were identified in the SL index. In BS index, 2 basins with active tectonic activity, 2 basins with moderate tectonic activity and 54 basins with low tectonic activity were identified. In Smf 16 index, the basin has active tectonic activity and the rest of the basins have low to very low tectonic activity. Relative activity index (IAT) in the study area indicates the presence of 3 basins with active tectonic activity, 26 basins with moderate tectonic activity and 30 basins with low tectonic activity are low. Based on the calculated indicators, the study area has different basin activities from medium to low. The data show that the activity of Zardkooh fault, the activity of the Nazi salt dome, large waterways in the region, and vegetation in the region have a significant impact on the activities of the region. The area has moderate to low new construction activity.

Abstract Two mechanisms such as horizontal and vertical principal stress can create different fractures and faults in the rocks. The first one is tectonic forces as a result of the motion of plate tectonics and the second one is buoyancy forces as a result of magmatic activity (Ruch et al., 2016). The Kuh-Sefid granite emplaced in the flysch rocks of eastern Iran, southeast of Taftan, and the central part of the Zahedan-Saravan granite belt has provided a good opportunity to study the influence of tectonics and magmatic activity in creating fractures in this region. This granite, metamorphic halo, and surrounding rocks have been affected by different fractures system. The main purpose of this article is to investigate the role of tectonics and the main faults in the emplacement of Kuh-Sefid granite and the creation of obvious lineaments in this mass and the surrounding rocks, which can be a suitable basis for further studies on this little-known area.
Materials and methods
In order to analysis of fractures and faults in the study area at the first, the system of fractures and faults in the intrusive mass and host rocks are extracted using remote sensing and satellite image processing. In this study, Landsat 8 satellite images with pass number LC08_L1TP_156041 were used to identify the lineaments. Then, using GIS, these structures were differentiated and categorized based on the orientation, regional maximum stress, and their cross-cutting relationship.
Results and discussion
The granite unite has several main north-south lineaments parallel to each other. In metamorphic units, based on the position of this unit in relation to the granite unit, these structures were divided into five equal parts that have different orientations. Lineaments analysis of sedimentary rocks (Flysch): Based on the position of this unit in relation to the granite unit, extracted lineaments were divided into nine equal parts and then the rose diagram of each part was drawn. According to the genetic relationship between fracture structures and the direction of maximum stress in the region (Angelier, 1989; 1991), long lineaments that have displacement along their length were considered faults and used to estimate the direction of the maximum principal stress in the region. Kuh-Sefid granite as the youngest geological unit in the region, the granite mass intruded into the sedimentary rocks and creates a metamorphic halo in them. The existence of systematic fractures of the main mass shows that it was affected by tectonic stresses after cooling, but it should also be noted that the rise of granite masses can cause vertical stress and related fractures in the host rocks. These features have provided a suitable situation to investigate the tectonic history of the region and the effect of the main faults and the rise of the granite mass on creating brittle structures such as fractures and faults. The data obtained from remote sensing studies and statistical analyses of lineaments and faults at a glance show relatively active tectonics affected by different phases in the region According to the obtained, data two-phase of deformation from old to new are suggested. D1: progressive phase, which with the direction of maximum northeast-southeast stress causes the development of northeast-southwest conjugate fractures, and then the activity of faults parallel to Saravan fault provided a suitable environment for the intrusion of granitic mass. Simultaneously with the intrusion of the mass, radial fractures have developed in the surrounding rocks. After cooling and creating a metamorphic halo, the continuation of stress along the same direction has caused conjugate fractures in the main granite mass. Subsequently, the newer phase D2 due to the active tectonics of the region, by creating north-south faults, cuts and displaces all the old structures and Saravan fault.
 Conclusion:
The extraction of lineaments of the Koh-Sefid granite, the metamorphic halo, and the surrounding flysch rocks show the role of tectonics and magmatic activity in creating of these structures. The study of cross-cutting relationships and the classification of faults and lineaments show two deformation phases in the region. The initial phase, which is proportional to the general stress along the northeast-southwest direction, is a progressive phase, and the final phase, in accommodates the active tectonic regime of the region, acting as north-south dextral strike-slip faults. 
 

