مجله پژوهش های دانش زمین
پیاپی 50 (تابستان 1401)

The North-Caspian Sea Pattern (NCP) is one of the atmospheric phenomena that originates from the pressure fluctuation at the 500 hectopascals level between the North Sea and the Caspian Sea. For the North-Caspian Sea Pattern, a numerical index has been defined, which is calculated based on the geopotential height difference of 500 hectopascals between the North Sea and the Caspian Sea. After the numerical calculation of this index, the output number is positive or negative, and the output of the positive number indicates the negative phase and the output of the negative number indicates the positive phase of this index.

To investigate the relationship between the precipitations of Ardabil province with the North-Caspian Sea Pattern, first the average precipitation, temperature and relative humidity of Ardabil, Parsabad, Khalkhal and Meshgin-Shahr stations during 1987-2015 was prepared from the IRI Meteorological Organization.Then, the data of the North-Caspian Sea Pattern for the period of 1987 to 2005 were prepared and used from the climate research system of East Anglia University. In order to calculate the mentioned index until 2015, statistical equations were used and the numerical amount of NCP index was prepared for the years 1987 to 2015.Then the monthly, seasonal and annual relationship of the North-Caspian sea pattern with the parameters of precipitation, temperature and relative humidity of Iran during a period of 29 years (1987-2015) was investigated with Pearson correlation at 95 and 99% level. In order to model the relationship between precipitation and the NCP model, the forward perceptron artificial neural network model was used.

The results showed that the correlation between monthly, seasonal and annual precipitation in Ardabil with the NCP index is not significant, and relative humidity has no significant relationship with the NCP index, but the temperature in February and July had a significant relationship with the NCP index at the 95% level.The results also showed that the relationship between precipitation and NCP index in Khalkhal is more than Ardabil, which was significant in November and December as well as summer and autumn seasons and the annual average of their relationship was significant at the 95 and 99% level. In November and December (autumn season), the correlation coefficient of precipitation and NCP index was positive, which shows that the amount of precipitation increases as the NCP index becomes positive. The correlation between the NCP index and the precipitation of Mashgin-shahr in January and December was significant and positive at the 95% level. The highest correlation between precipitation and NCP index was observed in Pars-Abad, especially in autumn, and at the 99% level, their correlation was significant and positive; this means that with the positive NCP index, the amount of autumn precipitation in the Moghan Plain will also increase. In order to fit the best artificial neural network model to the data, a regression line was used, and in this model, the R coefficient was 0.98 for the test data, 0.98 for the validation, and as overall, for the mentioned neural network model, its coefficient was equal to 0.98%, which indicates the appropriate fit of the model in predicting the amount of autumn precipitation in Pars Abad.

Moghan Plain, which is located in a flat area, and Sablan Mountains and high altitudes do not have an effect on its climate, are the only Tele-connection patterns that determine its precipitation regime, and this is the reason why the relationship between autumn rains is positive and significant with the NCP index. The positive phase of the North-Caspian sea pattern has been associated with the high Mediterranean trough, so that the studied area is located in front of the trough and the transfer of moisture from the Mediterranean Sea, the Atlantic Ocean and the Black Sea has caused autumn rains in Parsabad. Therefore, in spite of the influence of ENSO and North Atlantic Oscillation patterns on the precipitation of Ardabil province, the North-Caspian Sea pattern also plays an important role in its autumn precipitation, especially in the Moghan plain.

Coastal areas are constantly changing physically and ecologically, depending on natural and human factors. The natural causes of coastline changes are assessed in three ways: short-term changes including the effects of up and down currents, long-term changes including climate change, periodic storms and waves, and accidental changes including sudden natural events. These changes affect the coastline and coastal areas and consequently have a negative impact on human life, human activities and maritime communications. Thus, monitoring the coastal area is important for sustainable development and environmental protection. In this regard, to monitor the coastal area, extracting the coastline at different times is essential. The shoreline is one of the most important linear features on the earth's surface that shows the dynamic nature. The progressive of Caspian Sea water during the years 1978 to 1996, which led to a rise in sea level of more than 2 meters, caused great and serious damage to various land uses (including industrial, official, commercial, residential, agricultural land uses and natural resources) and had a special effect on the coats biological resources and ecosystems. On the other hand, in recent year, the water level of Caspian Sea had decreased and it is regressing. The gradual decrease of Caspian Sea level can change the coastline in some parts of the coastal areas, especially in Golestan province and endanger various species of aquatic organisms and plants, and maritime transport industry as well as water quality. Due to the sensitivity and fragility of the coasts against erosion and pollution, the coast management needs an efficient and integrated management system to enable sustainable development in such areas.

