About Quaternary Journal of Iran

  • Country of Publication: Iran
  • Publisher: Iranian Quaternary Association
  • Format: Online
  • Online ISSN: 2476-5635
  • Publisher Code: irqua.2023
  • Frequency: Semannual
  • Publication Dates: Summer and Winter
  • Language: Persion (with English Abstract)
  • Types of Journal: Scholarly Journals
  • Open Access: Yes
  • Policy: Double-blind peer-reviewed
  • Review Time (Submission to Acceptance): 16 Weeks Approximately
  • Alternate e-mail: irqua2014@gmail.com , info@iranquaternary.ir
Plagiarism policy: Although this journal uses different methods and softwares "Hamandjoo" and "Hamyab" to review Persian texts, the main responsibility and all the legal consequences are officially on the corresponding author. 

Open access: Quaternary Journal of Iran is an open access journal which means that all articles are freely available without charge to the user. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles, or use them, with citing the reference, for any other lawful purpose, without asking prior permission from the publisher or the author. This is in accordance with the BOAI definition of open access. This journal provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.

Copyright:  The authors retain the copyright and full publishing rights without restrictions.

All articles sent to Quaternary Journal of Iran should be related to Quaternary sciences and rely on common proxies and methods in Quaternary sciences.

Titles and topics related to the publication:

1) Climatology and Quaternary climate reconstruction.

2) Quaternary climatic events.

3) Quaternary stratigraphy and dating.

4) Neotectonics in Quaternary.

5) Sedimentary environments in the Quaternary.

6) Paleogeomorphology.

7) Quaternary lakes, playas, loess.

8) Dendroclimatology and Dendrochronology

9) Quaternary natural hazards (droughts, sea level changes, ancient earthquakes, ancient landslides, etc.).

10) Historical, prehistoric and Paleolithic archaeology

11) Paleosoil research

12) Quaternary modeling

13) Laboratory methods in quaternary sciences

    https://creativecommons.org/licenses/by-nc/4.0/  

Facies and Evolution of Holocene Sedimentary Environments on Jarrahi River mega fan (Southern Khuzestan Plain)

Pages 267-282

https://doi.org/10.22034/irqua.2024.723485

Javad Darvishi Khatooni, Hameideh Norouzpour

Abstract 1-Introduction
The Lower Khuzestan plain, located in southwestern Iran, forms the southeastern extension of the Lower Mesopotamian plain. It borders to the west one of the most important estuaries of the Middle-east region, i.e. the Shatt-el Arab. Three major rivers (Tigris, Euphrates and Karun) flow into the Shatt-el Arab which debouches into the Persian Gulf nearby Fao (Fig. 1). The study of palaeoenvironmental changes in the Lower Khuzestan plain is challenging, because of its rich archaeological heritage. One of the most ancient civilizations, the Elamite Kingdom (2700–539 BC) was primarily centred in the province of what is now called modern-day Khuzestan. Changes in coastal configuration could have had a profound effect on the population occupying the Khuzestan region from Elamite time to present. In this study, the Holocene sedimentary sequence of the Lower Khuzestan plain is investigated to reconstruct the Holocene evolution of the coastline and plain.
The Lower Khuzestan coastline is today being shaped by a semi-diurnial mesotidal regime. The tidal range averages ca. 3–4 m along the coastline, increasing to 5–6 m in the Khawr-e Musa tidal embayment. Because of the gentle offshore slope, wave energy is very low. The tide-dominated coastline is fringed by a large tidal flat with a width up to 15 km, extending landward along the Khawr-e Musa tidal embayment. The vast intertidal area is bordered by supratidal salt marshes and clastic coastal sabkha''''s with saltpans. There is no freshwater inflow into the intertidal area, except in case of extreme river flood events. In the south, the Jarrahi river distributary fan system feeds the Shadegan marshes. The vegetation density (Typha and Phragmites) and extension of these marshes vary greatly, as a function of the seasonal rainfall regime. The Holocene sequence of the Lower Khuzestan plain in southwest Iran has been investigated in the context of coastal evolution and relative sea-level change.

2-Materials and methods
For the stratigraphical investigation, 11 cores were collected manually. The coring was carried out using a gouge auger to obtain undisturbed and continuous cores to a depth of 5–10 m below the surface. A spiral auger was used to penetrate the compact clay layers. Borehole locations were registered using GPS. The surface elevation of the boreholes was inferred from topographic maps and sitespecific measurements obtained at the regional topographic institute. In the field, the cores and outcrops were described on lithology, sedimentary structures and macrofossils and preliminary facies identification was made. Samples were taken for laboratory analyses when significant changes in color, texture or lithology were observed. A further interpretation of the different depositional (sub) environments was carried out on the basis of the integration of lithological and palaeoecological (foraminifera and diatom) analyses and is discussed. In this study, radiocarbon dating 14C-AMS (Accelerator Mass Spectrometry) was performed using organic materials and bulk of 6 samples. The sample age was calibrated by the OxCal software (Bronk Ramesy and Lee 2013) with a 2-Sigma error range and a reliability coefficient of more than 95%.

3-Results and discussion
The sedimentary succession in undisturbed hand-operated cores and temporary outcrops is described and facies are identified on the basis of lithology, sedimentary structures and macrofossils. Three main sedimentary environments are interpreted from the Holocene sedimentary record of the plain: tidal flat and coastal sabkha, brackish–freshwater marsh and fluvial plain.  This study shows that during the early and middle Holocene, the Lower Khuzestan plain was a low-energy tidal embayment under estuarine conditions. During the initial sea-level rise of the early Holocene, the coastline rapidly transgressed across the shelf, and drowning of a major valley resulted in the development of extended tidal flats. Deceleration of sea-level rise after approximately 5500 cal BP, together with probably more arid conditions, allowed coastal sabkhas to extend widely and to aggrade while the position of the coastline remained relatively stable. Continued deceleration of sea-level rise initiated the progradation of the coastline from ca. 2500 cal BP. The effect of sediment supply by the rivers became more important than the effect of relative sea-level rise. The Karun megafan developed under a descelerating rate of sea-level rise, controlling the avulsive shifting of the river Jarrahi and their loci of sediment input. The development of the Jarahi River megafan has occurred in the study area with a decrease in the rate of sea level rise and stabilization of the river course in the upstream sections of the river, as well as an increase in sediment input from a depth of about 3 to 5 meters depending on the location of the core.

4- Conclusion

As the Jarahi River alluvial fan advances from east to west, environmental changes from coastal and tidal sediments to wetlands and then alluvial sediments appear in the upper part of the cores. The presence of alluvial and wetland sediments in the wetland marginal cores can be affected by changes in the level of the wetland, migration of the Jarahi River channel at the level of the alluvial fan, and human factors and manipulations.

Natural hazards (paleoseismology, landslides, ..)