Abstract Study of area (Golpayegan area) is located in the Sanandaj-Sirjan structural zone, which is one of the most dynamic tectonic seismic zones in Iran. Among the most important faults of Janba in the study area, we can mention Khansar, Hila, Narpalang, Boland Ab, Qara No, Bid Arab faults. In this study, a theoretical model is proposed to evaluate the Fault Movement Potential based on the relationship between the geometric properties of the fault and the regional tectonic stress field. This model by et al. (1997) Lee, and has been used to evaluate the mobility potential of major faults in the Hong Kong area. This parameter allows for the percentage of possible movements in the current tectonic regime (CTR) for all active faults in a range. It should be noted that the results of this method are consistent with past seismic records and current micro-seismic activity in the region, so this theoretical model is based on the relationship between the geometric properties of faults and the regional tectonic stress field. To evaluate the mobility potential of active faults in Golpayegan area in the northwest of Kush to the southeast of Bid valley, the structural zone of Sanandaj-Sirjan.
Methods:
 Structural data were collected in a large area of ​​the study area in order to achieve the position of the main stress axes. The equations of this model were used in 6 stations in the mentioned area. Finally, using the inversion method, the maximum maximum stress in each section was obtained separately and placed in the equations.
Conclusion:
According to the calculations, the motion potential of the fault in each section of the faults in the area was determined that the Arab willow fault has the highest movement potential compared to other fault parts, which according to the calculation of the mountain frontal maze index is well visible. Category 1 tectonics with high activity, other faults are in the pre-seismic stage. The results of calculating the potential of faults in each section show a good agreement with the frequency of earthquakes, so that the eastern part of the study area has a higher seismicity rate than other parts. Due to the average landslide velocity of faults in recent years and also according to previous studies and results obtained from the area and data from the calculation of fault potential values, the eastern part of the area (the distance between Arab willow fault and male leopard fault ) Has the highest probability of slipping in the future. The southern part of Bid Arab fault is associated with the highest mobility potential of the fault and the tectonic structures of its areas are introduced as the youngest neotectonic activities in the area.

Abstract Abstract
 
The Bafq-Baghin fault system is one of the major faults in Central Iran and parallel to the Kuhbnan fault in the northeast and the Rafsanjan fault in the southwest. This fault system, under the influence of the stress, is the maximum that results from the convergence of the Arabian plate towards Iran plate has a right-strike with a compression component.  The study area is located in central Iran and its southeastern part. In the last division of central Iran, this region is located in the Poshtbdam.
 
Methods
 
Using satellite images and related software and integration with field data, fault system components were identified and mapped. Morphotectonic relationships and formulas were used to analyze the tectonic morphology of the region. Active strike-slip faults, especially those on the mountain front, usually appear as separate sections. By processing satellite images of the region and based on the study of building parameters, geometric condition, tracking along the fault system, examining changes along the direction, motion and branching sub-structures along the system, it was determined that the Bafgh-Baghin fault-slip fault system is like most active faults. It is formed in separate pieces.
 
Results and conclusion
 
 By studies performed during the system, 60 fault pieces were identified. Bafgh-Baghin fault sections were examined for tectonic morphology, which is evidence that the Bafgh-Baghin fault system is adjacent. In the direction of fault sections, fault precipices have been formed, which in some cases, several-meter precipices were observed. Folds with strike-slip faults are usually stepped and sloping to the main cutting direction. The term en echelon refers to the arrangement of buildings in a linear zone, so that the folds or faults are parallel to each other and have the same tendency towards the direction of the linear zone. The naming of en echelon folds is based on the displacement of the right-slip zones that create them, so that right-slip faults create right-handed folds and left-handed right-slip faults create left-handed folds. Due to the right-slip activity of fault sections, some folds in the mountains have become right-stepped. Large amounts of Vf are associated with low uplift rates, ie low tectonic activity, in which rivers have relatively wide bottoms. Low Vf values refer to deep valleys in which rivers actively dig valleys and are usually associated with active tectonics and uplift. Mountainous fronts associated with active tectonics have sinusoids (Smf) between 1.6 and 1. Low-activity mountain fronts have sinusoids between 3 and 1.6, and inactive mountain fronts have sinusoids of about 3 to values greater than 5 because of high erosion and inactive tectonics. The low values of mountain front page maze (Smf) and the ratio of valley width to valley depth (Vf) calculated in the direction of fault plots indicate fault and tectonic faults of the region. Wherever the strike-slip fault becomes stepped or bends, due to the movement of the fault in these areas, it either suffers from divergence and tensile forces that lead to elongation and pull-apart basin, or suffers from convergence forces that result. They create compression and pressure in the basin. In the pull-apart basin, normal faults and subsidence are created and it is a suitable place for sediment accumulation. In the compressive basin, compressive ridges and inverse faults are formed. Due to the fact that Bafgh-Baghin fault sections have a strike-slip mechanism, where the pieces are placed relative to each other, pull-apart basins and compressive basins are formed between these fault sections. With the strike-slip activity of the fault sections, pull-apart basins have been created between some fault sections that are staggered relative to each other. In one of the pull-apart basins of the region, a fertile village called Khanaman has been formed on the southwestern front of the Bafgh-Baghin fault system.
 