Because the dynamic nature, Noor Township coastal area is exposed to erosion and permanent variability due to river, wind, tectonic, wave and tidal processes. The sea water progressive and regressive in study area causes the destruction of coastal facilities and tourism places. Monitoring the trend of shoreline changes and analyzing the extent of its spatial changes in the urban area of Nour and Royan was done based on long-term statistical data of sea level fluctuations (1840 to 2019) in the tide gauge stations of Bandar Anzali and Nowshahr and corresponding satellite images. According to the shoreline extraction selected times in this study, the satellite images of Landsat MSS 1977, Landsat TM 1995 and Sentinel-2 2019 were used to detection the lowest and highest water level shorelines.

The effect of Caspian Sea water level fluctuation during 1977 to 2019 is well reflected in the changing location of Nour and Royan shorelines. The shoreline of 1977, corresponding to the lowest recorded water level, is in a regressive position compared to the later periods shorelines and current conditions. After mentioned year and with the rising sea level, the position of the shoreline has progressed to land, which in 1995 reached its maximum progress. Investigation of the amount of submerged coastal lands in 14 km of the Nour and Royan coastal strip due to the rising Caspian Sea water level illustrates that 214 hectares of these lands have been submerged. After this water rising and coastal lands erosion, from 1955 until now (except for the period of 2001-2006) Caspian Sea water level has been rising. The water level falling has affected the 2019 shoreline location (as an indicator for the last three decades’ lowest sea level) and caused its regressive from the land. Following the shoreline progressive in the same 14 km coastline strip of Nour and Royan, 65.7 hectares have been added to the coastal land area (land reclamation).

According to the latest water level recorded from Caspian Sea level, the sea level has reached its lowest amount in November 2019 during 1976 to 2019 which is equal to -27.31 m. Investigation of long-term Caspian Sea water level fluctuation during 1992-2019 signed that the sea level has dropped at a rate of 12.5 cm per year, which reached from -25.78 m in October 1972 to -27.31 m in November 2019; this shows a drop of 1.44 meters during these years. Generally, changes in Caspian Sea water level occur rapidly and dramatically which is also confirmed by morphological and sedimentological evidence has taken place in this sea.

Due to the interaction of effective factors in soil formation, changes in soil properties from one place to another and even for one type of soil will be obvious. Iran is one of the countries that has many problems in terms of soil erosion, so that every year millions of tons of rich and fertile soil is eroded from its original location due to mismanagement and unprincipled and becomes inaccessible. Continuation of this trend in recent years has led to the creation of acute environmental problems that should be adopted principled and logical solutions to not intensify and continue this trend.

Nomehrud watershed is limited to Noor city from the north and the Caspian Sea from the east to Vazrud watershed from the west to Noorrud watershed and from the south to Haraz watershed. Its area is about 50 square kilometers. The study area is located between the northern latitudes approximately 4014000 to 4027100 and the eastern longitudes approximately 590300 to 597000 (in the utm system). The average annual rainfall is 613 mm. At first, the whole area was divided into one kilometer square networks (1000 meters * 1000 meters) and within each network, according to the conditions of access to different parts of the region and homogeneity in other characteristics (topography, lithology, land use and soil science) two Three soil samples were taken randomly from a depth of 0 to 30 cm. Soil structure was determined directly in the desert. Parameters, percentage of coarse sand (by sieving method), silt + very sandy (by sieving method), organic matter (by walkie-block method), soil structure (in the desert) and soil permeability (using the relationship between soil texture and group Hydrological) was determined and finally the amount of soil erodibility factor was obtained for each sampling site. Finally, the soil erodibility factor was zoned using some interpolation methods.