Geological and Hydrogeological Analysis of Land Subsidence in Hashtgerd Plain and Factors Affecting its Aggravation or Mitigation

Pages 283-296

https://doi.org/10.22034/irqua.2025.2054321.1041

Fatemeh Kalantarian, Morteza Morteza, Mahmoud Navvar Noveiri

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

Quaternary archaeology

Calculation of the geological erosion rate of the Rud-Majan waterfall canyon in Razavi Khorasan based on Corbel's equation

Pages 297-314

https://doi.org/10.22034/irqua.2025.2043510.1032

Fariba Foroughi, Moslem Yazdani, Saman Darvish Bastami

Abstract The canyon of Rud-Mojan waterfall in Torbat-e Heydarieh city is one of the significant Quaternary geological features of the Noth eastern zone of central Iran. This canyon was formed on an area of Lower Cretaceous Rudist limestones, containing Orbitolinid (Barremian-Albian) foraminifera, and from the beginning of the Quaternary. A major deformation and severe erosion have occurred in its limestone beds. The source of its waterfall is related to the quaternary karst water reserves of the northern heights of the Mojan River. In this research, using Corbel's equation (1959) and field studies, the erosion rate of the Mojan waterfall canyon has been calculated. Considering the tectonic and faulting conditions of the region, the creation of this canyon can be considered affected by tectonic-faulting factors and at the same time, water erosion. The results of the calculations indicate that the erosion rate of limestone dissolution in the canyon of Rood Mojan waterfall is about 188.14 mm/thousand years, which shows the relative effectiveness of this model.
Introduction
Dissolution erosion in carbonate rocks and masses depends on several factors. Among these factors are the turbulence or linearity of the system, the flow velocity, the separation of irons from mineral surfaces, the amount of carbonic acid (H2CO3), transport processes, partial pressure of CO2, PH and other factors (Dreybrodt, 1998).
One of the most important studies on karst erosion to date was conducted by the French geographer Corbel (1959). He examined the waters drained by rivers in cold regions and compared them with those in tropical regions in terms of the amount of dissolved calcium carbonate, and concluded that the rate of karst erosion in cold regions was greater than in tropical regions, and this can be justified by the amount of carbon dioxide dissolved in cold and warm water (Corbel, 1959). The main goal of this research is to calculate the karst erosion rate of the Rud-Majan Waterfall Canyon using the Corbel equation.
Material and Method
The canyon (deep valley) of Rud-Majan Waterfall is one of the prominent geological features in the east of the Central Iranian Zone, formed on a Cretaceous (Barremian-Aptian) Rudist limestone area, and especially since the early Quaternary, major deformation and severe erosion have occurred in its limestone bed. Rud-Majan Waterfall is located in Torbat-e Heydarieh province. This waterfall is located in Central Iranian and originates from the Chehel Tan mountain range located 54 km west of Torbat-e Heydarieh city and has an altitude of about 28 meters (Modaresi, 2019). Its geographical coordinates are between latitudes 35°18'50"N to 35°20'55"N and longitudes 58°49'40"E to 58°52'45"E. Among the important tectonic structures, the east-west trending Daruneh fault can be mentioned, and the lithology of the northern part of this fault mainly consists of Paleogene volcanic rocks with inclusions of Nummulitic limestones.
Among the limestones that this waterfall has eroded are those of Lower Cretaceous age. These limestones include Rudist and limestones with benthic foraminifers (Orbitolinides) and are of Barremian and Aptian age and equivalent to the Tirgan Formation in the Kopeh-Dagh Basin and are ridge-forming. These deposits include very thick, strong, rock-forming marly limestone, marl, and calcareous shale, rich in Orbitolinides and Miliolids.
Results
By definition, the incorporation and transport of materials by a fluid agent such as water, ice, and wind are called erosion. Fairbridge (1968) also refers to chemical erosion as opposed to corrosion, and some have considered it to be the same as chemical weathering.
Corbel (1959) proposed an equation to estimate the rate of karst erosion :
(1) X=4ET/100
(2) X=4ETn/100
where X is the erosion rate in millimeters per thousand years (mm/ky) or cubic meters per square kilometer per year, E is the depth of runoff in decimeters (dm), and T is the average concentration of dissolved solids (dissolved calcium carbonate) in water in milligrams per liter (Corbel, 1959) (mg/L).
To use the formula, it should be noted that the density of carbonate rocks should be between 1.5 and 2.9, and for dolomites, the water hardness and temperature must be measured to obtain the dissolution rate through precipitation, and to determine sulfate rocks, the calcium ion content and the hardness of carbonate rocks must be measured. Using the available data and the Corbel equation, the karst erosion rate in the study area was obtained as 188.14 mm/thousand years.
Conclusions
The Rud-Majan Waterfall Canyon in Torbat-e Heydarieh County is one of the most significant geological features of the northeastern part of the Central Iranian Zone, formed on Lower Cretaceous limestones containing Orbitolinid foraminifera (Barremian-Albian). Since the early Quaternary, major deformation and severe erosion have occurred in limestone beds. In this study, using the Corbel equation (1959) the erosion rate of this canyon can be estimated to be equal to 188.14 mm/thousand years. Considering the tectonic and fault conditions of the region, the formation of this canyon can be regarded as being affected by tectonic-fault factors and at the same time, water erosion.
References
Corbel, J., (1959). Erosion en terrain calcaire (vitesse d’érosion et morphologie). Annales de géographie, 68(366), 97-120. https://doi.org/10.3406/geo.1959.16541
Dreybrodt, W., (1998). Limestone dissolution rates in karst environments. Limestone Dissolution Rates in Karst Environments, (16), 167–183.
Fairbridge, R., (1968). Corrosion, etching, Springer Link. Retrieved February 21, 2024, from https://link.springer.com/referenceworkentry/10.1007/3-540-31060-6_69

Quaternary archaeology

Assessing the Relationship between Sediment Production and Site Suitability in Prehistoric Settlement Patterns of the Qazvin Plain Using a Combination of Machine Learning Models, Analytic Hierarchy Process, and Principal Component Analysis