Abstract The study area is located in Eshtehard plain and in front of the Alborz mountain range. Eshtehard and its surroundings are in the range of seismic faults such as ipak fault in the south and north Eshtehard fault in the north. In the past, based on the evidence and phenomena of earthquakes and historical earthquakes attributed to Sagzabad, in the alluvial zone of Jaroo Mountain in Eshtehard plain, linear phenomena accompanied by obvious precipices such as the scarp of the south of Eshtehard are among the fault scarp Have been categorized. In this study, based on the data obtained from paleoseismology, geomorphology, geoelectric characteristics presented in this study, it seems that the southern part of Eshtehard is not a sign of a fault, but the result of a fold in the Red Formation. It is high which shows the morphological nature of the southern part of Eshtehard, which was previously introduced as the southern Eshtehard fault. This fold is a simple curvature of the layers that has been achieved during the Late Cenozoic due to the shortening of this part of the Alborz mountain range.
Methods:
For conducting paleoseismological studies in the study area, tectonic morphological features, geophysical surveys (2 geoelectric and geomagnetic sections) were performed. Finally, a site in the east of Eshtehard was selected and 4 trenches perpendicular to the scarp were dug. Then, structural phenomena and sediment-stratigraphic deposits on the trench walls were separated and studied. In this paper, the results of trench studies are presented.
Conclosion:
The results of additional studies such as paleo-seismic studies (with excavation of 4 trenches) and geophysics (magnetometric and geoelectric), show that the layers, horizontal and without any signs of young faults in the trenches (maximum depth 4) M) that even rejects the possible lateral and hidden faults in the depths;Because if there was such a fault in the area of ​​the southern part of Eshtehard, the mapped deposits of the existing partition trenches would have to be deformed. This indicates the morphological nature of the southern part of Eshtehard, which was previously known as the South Eshtehard fault. Thus, attributing this scarp to an active fault does not seem correct. However, the question remains why and how the scarp was formed? Our field observations show that the deposits in the studied scarp are of marl genus and belong to the upper parts of the Upper Red Formation that have been exposed at the surface. The most logical justification for this is the formation of an open anticline. Geoelectric data in the west of Mokhtarabad also clearly show the existence of an anticline in the study area. Accordingly, the formation of a linear complication on marl sediments scarp can be justified by the tensions that generally occur in the outer parts of the folds.