Due to the existence of land types in the control area, we have a wide range between the minimum and maximum values ​​of the studied parameters and are involved in the soil erodibility factor. The soil structure in the area is mainly spongy grains. Soil permeability is often in the middle to low category, the amount of organic matter between 0.3 to 5.4, silt in the area 4 to 62%, clay 2 to 51%, sand 14 to 72% and erosion factor values ​​between Is set to 0.05 to 0.6. Gaussian model was selected from the fitted models. Considering the accreditation accuracy indicators, it was found that the kriging method has a higher accuracy than other methods. According to the zoning map, soil erodibility factor shows that except for the central parts of the region, which have dense and semi-dense forest lands, other parts of the region are more sensitive to soil erosion, which is mainly due to the reduction. Soil permeability, higher amounts of silt, lower amounts of clay and sand and the presence of formations more susceptible to erosion, etc., which is accompanied by the effect of destructive factors such as overgrazing in pastures (village and upstream lands), destruction of forest areas (Thin) due to the entry and grazing of livestock in these areas and also the unprincipled use of these lands for recreational activities and wood smuggling on the one hand and lack of access to barren and mountainous forest areas on the other(central areas)Be.

Considering the conditions and situation of degradation in the areas of natural resources of the country, estimating and determining the soil erodibility factor and subsequently using it in different models of soil erosion is an important and necessary matter. In general, it can be said that among the various interpolation methods, the kriging method has a special place. According to some researchers, this method works as the best method of interpolation and estimation in non-statistical points in homogeneous regions. This method requires prior calculation and determination of the spatial correlation of field data, which can be done by drawing a toxic experimental variogram and selecting an appropriate mathematical model that can fit its points. One of the advantages of production plans is the quantification of the obtained results, which leads to the ability to reproduce and update the obtained information.

Autumn and winter rains play an important role in Iran's agricultural and livestock economy, as well as feeding underground water tables, especially in the western and southwestern regions of Iran. The continuous reduction of underground water reserves in Iran increases the importance of atmospheric precipitation especially during autumn and winter seasons. This importance is affected by the centrality of agriculture in Iran, as well as the supply of drinking water in small and large cities.
This sensitivity is more in the southern half of Iran and especially in the southwest, which has rivers full of water and it, is a region full of large dams.

In this research, the mechanism of rainfall in the two seasons of autumn and winter in southwestern Iran was investigated and compared. Then, the synoptic conditions of the longest and most intense rainfalls that occurred during the selected data period in the research area were identified. In this research, a rainy day was defined as a day when the weather station received at least half a millimeter of rain. Also, the duration of rainfall at each station was defined as the number of consecutive days of rainfall at that station. In first step, daily rainfall data were collected from 8 weather stations in the 30-year period (1987-2016) in southwest Iran. During the second step, separation of rainfalls according their duration using programming in MATLAB environment; it made it possible to select 40 precipitation samples. During the last step, synoptic patterns were designed from daily weather maps, including moisture flux, atmospheric height, and the position of jet-stream cores.

In this research, the analysis of patterns showed the following results 1) Sources of continuous and widespread rains in the autumn season, warm waters around Iran include the Red Sea, Gulf of Aden, Arabian Sea, Persian Gulf and Oman Sea. 2) The origin of the wet currents of these rains is from the central regions of tropical Africa. 3) During the winter season, these resources are generally limited to the Red Sea and the Gulf of Aden. 4)  Also, the analysis of the position patterns of negative omega cores at the level of 500 hPa indicates the conditions of inflammation and severe thermal gradient in the atmospheric column over the southwestern lands of Iran during the autumn season compared to the winter.

Based on the designed patterns, the western troughs in the eastern Mediterranean deepen during the winter season compared to other seasons and they provide the following conditions for rainfall in southwest Iran: 1) The path of precipitation systems also reaches the southwest of Iran. 2) Stronger cores are formed from jet-stream in the southwest of Iran. 3) More water areas such as the Mediterranean Sea, the Red Sea, the Gulf of Aden and the Arabian Sea contribute to the provision of rainfall moisture.