Pages 315-348

https://doi.org/10.22034/irqua.2025.2069959.1055

Soudeh eftekhari, Hassan Fazelinashli

Abstract Introduction
The Qazvin Plain, located on the northern margin of Iran’s Central Plateau, is considered one of the most significant prehistoric settlement centers in the region. Over thousands of years, this landscape has been continuously reshaped by complex geomorphological processes such as erosion, sedimentation, and fluvial dynamics. These processes have not only modified the physical environment but have also influenced the preservation and visibility of archaeological sites. Understanding the relationship between sedimentation and site distribution is therefore critical for reconstructing past environments, interpreting patterns of human settlement, and refining predictive models for future archaeological research. Beyond its theoretical implications, this line of inquiry helps shed light on the decision-making logic of prehistoric communities, their perception of environmental stability, and their long-term strategies for sustaining habitation within dynamic landscapes.
Objectives
This study aims to analyze the relationship between sedimentation intensity and the spatial distribution of prehistoric sites (Neolithic and Chalcolithic) within three sub-basins of the Qazvin Plain—Abharrood, Kharrood, and Hajiarab. The research further seeks to evaluate the relative importance of multiple geomorphological and environmental factors in shaping settlement suitability and to develop an integrated framework that combines machine learning and multi-criteria decision-making techniques for environmental archaeological modeling.
Materials and Methods
The study was conducted in two main phases.
Phase 1 – Sediment Yield Modeling:
Sediment yield maps were reconstructed using the Fournier Index, expressed in tons per square kilometer, to quantify the spatial variability of sedimentation. These initial outputs were subsequently refined using three machine learning algorithms—Multiple Linear Regression (MLR), Random Forest (RF), and Artificial Neural Networks (ANN). For this section ten environmental predictor variables were incorporated, including elevation, slope, clay content, sand content, Topographic Position Index (TPI), Normalized Difference Vegetation Index (NDVI), channel network distance, profile curvature, plan curvature, and lithology. Model performance was assessed using Root Mean Square Error (RMSE) to identify the most accurate algorithm.
Phase 2 – Settlement Suitability Modeling:
A settlement suitability model was developed to identify areas with high potential for prehistoric occupation. Seven key environmental and geomorphological criteria were selected: elevation, slope, aspect, flow accumulation, distance to water sources, distance from faults, and NDVI. These criteria were standardized and weighed using a hybrid approach that combined Analytic Hierarchy Process (AHP) with Principal Component Analysis (PCA). The integration of AHP and PCA ensured that statistical variance structure contributed to the final weighting scheme, thereby reducing subjective bias and improving model robustness. Raster maps were generated in the Python programming environment and subsequently analyzed in ArcGIS Pro, where overlay operations, reclassification, and weighted linear combination were applied to produce the final settlement suitability map.
Results
The machine learning comparison revealed that ANN and RF significantly outperformed MLR, achieving lower RMSE values and higher spatial accuracy. ANN demonstrated superior capability in capturing the non-linear and complex relationships between environmental variables and sediment yield, thereby producing more realistic sedimentation maps.
The suitability analysis showed that the majority of known archaeological sites are located in areas characterized by lower sedimentation rates. Statistical testing confirmed a significant negative correlation between sedimentation intensity and site presence probability. This finding indicates that regions with high sedimentation are less likely to preserve visible archaeological sites, either because such areas were less frequently chosen for habitation or because existing sites have been buried beneath thick sediment layers.
Discussion
The results suggest that prehistoric communities in the Qazvin Plain tended to occupy geomorphologically stable zones with lower sedimentation rates. This pattern likely reflects an experiential understanding of landscape dynamics, even if not formally articulated scientific knowledge. The preference for stable locations may have been shaped by the need for long-term settlement sustainability, reduced risk of flood damage, and better preservation of arable land. It should be noted that the lower number of identified sites in areas with high sediment production may result from their burial beneath sediments rather than deliberate avoidance. Therefore, site burial should be considered when interpreting spatial distribution and settlement patterns.
Furthermore, the use of machine learning techniques, particularly ANN and RF, highlight the potential of artificial intelligence along with Analytic Hierarchy Process to improve environmental reconstruction and predictive modeling in archaeology. These approaches allow researchers to capture complex, non-linear relationships that traditional statistical methods may fail to represent.
Conclusions
This study demonstrates that combining machine learning models with multi-criteria decision-making methods offers a powerful framework for understanding the interplay between environmental processes and human settlement patterns. The integrated approach not only enhances the accuracy of sedimentation modeling but also improves the reliability of archaeological predictive models.
From a practical standpoint, the findings can assist archaeologists in identifying high-probability areas for future excavations, prioritizing regions for survey, and allocating resources more efficiently. Moreover, this research underscores the importance of considering geomorphological stability as a key factor in cultural heritage management. By understanding where sites are most likely to be buried or preserved, heritage managers can design more effective conservation strategies and anticipate potential threats posed by ongoing erosion and sedimentation processes.
On a broader level, the study bridges the gap between archaeology, geomorphology, and data science, offering a replicable methodological template for other regions and time periods. Ultimately, the synergy between AI-driven modeling, PCA, AHP, GIS-based spatial analysis, and multi-criteria evaluation represents a forward-looking approach to environmental archaeology—one that not only reconstructs the past but also informs sustainable management of cultural landscapes for the future.

Geochemical Investigation of Source Rock and Tectonic Setting of the Lut Desert Sand Deposits with Focus on the Rig-e Yalan Region

Pages 349-367

https://doi.org/10.22034/irqua.2025.730079

Roghayeh Delaram, Samad Fotoohi, Hossein Negaresh, Seyed Ali Almodaresi

Abstract Introduction

The Lut Desert, located in southeastern Iran, represents one of the most remarkable hyper-arid regions on Earth, characterized by extreme temperatures, minimal precipitation, and diverse geomorphological features such as kaluts, hammadas, and vast sand seas (Rig-e Yalan). Due to its unique geomorphic and climatic conditions, the Lut Desert provides an exceptional natural laboratory for studying sedimentological and geochemical processes in arid environments. The desert’s surface materials are shaped by the interplay between aeolian, fluvial, and playa processes that operate under intense evaporation and limited weathering.
Despite extensive geomorphological research in the Lut Desert, relatively few studies have focused on the geochemical composition, provenance, and tectonic setting of its surface sediments. Understanding these parameters is crucial for reconstructing source lithologies, sediment transport pathways, and regional tectonic evolution. The present study aims to investigate the mineralogical and geochemical characteristics of surficial sediments in different geomorphic units of the Lut Desert, including kaluts, intermediate hammadas, and the Rig-e Yalan sand sea, to identify their provenance, weathering intensity, and tectonic setting.
 
2.Materials and Methods
Representative sediment samples were collected from multiple geomorphological units across the Lut Desert, covering the kalut area in the west, the intermediate hammada zone, and the extensive sand sea of Rig-e Yalan in the east. Field observations focused on grain size, sorting, rounding, and sediment color, while laboratory analyses determined the mineralogical and geochemical composition.
Mineralogical studies were conducted using optical microscopy and X-ray diffraction (XRD), revealing the dominant minerals present in the sediments. Major and trace element concentrations were measured using X-ray fluorescence (XRF) and Inductively Coupled Plasma (ICP) techniques at certified laboratories. The obtained data were processed statistically and plotted on various geochemical discrimination diagrams to interpret provenance and tectonic environment.
Key geochemical ratios such as Al₂O₃/TiO₂, TiO₂-Zr, Na₂O/K₂O, and SiO₂/Al₂O₃ were used to infer source rock composition and weathering intensity. Provenance and tectonic setting discrimination diagrams, including SiO₂/Al₂O₃ vs. Fe₂O₃+MgO, La/Th vs. Hf, and Ti/Zr vs. La/Sc, were applied to evaluate the dominant lithologic sources and the tectonic environment of sediment derivation.
 

Results and Discussion

Field observations indicated significant textural variation across geomorphic units. Sediments from the kalut areas contained poorly sorted particles with subangular grains and a mixture of quartz, lithic fragments, and carbonate debris, suggesting limited transport and reworking. In contrast, samples from Rig-e Yalan displayed well-sorted, highly rounded quartz grains, reflecting prolonged aeolian transport and mechanical abrasion. These textural differences illustrate the combined effects of aeolian deflation, fluvial reworking, and episodic playa sedimentation on sediment distribution in the Lut Desert.
Mineralogical analysis confirmed that quartz, feldspars, carbonates, and lithic fragments are the dominant detrital components, while heavy minerals such as magnetite, ilmenite, and zircon occur in minor amounts. The abundance of quartz, coupled with depletion in unstable minerals, indicates a high degree of sedimentary maturity, particularly in the aeolian deposits of the Rig-e Yalan. Geochemical analyses revealed that SiO₂, Al₂O₃, Fe₂O₃, and CaO are the major oxides, with SiO₂ content ranging between 62–85 wt%, indicating quartz-rich compositions. Elevated Fe₂O₃ and TiO₂ contents in kalut sediments suggest contributions from volcanic and mafic lithologies. The Al₂O₃/TiO₂ ratios (ranging between 10 and 25) and TiO₂–Zr relationships suggest derivation predominantly from felsic to intermediate igneous rocks such as granites, rhyolites, and volcanic tuffs. The Na₂O/K₂O ratio displays relatively low values, implying advanced chemical weathering and feldspar depletion, consistent with strong mechanical disintegration and limited chemical alteration under hyper-arid conditions. Variations in SiO₂/Al₂O₃ and Fe₂O₃+MgO indicate compositional maturity differences among the three geomorphic zones, with the highest maturity observed in the eastern sand sea.
Provenance discrimination diagrams (e.g., Ti/Zr vs. La/Sc and La/Th vs. Hf) suggest that the majority of samples plot within the field of felsic volcanic and plutonic source rocks, with minor influence from recycled sedimentary materials. The spatial geochemical variability implies that the western and central parts of the Lut Desert receive detritus mainly from igneous and metamorphic rocks of the Kerman magmatic arc, whereas the eastern portions are affected by long-distance aeolian transport and recycling of older alluvial and playa sediments. Tectonic discrimination diagrams (e.g., Fe₂O₃+MgO vs. TiO₂ and Th–Sc–Zr/10) place most samples within the fields of Active Continental Margin (ACM) and Continental Arc Settings (CAS), consistent with the geotectonic framework of Central Iran. This correlation reflects sediment derivation from uplifted continental crust and volcanic arc terranes associated with Neogene to Quaternary magmatism and tectonic reactivation along the Lut block margins.
 