Abstract Introduction
The vertical and horizontal movements of the Earth crust have caused extensive changes in surface phenomena, in the active tectonic regions. In order to measure some of these changes, morphometry analyses have been used to evaluation of the amount of tectonic activity. These analyses are useful tools for analyzing existing feature at the ground level and provide a proper understanding of the condition of drainage network, changes of mountain front and uplifting. The anticlines of the Zagros fold and thrust belt indicate some evidences of tectonic activity. The Ghalajeh anticlines is one of the folded structures in the Zagros fold and thrust belt. So, this study has focused on assessment of tectonic activity along the northeastern and southwestern of limbs of this anticline, using quantitative study and analytical hierarchy analysis of stream patterns. These analysis as an indicator of geomorphic systems can help us to understand the behavior of tectonically drainage basins.
Methodology
In this study, Google Earth images, digital elevation model (DEM) and GIS software have been used for extraction of drainage network pattern and divide of the area around the Ghalajeh anticline into seven basins. Then, the streams of each basin were ordered and the order and length of each stream were measured. The indexes of hierarchical anomaly (Δa), drainage density (Dd), drainage frequency (Df), bifurcation ratio (R), bifurcation index (Rb), direct bifurcation ratio (Rbd), crescentness index (CI), precent of basin asymmetry (PAF), basin shape (BS), basin length to mean width ratio (Bl/Bmw), mean length of first order streams (LN1), Hinge spacing (Hs), Hypsometry integral (Hi), for each basins was calculated separately and the obtained results were analyzed in the Spss software.
Results and Discussion
The Zagros fold and thrust belt is the result of convergence between the Arabian plate and Iranian micro-continent due to closure of the Neotethys Ocean and subsequent continent continent collision. This belt is composed of long and asymmetrical anticlines with NW–SE trend and most of these folded structures indicate asymmetric geometry (the steepest limbs are on the southwestern limbs). The rate of tectonic activity is not same in all parts of the Zagros fold and thrust belt, and the uplift and shortening rate on each anticline is different. These mentioned changes caused differences in the amount of morphometric indexes as the indexes related to the drainage network. The study of drainage network pattern of the study area exhibits three types of drainage pattern along the Ghalajeh anticline. The first is the dendritic drainage pattern which are usually observed in wide or circular basins (basins1, 4, 6, 7).The second cluster is a parallel drainage pattern that is usually seen in long and narrow basins, such as the basins 5, 2. The third category of these drainage patterns is a parallel - trellis pattern that is integrated from the parallel drainage pattern and trellis (basin 4). The surface outcrop of the southwest limb of the anticline are the Gachsaran formation and the quaternary deposits and the Asmari-Shahbazan and Aghajari formations and quaternary deposits cover the surface outcrop of the northeast limb. Because of, existence of the evaporative rocks (salt and gyps) in the southwest limb, erosional basins (basins 6 and 7) have formed (sensitive to erosion and weathering) along this limb. But in the northeastern limb, most of the rock units are made of thick layer of limestone and resistant to erosion. Due to the deep drilling and erosion in the southwest of the limb, the number of stream order 1 decreases and the index values LN1 are reduced and consequently the index of DF is decreased. The minimum and maximum value of Hat index is 185 (basin 1) and 527 (basin 5) respectively. Result show an increase in Hat values suggest increase in the number of low order streams (order1) which is connected to the upper order (4 or 5). The maximum and minimum calculated values for Bs and Bl /Bmw indexes are in the basin 5 in southwest limb and basin 3 on the northeast limb respectively, showing the straight relationship between these two indexes. Also, calculated values for Hi index indicate medium tectonic activity and low tectonic activity of basins. The basin 4 contains the highest number of R and Rb indexes while the basin 6 contains the minimum value of the R, the basin 2 shows the lowest numeric value for the Rb index.
Conclusion
The results show that there is a strong positive correlation between Bs-Bl/Bmw indices as a result of a direct linear relationship with coefficient 0.93. Also, positive correlation between the R - Rb indices, resulting in a direct linear relationship with the 0.93 coefficient. There is a negative correlation between the R-DF indices and a strong negative correlation between the Δa-Hs indexes. It can be concluded that the southwestern limb of the Ghalajeh anticline is more active than the northeastern limb, according to the index values obtained for each basin and correlation between these indexes. The basin number 6 and 7 in the southwestern limb and basin number 1 in the north northeastern limb are affected by the intensive erosional processes resulting from tectonic activity.

Abstract Earthquake is one of the natural hazards that has caused many casualties and financial losses all over the world over the years. This is the reason why earthquake risk analysis should be studied more seriously. Iran is located in one of the seismic regions of the world, the Himalaya-Alps belt, where many earthquakes occur every year. Arias intensity function, as one of the important earthquake parameters, helps in seismic risk analysis and can be used to estimate structure performance, slope stability, and liquefaction during earthquakes. In this study, along with the tectonic and seismological analysis of Khoi area in the northwest of Iran, earthquake intensity zoning was done based on the Arias method. Numerical values of Arias intensity for return periods of 475, 975 and 2475 years were prepared in the form of equipotential maps. In the analysis, the effect of Quaternary sediment changes was also considered. Quite evidently, earthquake intensity is affected by changes in shear wave velocity, apart from distance from the fault; In such a way that with the distance from the seismic source, in areas with high thickness of Quaternary sediments, it even increases. This issue tells the effect of geological conditions in the estimation of parameters related to earthquakes.