Introduction and structure:

Today, urbanization has local and global environmental consequences, this is reflected in the light of good management and in the light of looking at human dignity. Researchers have two main interpretations of this concept. First, the analysis begins with the state-centered aspects, and second with the social aspects, which the second approach implies changes in the existing power relations and therefore in the position of the state in the decision-making process. This evolution in the field of management led to the introduction of a green management approach. The benefits of this management can be considered in three parts: environmental benefits, positive economic effects and social aspect.Achieving green government and green management depends on institutional bedrock. Such an issue requires theoretical cooperation on how the green government is formed. The Green City Index is a measure that compares cities based on eight dimensions of sustainable development. The performance reports of these green cities are submitted annually to the World Bank as well as to international organizations.

This research has been conducted at the neighborhood level to study the indicators of urban green management and its effectiveness in order to answer the two questions of study and analysis.The first is the status of green management indicators and the second is the indicators affecting green management in Tajrish neighborhood The conceptual model is considered using community-based thinking and green management approach with global indicators and also using variables such as freedom, civil institutions, rule of law and the creation of justice and equal opportunities. Due to the nature of the research, the methods of data collection are library and field. The indicators were developed and then the relationship between the indicators of urban green management from the perspective of neighborhood residents was analyzed. SPSS and PLS software were used to analyze the data.

The results of the analysis of the current situation of urban management in Tajrish neighborhood based on green management indicators, indicate the unfavorable situation of urban management. Findings indicate that the highest average is related to the economic index (3.10). In the meantime, it seems that this space can improve its performance according to the existing potentials and indicators including green jobs, green investment and green taxes. The Green Infrastructure Index with its items shows that it has an average economic function with the region and has more income and also has a good infrastructure compared to other indicators with an average (2.92) but is lower than the average. Indicators for measuring the green community (2.77) Due to its age, the existence of Imamzadeh Saleh and the reliance on the market of social participation and cohesion, it has near-average conditions., Green Justice (2.10), Green Energy (1.82) are in the next ranks, respectively. Which is not suitable, especially the green energy index and its main is the lack of education and information. Due to the strategic location in this neighborhood, attention to environmental issues and the need to reform the structure of management and planning, as well as policy-making for the development of the green city is reminded. Therefore, considering the average indicators of green management, it can be said that urban management is of low quality due to the situation and potentials in Tajrish neighborhood. The results also show that the green community index explains green infrastructure and green community more than other green management indicators. In terms of infrastructure and green economy, due to the favorable situation of the residents of the neighborhood, green management can be explained by planning and reforming the structure of urban management.

Think of urban management as a system The implementation of green management in this system requires a dissent, democracy and the rule of law under the supervision of civic institutions. Transformation requires reforming the urban management structure from the current situation with a green approach to sustainable development. The current situation of urban management in Tajrish neighborhood has not been implemented due to the needs of its residents, the environmental conditions in this neighborhood and the residents' polls prove this claim.

The studied section is located in the eastern margin of Lut block, 38 kilometers south of Birjand (Iran) in the east of Ali Haji village. It is situated within the geological sheet map of Birjand (Ohanian and Tatevosian, 1978).The present study aimed to identify foraminifera assemblage in the measured section and present a biostratigraphic scheme. In addition, we evaluated the correlation of the studied section with other previously studied sections in the vicinity of Birjand.

This study was conducted on 10 rock samples and 29 soft shale and marl samples. The thin sections were photographed. After washing and separating the foraminifera from the sediments, imaging was performed using Scanning Electron Microscope (SEM).