Conclusion

The integrated sedimentological and geochemical data reveal that the surficial deposits of the Lut Desert are products of complex interactions between aeolian, fluvial, and playa processes. The sediments are compositionally immature in the western kalut and hammada regions but become progressively mature toward the eastern Rig-e Yalan due to prolonged aeolian reworking. The dominance of quartz and the depletion of feldspars and mafic minerals indicate advanced mechanical weathering under extreme aridity.
Geochemical ratios and element distributions confirm that the sediments were derived mainly from felsic to intermediate igneous sources (granites and volcanic tuffs) with minor sedimentary recycling. Tectonic setting analysis demonstrates that these deposits originated within an Active Continental Margin environment, consistent with the tectono-magmatic evolution of Central Iran.
Overall, the findings provide new insights into the provenance, weathering, and tectonic controls on sediment composition in one of the driest and most dynamic desert systems of the world. This study contributes valuable baseline data for future research on geomorphological evolution, sediment transport, and paleoenvironmental reconstruction in arid regions of Iran.

Young Alkaline Magmatism in Haraz Road-Polur, Central Alborz: Evidence for the Continuation of a Rift Basin in Alborz.

Pages 368-387

https://doi.org/10.22034/irqua.2025.731449

Ramin Mazandaran, Sayd Jamal sheikhzakariaee, Seyed mojtaba Mortazavi, Mansour Vosoughi Abedini, Abdollah Yazdi

Abstract Introduction:
The Central Alborz has sedimentary rocks from Precambrian to Quaternary. This area is part of the Alborz Mountain range, located in the eastern Central Alborz Zone. It lies between longitudes 50°15’ to 50°77’ and latitudes 35°50’ to 36°15’ North. Alborz’s volcanic activity was strong during the Tertiary period, peaking in the late Eocene and Oligocene. After a calm phase, intense activity resumed in the Pliocene. Eocene and Oligocene eruptions across Alborz, including the Qazvin highlands, Takestan, and areas around Tehran, mainly produced andesite, dacite, and rhyolite. These eruptions also created many ignimbritic and tuffaceous deposits, along with pyroclastic fall deposits and pumice lahar flows (Gholami, 2001).
Sampling Method: During fieldwork, we used a systematic sampling method, collecting 70 samples. We prepared thin sections from these samples for closer examination. To analyze the major, minor, and trace elements, we selected 18 whole-rock samples. These were analyzed using Inductively Coupled Plasma – Mass Spectrometry (ICP-MS) at Kansaran Binalood and Zar Azma companies in Iran.
Discussion: 
After studying the thin sections, we identified four extrusive igneous rock groups: 1) Foliated Basaltic Trachyandesite, 2) Trachyandesite, 3) Olivine Basalt, and 4) Lamprophyres. Diagrams by Lobas et al. (1986) and Middlemost (1994) show that volcanic rock samples from Polur and the Haraz road fit within Trachybasalt, Basalt, and Trachyandesite categories. Based on the classification by Irvine & Baragar (1971), these rocks fall within the alkaline field and near the subalkaline boundary (Tchameni et al., 2006). In the Verma et al. (2006) diagram, the alkali basaltic samples are in the continental rift basalts and OIB (Ocean Island Basalt) fields. The Xu et al. (2015) diagram places these samples in the crustal contamination field, showing magma mixing with crustal components during ascent.
Some sources note that a high Ce/Pb ratio is a feature of mantle-derived ocean island basalts (OIB) (Lustrino, 2005). In the Ce/Pb diagram against Ce for the region's alkaline basalts and primary magma, samples fall within the mantle MORB/OIB range. However, some samples show continental crust characteristics due to crustal contamination and increased lead levels. In the Th/Yb diagram against Ta/Yb, the basaltic samples fit within the OIB range, indicating an asthenospheric origin with some enrichment.
Eskandari's (2016) geodynamic model for Damavand magmatism suggests that the lower crust, lithospheric mantle, and asthenospheric mantle all contribute in different amounts to forming primary magma. To determine the tectonic setting of the studied rocks, we used several diagrams. The samples indicate that these rocks have alkaline traits and formed in an intra-continental rift environment. Unlike the simple fractionation process, LREEs and some LILEs come from alkaline basalts to trachyandesites. Multi-element diagrams show that these elements and P are less in trachyandesites than in basalts. Rare element patterns in these diagrams don’t clearly show a tectonic environment. They show traits of both subduction and OIB environments. A look at some crustal contamination indicators, like elemental ratios, reveals that trachyandesites have more contamination than alkaline olivine basalts. High ratios of Ce/Pb, Nb/U, Ba/Nb, and Th/La, along with low ratios of Sm/La in alkaline olivine basalts, indicate these lavas are influenced more by crustal materials.
Conclusion
Along the Haraz road and near Polur, we find volcanic rocks ranging from alkali olivine basalt to trachyandesite. Instead of a simple differentiation trend, we observe a depletion of LREE (Light Rare Earth Elements) and some LIL (Large Ion Lithophile) elements from alkali basalts to trachyandesites. Multi-element diagrams also show a decrease in these elements and Phosphorus (P) in trachyandesites compared to basalts. The trace element patterns in these diagrams reflect characteristics typical of an OIB environment. Comparisons of crustal contamination indices suggest that trachyandesites have undergone more crustal contamination than alkali olivine basalts. Overall, these rocks show alkaline features and were formed in an intra-continental rift setting.
 

Natural hazards (paleoseismology, landslides, ..)

Landslide in Hossein Abad Kalpoosh village in Semnan province (from occurrence to stabilization)

Pages 388-411

https://doi.org/10.22034/irqua.2025.2068825.1051

saeedmohammad sabouri, Seyed Amirhossein Garakani, ebrahim haghshenas

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

Neotectonics and faults

Tectonic dynamics and Quaternary volcanic eruptions: Quantitative evidence of geodynamic interaction in northwestern Iran and the South Caucasus

Pages 412-429

https://doi.org/10.22034/irqua.2025.2073561.1058

Ateyeh Sanakhan, ali solgi, Ali Sorbi, Mehran Arian

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.