The section starts with a basal conglomerate, which is overly on the ophiolites (peridotite) unconformably. This conglomerate is composed of peridotite fragments, which are gradually converted into sandstone and calcareous sandstone. The succession continues with thick, cream-colored foraminifera limestone. The upper portion of the lower sequence and the middle segment mostly contain light-to-dark gray marl with thin layers of shale (colored gray-to-olive). The upper portion could be divided into two parts; the lower part contains most of the gray shale and sandstone with some trace fossils, and the upper parts mostly contain a grayish-green shale, which is formed between the layers of marl and gradually disappears, causing a reddish-brown shale to appear on top of the sequence. In addition, the biostratigraphic studies in Ali Haji section led to the identification of twenty genera and thirty species of benthic, as well as five genera and nine species of planktonic foraminifera. As a result, five biozones were introduced, including ; 1- Alveolina assemblage zone 2- Morozovella aragonensis interval zone 3- Turborotalia cf. possagnoensis taxon range zone4- Subbotina bolivariana taxon range zone 5- Uvigerina jacksonensis assemblage zone. Based on the introduced zones, the age of the studied section is suggested a late Paleocene to late Eocene. Furthermore, the comparison of the Ali Haji section in the south of Birjand showed correlations with the Ching Dar and Grong sections, the Dahan Rud section, and the Friznook section in the north of Birjand. The thickness of the detrital units at the base of the section during the Paleocene was observed to be more significant in the north of Birjand compared to the south, which could be attributed to the further subsidence of the basin due to the activity of synsedimentary faults, earlier transgression in the north, or higher altitudes in the south (paleo-high) in Paleocene.The limestone units in the southern part will be transformed into marl and marly limestone units. In the northern part, the thickness of limestone was considered significant in Ching Dar and Dahan Rud sections.In the Dahan Rud section, sandstone and conglomerate intercalations were thicker compared to the other sections. Although limestone and marl units were identified in the Friznook section, the detrital facies was thoroughly spread possibly due to flysch deposits with fossil trace diversity.

According to the results, the Ali Haji section in the south of Birjand with a thickness of 560 meters had conglomerates, limestone, nummulitic limestone, marly limestone, marl, shale, and sandy limestone. Due to the distribution and identification of foraminifera in the Ali Haji section, a late Paleocene to the late Eocene age is speculated. Given the disconformity boundary of ophiolites and Paleocene deposits, it could be concluded that the ophiolite placement occurred before the Late Paleocene.

The studied area, which is a part of the central Iran zone and the magmatic belt of Urmia-Dokhtar zone, is located in Isfahan province, Kashan district. Due to the volcanic and plutonic evolutions of Urmia-Dokhtar zone, various types of iron mineralization can be found in this zone in the form of hydrothermal, skarn and volcanic. Since the ASTER and EO-1 sensors are powerful in the short-wave infrared (SWIR) and visible-near-infrared (VNIR) spectrum bands, respectively, therefore, in this research, the combination of these two bands from these two different sensors was used to increase the precision and accuracy of iron prospecting through remote sensing in the Kashan district.

The remote sensing process of the studied region comprises two stages. The first stage is pre-processing and data preparation before entering the processing stage. The second step is determining the best bands of ASTER and EO-1 ALI sensors and applying processing techniques containing false color composite (FCC), banding ratio (BR), Crosta selection method or directed principal component analysis (DPCA), supervised classification through spectral angle mapper (SAM) method and classification by the land surface temperature (LST) method which finally alteration-zoning map associated with iron mineralization in the studied region was produced.Aeromagnetic data was acquired in an area of approximately 852.5 km2 in 754 stations with flight lines interspacing of 7.5 km on the alteration zones related to iron mineralization obtained by remote sensing method. Geosoft Oasis montaj software was employed for processing operation and qualitative interpretation of magnetic data via applying various corrections and filters including reduce to pole, upward continuation up to the variety of elevations, low-pass filter, derivative filters containing total horizontal derivative and analytical signal. To simulate and model the magnetic data, the studied area was divided into three-dimensional blocks with dimensions of 125*250*250 meters. At the end, to investigate the trend of magnetic anomalies observed on the surface, determination of approximate shape of the deposit and estimation of its depth, 3-D inverse modeling of the data was carried out using Lee and Oldenberg algorithm by UBC Mag3D 4.0 software.