References
Aki, K. and Richards, P.G., 2002. Quantitative seismology. University Science Books.
Ambraseys, N., 2009. Earthquakes in the Mediterranean and Middle East: A Multidisciplinary Study of Seismicity up to 1900. Cambridge University Press, Cambridge.
Ambraseys, N.N. and Melville, C.P., 1982. A History of Persian Earthquakes. Cambridge University Press, Cambridge, 1, 219 pp.
Baftipour, M., Jarahi, H., Polat, G. and Seifilaleh, S., 2022. Damavand Earthquake of 2020 the Mainshock or an Alarm for Disaster for the Capital of Iran. American Journal of Engineering and Applied Sciences, 15(1): 51-58.
Berberian, M., 1994. Natural hazards and the first earthquake catalogue of Iran, 1. International Institute of Earthquake Engineers and Seismology, 603 pp.
Bonali, F., Corazzato, C. and Tibaldi, A., 2012. Elastic stress interaction between faulting and volcanism in the Olacapato–San Antonio de Los Cobres area (Puna plateau, Argentina). Global and planetary change, 90: 104-120.
Davidson, J., Hassanzadeh, J., Berzins, R., Stockli, D.F., Bashukooh, B., Turrin, B. and Pandamouz, A., 2004. The geology of Damavand volcano, Alborz Mountains, northern Iran. GSA Bulletin, 116(1-2): 16-29.
Fedele, L., Ghazi, J.M., Agostini, S., Ronca, S., Innocenzi, F. and Lustrino, M., 2023. Concurrent adakitic and non-adakitic Late Miocene-quaternary magmatism at the Sahand volcano, Urumieh-Dokhtar magmatic arc (NW Iran). Lithos, 458: 107344.
Feizizadeh, B., Kazemi Garajeh, M., Blaschke, T. and Lake, T., 2020. An object based image analysis applied for volcanic and glacial landforms mapping in Sahand Mountain, Iran. Catena, 198: 105073.
Ghalamghash, J., Mousavi, S., Hassanzadeh, J. and Schmitt, A., 2016. Geology, zircon geochronology, and petrogenesis of Sabalan volcano (northwestern Iran). Journal of Volcanology and Geothermal Research, 327: 192-207.
Grosjean, M., Moritz, R., Rezeau, H., Hovakimyan, S., Ulianov, A., Chiaradia, M. and Melkonyan, R., 2022. Arabia-Eurasia convergence and collision control on Cenozoic juvenile K-rich magmatism in the South Armenian block, Lesser Caucasus. Earth-Science Reviews, 226: 103949.
Gudmundsson, A., 2020. Volcanotectonics: Understanding the structure, deformation and dynamics of volcanoes. Cambridge University Press.
Gulen, L., Schweig, E., Williams, R. and K., G., 2011. Active fault database for the Middle East region; Earthquake Model of the Middle East EMME Project. 82.
Hedger, E. and Gottsmann, J., 2022. Investigating stress transfer between the Tuz Gölü fault zone and Hasan Dağ volcano (Turkey). Frontiers in Earth Science, 9: 732696.
Hill, D.P., Pollitz, F. and Newhall, C., 2002. Earthquake–volcano interactions. Physics Today, 55(11): 41-47.
Jarahi, H., 2017. Delineate Location of the Last Earthquake Case Study NW of Iran. American Journal of Geosciences, 17(1): 6.
Karakhanian, A., Djrbashian, R., Trifonov, V., Philip, H., Arakelian, S. and Avagian, A., 2002. Holocene-historical volcanism and active faults as natural risk factors for Armenia and adjacent countries. Journal of Volcanology and Geothermal Research, 113(1-2): 319-344.
Karakhanian, A.S., Trifonov, V.G., Philip, H., Avagyan, A., Hessami, K., Jamali, F., Salih Bayraktutan, M., Bagdassarian, H., Arakelian, S., Davtian, V. and Adilkhanyan, A., 2004. Active faulting and natural hazards in Armenia, eastern Turkey and northwestern Iran. Tectonophysics, 380(3): 189-219.
Karapetian, S., Jrbashian, R. and Mnatsakanian, A.K., 2001. Late collision rhyolitic volcanism in the north-eastern part of the Armenian Highland. Journal of Volcanology and geothermal Research, 112(1-4): 189-220.

Climate change, climate events

"Spatial evaluation of heavy metal contamination in soils and alluvial sediments of urban parks in Shiraz using pollution indices and GIS-based analysis"

Pages 430-446

https://doi.org/10.22034/irqua.2025.2069445.1052

Atefeh Nimroozi

Abstract Introduction Urban green spaces, particularly public parks, play a vital role in enhancing environmental quality and improving public health in rapidly expanding cities. However, these areas are increasingly exposed to contamination from anthropogenic sources, with heavy metal pollution being one of the most concerning threats. Urban soils, especially in parks, can accumulate potentially toxic elements (PTEs) due to vehicular emissions, industrial activities, atmospheric deposition, and inappropriate use of fertilizers and pesticides. Monitoring heavy metal concentrations in park soils is therefore essential to evaluate potential environmental risks and inform urban environmental management strategies. This study focuses on the spatial assessment of heavy metal contamination in soils of selected urban parks using pollution indices and Geographic Information Systems (GIS). Heavy metals such as lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), copper (Cu), zinc (Zn), and nickel (Ni) are selected based on their toxicity, persistence in the environment, and potential health impacts on urban populations. Sampling and Analytical Methods Soil samples were systematically collected from different locations within each urban park to capture spatial variability. The topsoil layer (0–20 cm) was targeted, as it is most susceptible to anthropogenic contamination. Samples were air-dried, sieved, and subjected to acid digestion based on USEPA standard protocols. Heavy metal concentrations were then measured using atomic absorption spectrometry (AAS) or inductively coupled plasma mass spectrometry (ICP-MS), depending on the element and required detection limits. Application of Pollution Indices To assess contamination levels, multiple pollution indices were employed: 1. Geoaccumulation Index (Igeo) – developed by Müller, this index compares current concentrations with background values to determine pollution levels. Values are classified into seven categories, ranging from unpolluted to extremely polluted. 2. Contamination Factor (CF) – this index is the ratio of metal concentration in soil to the background concentration, indicating the degree of contamination. 3. Enrichment Factor (EF) – used to differentiate between anthropogenic and natural sources, calculated using a reference element such as Fe or Al. 4. Pollution Load Index (PLI) – provides a cumulative indication of overall pollution status across multiple metals. 5. Ecological Risk Index (RI) – developed by Hakanson, this index combines toxic response factors with contamination levels to quantify ecological risk posed by each heavy metal. These indices offer a comprehensive view of the contamination status and help prioritize elements of greatest concern. GIS-Based Spatial Analysis GIS tools were applied to interpolate the spatial distribution of heavy metals across the park areas using kriging or inverse distance weighting (IDW) methods. This spatial analysis helps identify pollution hotspots and understand the influence of surrounding urban land use on soil contamination. In addition, land use maps, traffic density data, and proximity to pollution sources (e.g., highways, industrial zones) were integrated to explore potential sources of contamination. Layered visualization through GIS enhances interpretation and supports urban planning decisions. Results and Interpretation The results revealed considerable variations in heavy metal concentrations across different parks, with some areas exceeding international soil quality guidelines, particularly for Pb, Cd, and As. The Igeo values indicated moderate to high pollution levels in parks adjacent to high-traffic roads and industrial areas. CF and EF values confirmed anthropogenic contributions, with significant enrichment for Cu, Zn, and Pb. The ecological risk assessment highlighted Cd as the primary element posing considerable risk, followed by As and Pb. Some park locations fell into the "considerable risk" category according to the RI values, underscoring the need for targeted mitigation measures. Spatial distribution maps generated by GIS clearly identified pollution hotspots and indicated a correlation between metal accumulation and nearby anthropogenic activities. Parks located in city centers or near transportation corridors showed higher contamination levels, emphasizing the importance of buffer zones and soil remediation interventions. Environmental and Public Health Implications Heavy metal accumulation in urban park soils not only degrades soil quality and ecological health but also poses direct and indirect risks to human health. Children are particularly vulnerable due to frequent contact with park soils through play. Chronic exposure to heavy metals can lead to neurological disorders, kidney damage, and developmental delays.   Therefore, understanding spatial patterns and ecological risks associated with heavy metal contamination in urban parks is critical for environmental risk management. The application of pollution indices and GIS supports evidence-based decision-making and enhances public awareness. Recommendations 1. Regular Monitoring: Establish long-term monitoring programs in urban parks, especially in high-risk zones. 2. Remediation Strategies: Use phytoremediation or soil amendments to reduce bioavailability of heavy metals. 3. Urban Planning: Design green spaces with buffer zones and low-exposure zones for children. 4. Public Education: Raise awareness about contamination risks and promote safe park usage practices. 5. Policy Development: Implement regulations to limit urban emissions and manage land use near green spaces. Conclusion This study underscores the significance of combining pollution indices and GIS tools to assess heavy metal contamination in urban park soils. The findings reveal spatially heterogeneous contamination patterns and identify ecological and health risks, particularly in parks located in densely populated or industrialized zones. An integrated approach to monitoring, remediation, and urban design is essential for safeguarding environmental quality and ensuring the safe use of urban green spaces.

Natural hazards (paleoseismology, landslides, ..)

Investigation of hydro-geochemical quality of surface water for drinking water use (Case study: Qalikuh region, Lorestan province, southwest of Iran)

Volume 7, 1, 2, September 2021, Pages 39-57

https://doi.org/10.22034/irqua.2021.702415

Amir Saeed Hosseini, Saeed Hakimi Asyabar, Mozhgan Salvati

Abstract Introduction
Rivers are one of the most important water resources and it is very important to study their water quality. Therefore, in this study, sampling was done from 15 permanent waterway stations of Pirbadush and Gashun of Qolyan River in Lorestan province, which are located in the path of oil shales.
 
Materials and Methods
 Hydro-geochemical parameters were calculated by analyzing the samples in the laboratory. Then compared with drinking water quality assessment standards in the region and Hydro-geochemical diagrams were also drawn.
Discussion and Results: Qolyan River water contains a lot of calcium carbonate and only sample P3 has more magnesium carbonate that it is unsuitable for drinking due to its high calcium content, but it is suitable based on other parameters.
 
Results
According to Schoeller quality classification, Gashun samples are of lower quality than Pirbadush and by the standards, most samples are within the allowable-favorable range and water of G6, G7, P5 stations have lower quality than other stations. According to the WHO table, the water of the Qolyan River is relatively light in terms of TH and total dissolved solids (TDS) and relatively light in terms of Electrical conductivity (Ec). Based on hydro-chemical tests and data analysis and hardness estimation and comparison with the national standard of Iran and the standard of the World Health Organization, the results of water classification of the samples are as follows: According to the World Health Organization's calcium ion (Ca2 +) content, water samples from G7 and P5 stations are impermissible and based on the total hardness of the Iranian national standard, the water samples of stations P1 and P3 are in the favorable level.
According to hydro-geochemical diagrams, the water quality of Pirbadush waterway is better than Gashun. According to the Piper diagram, In Gashun samples, the tendency of the samples towards magnesium and sulfatation is more than the samples of Pirbadush region. According to the Durov diagram, most of the water samples taken from Gashun and Pirbadush waterways are calcium carbonate (Ca-CO3) and calcium bicarbonate (Ca-HCO3). According to Schoeller diagram, the amount of tumble in the samples of Gashun waterway is more than Pirbadush waterway. According to the ion equilibrium diagram, the amplitude of change of anions and cations in Gashun waterway is more than Pirbadush. According to Stiff diagram, the different origins of the samples indicate the existence of several bedrock sources for the samples, and according to the Gibbs diagram, bedrock and weathering and dissolution are the main factors controlling the water chemistry of the region.
By examining the water quality of Qolyan River in Pirbadush and Gashun waterways with any human activity that it is in the path of oil shales, the results were obtained which are:
-The highest amount of cations and carbonate anion (CO32-), is in G7 station and the highest amount of nitrate anion (NO3-), are in G6 and P7 stations.
-The highest water total hardness (TH) is related to stations G7, G6, P5 and the lowest is related to stations P3, P1, G1.
-The highest total dissolved solids (TDS) in water is related to stations G6, G5,  G7 and the lowest amount is related to P1, P4, P3.
- The presence of higher amount of calcium carbonate (Ca-HCO3) in Gashun waterway than Pirbadush indicates a higher degree of solubility of calc than dolomite in this section.
- High sulfate content in Gashun waterway (especially G1 station) can be related with further dissolution of anhydrites in the Gotnia Formation.
-Anion and cation equilibrium also shows that ionic equilibrium is present only at stations G3, G5, P6. However, at stations P1 and P3, there is a high degree of ionic imbalance between anions and cations.
 
Conclusion
 In this area, the type of rock units and even the presence of oil shales have not had a detrimental effect on the quality of drinking water.

Sedimentary environments, paleogeomorphology

Assessment of active tectonics based on geomorphological and morpho-tectonic analysis of the basin (case study: Qeshm Island)

Volume 9, 1,2, September 2023, Pages 213-238

https://doi.org/10.22034/irqua.2023.709905

Adel Rasooli, Mehran Maghsoudi, Aboulghasem Gorabi

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.

Quaternary archaeology

Techno-typological Analysis of Qaleh Kurd Cave Lithic Industries, Aavaj, Qazvin

Volume 8, 3,4, February 2023, Pages 262-288

https://doi.org/10.22034/irqua.2023.705430

Zahra Kamrani, Hamed Vahdati Nasab, Stephanie Bonilauri, Seyyed Milad Hashemi Sarvandi, Mozhgan Jayez, Mohammad Akhavan Kharrazian, Seyyed Iraj Beheshti, Gilles Berillon

Abstract Introduction
Qaleh Kurd cave is located in the village of the same name in the vicinity of Hesar Valiasr village, Avaj city, Qazvin province. This cave is located on the route between Zagros and Iranian Central Plateau and along one of the proposed corridors of scattered human groups in the Iranian Plateau (Vahdati Nasab et al., 2013; Dennell, 2020; Shoaee et al., 2021). The first archaeological study in the cave was conducted in 2013, in which a small surface collection of 35 stone tools on the surface was studied and attributed to the Middle Paleolithic era (Soleimani and Ali Beigi, 2018).
With the initial investigation of the walls of the pits caused by unauthorized excavations and the presence of cultural materials and animal remains in the cave, the first idea about the possibility of exploring this area was formed. The first examination in Qaleh Kurd cave was conducted in 2017 by some of the authors (HVN & GB). Consequently, the joint Iran-France mission under the supervision of (Vahdati Nasab, Berillon and Hashemi) conducted three archaeological field mission in there (2018, 2019, 2022). It is worth mentioning that here we only present data collected during the first two seasons.
Some of the major goals of conducting field missions in Qaleh Kurd are: Investigating the Paleolithic deposits, how the site was formed, comparing lithic industries with other Middle Paleolithic sites of Iran, reconstructing the diet of cave dwellers and trying to obtain human remains. The purpose of this article is to describe the techno-typological aspects of lithic collections recovered from 2018 and 2019 missions and to compare it with the lithic industries of Zagros, and the sites from the Iranian Central Plateau.
Materials and Method
The stratigraphy of the trench 1 wall indicates the existence of two distinct sequences, Holocene and Pleistocene, and the identification of 25 stratigraphic units (1 to 9 related to the Holocene and 10 to 25 related to the Pleistocene). The preliminary results of dating samples taken from 30 cm from the beginning of the Pleistocene layer in Trench 1 indicate an age beyond the range of carbon-14 dating (43,500 years ago). Therefore, in the continuation of the research, the ESR method was used for the dating of cultural materials (especially animal teeth). It is worth mentioning that at the time of writing this article, the above-mentioned chronology is being finalized and the preliminary results indicate an age of more than 300.000 BP for the Pleistocene deposits, which will soon be published in separate research.
The subject of the present research includes the stone artifacts obtained from the exploration of the first and second seasons. In total, 1257 stone artifacts were obtained from excavations in trenches 1 and 3. In this study, the data obtained from Trench 1, the largest explored trench, is presented. The excavation dimensions in trench 1 were 1.2966 square meters in the first season and 6.195 square meters in the second season.
Quantitative characteristics, typological information and technology of tools have been recorded and studied. In a general classification, stone artifacts include tools, debitage, core and core fragments, and debris. According to the stratigraphic information of trench 1, the Pleistocene sequence of Qaleh Kurd is divided into fifteen sedimentological units and five successive archaeological subdivisions. The division of archaeological periods is based on sedimentological studies, changes in the density of stone artifacts and animal remains, and data distribution in depth.
The first period or the late period (QK 1) starts from about -50 to -80 cm (Z) of trench 1 and includes sedimentological units 12 and 11. Unit 11 in the eastern wall of Trench 1 consists of gravelly sand silt with pebbles and flat unlayered gravels with charcoal remains. Unit 12 also includes sandy silt with a number of calcite gravels, a matrix with low compression and more compactness. QK 2, or the middle period, starts from the depth of -80 and continues to the depth of -105. This course is in line with unit 13. This unit in the south wall of Trench 1 has a light brown color and debris pieces and quiet dynamics. Unit 13 on the eastern wall of Trench 1 has sand-silt with many pebbles and flat calcite debris. QK 3 starts from the depth of -105 and continues to the depth of -130. This course includes units 14, 15 and 16. Unit 14 in the south wall of Trench 1 consists of clayey silt with gravel and is brown in color. Unit 15 includes organic silt and unit 16 includes silt (clay). In Unit 16, we see gravel, calcite nodules and ancient soil. On the eastern wall of Trench 1, silt with gravel in unit 14 and silt with organic clay in units 15 and 16 are evident.
The raw materials of Qaleh Kurd stone artifacts are diverse, including limestone rich in silica, jasper, chert group, volcanic stones such as basalt, a limited number of marbles, radiolarite, clay and quartzite. The most used raw materials in all the phases of Qaleh Kurd are siliceous stones rich in lime, so that in the first period 22.5%, in the second period 20.5% and in the third period 32.1% of artifacts are built on limestone.
 
Conclusions
In Qaleh Kurd lithic complex, the cores are very limited and it seems that the initial steps of chipping were done outside the area. A variety of raw materials have been used in this collection, and the three aforementioned Qaleh Kurd periods show different abundances in the use of raw materials. In this area, sidescrapers are the most abundant type of tools, after that we are faced with a significant abundance of points and convergent scrapers. The studies conducted on the quantitative characteristics, typological and technological indicators of the stone artifacts showed that in terms of dimensions and quantitative characteristics, the lithics of the first, second and third periods of the cave demonstrate no difference, but the dimensions of the blades are somewhat different from each other. The comparison of the abundance of raw materials, extractions, platform typologies, and Levallois technique between the periods shows the difference of the third period from other periods to some extent. In this period, we see a high accumulation of lithics compared to other periods, this can be due to the intensity of settlement in this period of the site.
The results of the comparison of Qaleh Kurd stone artifacts with other Middle Paleolithic sites show that Qaleh Kurd cave in the extent of using the Levallois technique, the abundance of scrapers, especially sidescrapers, the abundance of points, especially the Mousterian points, the faint presence of notch/denticulates and, the intensity of retouching and the abundance of flaked base debitages show a closer proximity to the Zagros sites.

Neotectonics and faults

An analysis of environmental evolution in the area of Qalae Bon, Babol city, Mazandaran province

Volume 7, 3,4, March 2022, Pages 340-369

https://doi.org/10.22034/irqua.2022.702439

Mojtaba Safari, Hamid Nazari, Hassan Fazli Neshli, Elaheh Rahimi, Mina Madihi, Hassan Afshari, Narjes Heydari

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...

Neotectonics and faults

Quantitative analysis of the tectonic effect on the longitudinal profile of rivers in the southeast of Ardabil

Volume 9, 3, 4, October 2023, Pages 497-518

https://doi.org/10.22034/irqua.2025.2023612.1024

Nasim Ramezani, Saeid Asiabar, Maryam Dehbozorgi, Reza Nozaem, Hamed Alianpour

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.

Climate change, climate events

Holocene Vegetation and Climate Changes in Iran

Volume 3, Issue 3, Autumn 2017, Pages 205-229

https://doi.org/10.22034/irqua.2017.701911

Ghasem Azizi, Sahar Maleki, Mostafa Karimi, Reza Shahbazi, Homa Rostami

Abstract Vegetation is very sensitive to climate change and is an important factor for identifying the changes of climate and environment. In 12000 to 6000 years ago there was extreme climatic conditions in the southwest Asia with hotter and longer summers than the current conditions. As a result of such climatic conditions, many shallow lakes and seasonal rivers have been disappeared and vegetation altered. Plants that were more adapted to environmental conditions and dry seasons like annual plants includes (peas, lentils, wheat ) by the  changes in legume and shape of the grain, completed their annual life cycle. Studies have shown that the climate has changed between cold and dry conditions during glacial and hot and humid periods in interglacial in north and west of Iran. The lake sediments and paleo sol layers in loess deposits indicate there was an increase humidity during period between the last interglacial and pre end glacial period (Kehl, 2009). The Palynological results of paleo ecological sites in west of Iran have shown that there were steppes of Artemisia and chenopodiaceaes in glacial periods that represent cold and dry climate in this region. About 6500 years ago, Zagros oak forests have replaced by pistachio-oak vegetation. Studies in parts of Iran such as Zaribar Lake, Urmia Lake, Mirabad Lake and comparison with the Van Lake in Turkey showed that they have almost the same vegetation changes. In all of these studies, the end of the Yongerdryas and the beginning of the Holocene by a sudden increasing in chenopodiaceae vegetation (which represents cold and dry weather) and gramineaes ( which represents warm and dry weather) are characterized (Davoodi et al,2014). Generally, the global climate cycles and events in different parts of the Iran are rarely studied and our understanding of paleo climate and paleo ecological conditions is very insignificant. Pollen data from lakes or tree rings data have the potential for identify the paleoecology conditions in Iran.
Result and Discussion:
Climate and vegetation changes in Iran in Holocene:
Palynological studies in Komishan wetland (located on the southeastern part of Caspian Sea) has provided significant results about vegetation changes and sea level fluctuations. Delay in forest growth at beginning of the Holocene, which is in areas of eastern Turkey, there was also on the plateau of Iran and the south of the Caspian sea and in the northeastern slopes of the Alborz mountain (Gomishan). Pollynological studies and radiocarbon dating in Neur lake showed about 12800 years ago, in the late glacial ratio of trees pollens has been negligible,in the transition to the early Holocene pollens of trees and shrub vegetation such as Ephedra gradually increased. During Younger Deryas in Neur,the grasslands replaced with trees.In early Holocene at 9800 years ago Artemisia increased in Neur because it seems that there was a more milder phase in the north of Iran.  An increase in Oak and herbaceous palnts pollens such as artemisia showed that between 8000 and 9000 years ago there was wet phase in the  Neur basin. The presence of  high  amounts Alnus  pollen in the north of Iran  has shown that there were humid climate in the northern parts of Iran at 3000 years ago. Evidences suggests that highest levels of Caspian sea occurred between 1900 and 2100 years ago.

vegetation and climate in Holocene in the west of Iran

In the west of Iran during the 40000 to 20000 years ago, there was scattered vegetation (shrubs and trees). In late Pleistocene (22000 to 14000 years ago) there was arid and semi arid steppes in this region. In interglacial period in Holocene (10000-6000 years ago) precipitation increased Gramineae replaced with chenopodiaceae and Almond and Pistacia atlantica grew up such a change in vegetation indicates an increase in precipitation.In the Zagros mountain 7000 years ago Pistachio trees have existed which represent dry climate in early Holocene in this area. In mid Holocene moisture increased and vegetation was changed to Oak-Pistachio forests.In the early Holocene in western regions of Iran winter rainfall has increased and have been dry conditions in summers,In 6000 years ago in mid Holocene there was warm and humid climate in this region and Oak forests expanded. In the west of Iran, Almond and pistachio forests were more than Oaks, it indicated that humidity in spring and summer was more than other seasons in early Holocene. 
In the Last glacial  Period The Ephedraceae shrub steppes has been developed(Djamali et ak,2008).In middle of the last glacial period the water level of Lake Urmia increased, In transition between last glacial to Holocene in the west of Iran, dominant plants were ephedraceae,pistachio,Oak, Juniperus excels and Betula alba.Untill 9000 years ago dominant plants in Urmia basin was Artemisia steppes,In this basin, forests has been developed between 8000-9000 years ago.The results of Studies showed that Pollens in the west of Iran decreased in 2500 to 1500 years ago and replaced with Artemisia pollens (Talebi et al,2015). In Late Holocene Pollens such as Oak pollens has icreased (1600-1200 years ago) and there was a humid climate in the west of Iran.Also the level of Urmia lake was higher than present and the water salinity was lower.Presence of Reilla spores and low magnetic sensivity and calcium carbonate values confirmed this fact. in 1200 to 900 years ago water level in  Urmia lake decreased,  on the edges of lake ,Halophytes increased. The semi desert steppe developed in area. Pollen of Artemisia and Chenopodiaceae, Senecio vulgaris, chamomile and  Acantholimon has increased that indicate the dry and cold climate. At 650 to 450 years ago lavel of lake increased. Pollens of Juniperus represents a cold and dry climate in this region.
In the late Pleistocene and Younger Deryas period, the south Zagros had a Cold climate with steppe vegetation(Davoodi et al,2014). Davoodi et al(2014) concluded that bigining of Holocene in Parishan lake was about 10200 years ago and lasted to 8170 years ago. In this period Artemisia and Chenopodiaceae have decreased and Geraminea have increased. So we can concluded that the humidity in spring and Summer have increased but it was not enough to grow Oak trees, of course Almond and Pistachio trees grew well. Precipitation required for the growth of almond and pistachio forests is about 300 mm but for Oak forest it is 500 mm.Evidences indicated that climate in early Holocene in the southern Zagros Mountains was dry and hot. In 8170 to 7570 years ago Gramineae vegetation decreased    around Parishan Lake and cold resistant plants such as Cousinia, Umbelliferae and Cichorioideae plants has increased (والتر،1971). In this period dry climate has dominated and summer precipitation has decreased. In 7570 to 5600 yaers ago Oak forests expanded also Almond trees and Asparagus trees increased around the southern Zagros.in this period humid climate has dominated.  In western and southern parts of Iran, In 5600 to 2700 years ago Climate was warm and humid.
North west-West of Iran
The vegetation and climate of southern and southeast of Iran  in Holocene:
Distribution of grain size,petrographic characteristics and sedimentary cores chemical measurements show that:

There was a  full of water lake in Sistan basin, in the late glacial to Early Holocene. MLW(Mid Latitude Westerly currents) and ISM (Indian Monsoons) precipitations has fed the area.
In Early Holocene to Mid Holocene  ITCZ  moved to  the south so ISM weakened, as a result, dry periods started in Sistan basin. High pressure gradient between Sistan depression and Hindu Kush Mountains caused severe and persistent dust storms.
In mid Holocene to late Holocene hydroclimate regime in Sistan basin has controlled by MLW precipitations. The frequent fluctuations iin the water level of Lake Hamoon represent the unsustainable climate  in early Holocene to mid Holocene.
There are not enough information about pollens in the south-southeast of Iran and we can only reconstruct vegetation 1900 years ago. Results show that 910 years ago in this region plains turned into deserts.
Climatic anomalies in Medieval in 1145-910 years ago xerophytes grew in south and southeast of Iran. Impagidinium paradoxum in gulf of Oman Indicated the absence of ocean water drainage.

 By using pollen data and sedimental cores Miller et al (2016) reconstructed vegetation in south of Iran and reconstructed vegetation areas:
The overall dominance of Poaceae, at the expense of Amaranthaceae and Asteraceae and the decrease in clay abundance throughout the LIA suggests a shift from desert to grassland vegetation, implying wetter conditions during the LIA in S Iran. Modern ecoregions within close proximity to the coring locality where grass is a dominant component of the vegetation composition include the Zagros Mountain Forest Steppe and the Baluchistan Xeric Woodlands, where annual precipitation exceeds more than 150 mm per year, Additionally, the abundance of I. paradoxum and Dubridinium sp. is low suggesting an increased amount of freshwater discharge into the ocean. The high abundance of S. ramosus a species particularly observed where the upper water salinity conditions are reduced permanently, again suggests more freshwater discharge into the ocean near the coring vicinity. The low pollen to dinocyst (PD) ratio values during the LIA indicates more marine organic flux, likely due to increased nutrient supply promoting an increase in dinocyst populations. A decrease in Betula and a slight increase in Amaranthaceae abundance are evidenced during the last c. 100 years, which may
 
Conclusion:
Climatological and vegetative evidences suggests that cold periods in Iran have been accompanied with increase in air aridity. Probably in cold and dry periods Siberian anticyclone was strengthened and led to weakening and southward shift of monsoons. Perhaps at that time cyclones of westerlies were also weakened. In northern Iran prevailing winds were from north or northeast, have originated from central Asian deserts. Evidence of these winds are Quraqom desert sand dunes and the spatial distribution of loess deposition in Kopet Dag and north of Iran. During the glacial periods direction of prevailing winds have been northwest to northeast for tropical currents (Kehl, 2009). In the Quaternary period in Iran climate has changed several times, glacial periods has dry and cold climate than now, also many of studies concentrates on west and north parts of Iran and there is no enough data and information for the east and central parts

Climate change, climate events

Review of sclerochronological studies of seashells to regenerate climatic conditions: Growth pattern and measurement of stable oxygen isotope ratios

Volume 7, 3,4, March 2022, Pages 427-459

https://doi.org/10.22034/irqua.2022.702443

Alireza Kochzaei, Salar Yazandan Bakhsh, Mohsen Mohammadi Achacheloi

Abstract Gastropoda and Bivalvia as Mollusks are invertebrates which have a layer made of calcium carbonate for protecting their soft bodies known as shell. One layer is added to the shell in each stage of growth, like annual rings in a tree. These circles are formed dark or light as well as strong and weak layers. Researchers are trying to find out reasons and conditions of improvement and acceleration or stopple of growth. This field of science known as sclerochronology, can be used to analyze the growth bands of shells. Materials for producing the shell have been absorbed from environment. Therefore, information of environmental and growth conditions have been saved on these layers.The information is resulted from the data in the shells through sclerochronological studies. Therefore, sclerochronological methods are one of the best scientific methods with high accuracy that allows the study of animal growth conditions as well as environmental and climatic changes. These studies as one of sclerochronological methods are known as sclerochemistry. In the last few decades, sclerochronological methods have been considered by researchers in other fields, including paleontologists and archaeologists, in addition to biologists. Contrary to its importance and precision for study of environmental conditions and climatic variation in the past, it is unknown to many researchers. On the other hand, even after the 1940s and the invention of the term sclerochronology, many researchers who had previously used this method to evaluate their hypotheses, especially in oceanography and marine biology, to determine age, growth pattern, and aquatic conditions, have not used the term sclerochronology in their reports. This is the most important reason why sclerochronology remains unknown among researchers. In addition, in sclerochronology we encounter different species of organisms. It makes challenging differences in the study process of growth pattern or sampling for isotopic analysis and access to environmental information. Also, some Species that can be examined are not suitable for answering all the questions. Although, this capability may be lost in some approved species over time and therefore they are no longer suitable for analysis.There are even species that only certain parts of them can be examined. Some cases have made it difficult for new researchers to study related methods, and have limited their studies. This article tries to characterize an important part of these problems by reviewing the background and literature of sclerochronology and sclerochemical methods for reconstruction climatic conditions through library studies.
 

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