In this study, to identify phyllic alteration zones, bands 4, 6, and 7, argillic alteration zones, bands 4, 5, and 7, and propylitic alteration zones, bands 7, 8, and 9 from ASTER sensor was used as input to the component analysis method. The spectral angle mapping algorithm was applied with the data of both ASTER and EO-1 sensors which according to the obtained results, the ASTER sensor was better than the EO-1 to detect iron-related alterations. To calculate LST, radiometric and atmospheric temperature corrections were made on the band 10 ETM8 sensor whereas geometric and radiometric corrections were made on multispectral bands. The magnetometric studies of the region showed that the greatest changes in the intensity of the magnetic field are in the center of the study area and the continuation of these changes is towards the southeast of the area.

Based on the results of the recognition and prospecting phases by remote sensing method and the possibility of iron oxide in the area using airborne magnetometry, making the necessary corrections and applying various processes on the data, the anomaly zones of the area were identified. As a result of the three-dimensional modeling and inversion process of the magnetic data, two large masses located in the center and southeast of the region were identified. The results of the research through integrating two fast and relatively inexpensive methods of remote sensing and airborne magnetometry with 3-D inverse modeling of magnetic data, reveal that Kashan district has a high potential from viewpoint of iron ore-bearing.

K-feldsapr, muscovite, and biotite exist in barren granites, fertile granites and rare-element pegmatites. These minerals can be host of Rb, Sr, Ba, Li, Cs, F, Sn, Zn, Sc, Nb, and Ta. Abnormalcy in the content of these elements is a good exploration tool for discriminating barren and fertile granites. Also, K/Rb ratio and Rb, Li, Cs, F, Sn, and Zn values in mentioned minerals are useful indicators for determining the degree of granitic magma fractionation. These minerals are used in classifying pegmatites and studying their genesis. In this paper, the behavior of major elements and some indicator trace elements in three minerals including K-feldsapr, muscovite, and biotite belonging to the wall zones of Ebrahim Attar pegmatite have been studied.
Ebrahim Attar pegmatite was sampled. After polished thin sections preparation and minerals study, the contents of major elements and some trace elements such as Ta, Cs, Rb, Sr, Ba, F, and Cl in three minerals including K-feldsapr, muscovite, and biotite were measured using electron microprobe analysis (EMPA) in Russian Academy of Sciences. Finally, the analyzed data was interpreted.
In this section, the chemical composition of major oxides and some rare elements such as Rb, Sr, Ba, Ta, Cs, F, and Cl, has been investigated in order to considering the affecting processes on minerals concentration and determining the fractionation degree of the parental magma. The wall zones of the Ebrahim Attar pegmatite have low fractionation degree. During crystallization, the parental magma has interacted with mafic crustal materials and host carbonates. Increasing in Cl, Iron oxides, Mg, Ca, Mn, and Ti contents, resulted from crustal materials, have facilitated the circumstances for crystallizing the micas (especially biotite) and have prevented Ebrahim Attar transformation from peraluminous nature to highly peraluminous. So, the common economical minerals of a LCT pegmatite and tourmaline and garnet minerals haven't formed in the wall zones of Ebrahim Attar pegmatite. The poverty of Sr in parent magma has also contributed in this matter.
The parental magma of Ebrahim Attar pegmatite has interacted with mafic crustal materials and host carbonates and its fractionation degree had been low in wall zones. So, Al-bearing minerals such as tourmaline and garnet haven't engendered and LCT-type mineralizations haven't formed. Beryl concentration in intermediate and core zones confirms that the results which have been understood about a zone in a pegmatite aren't necessarily accurate for other zones or pegmatites of the studied region, because of heterogeneous distribution of crystals in the pegmatites.

Lower Miocene deposits in Iran have a significant expansion. In Zagros and Central Iran, these sediments include Asmari and Qom formations, respectively. Due to its economic importance and especially the possibility of reservoir and cap rocks, many studies have been conducted on the Miocene deposits in areas with high hydrocarbon potential. However, in the high Zagros, due to the limited oil reserves, the Miocene deposits have been less studied. According to the geological map of Harsin in the northern parts of the high Zagros zone (Shahidi and Nazari, 1997), the Miocene deposits consist of carbonate and clastic rocks. In terms of lithology, especially the presence of clastic rocks, these deposits are very similar to the Qom Formation, but since they are located in the high Zagros zone, it may not be correct to refer to this formation. On the other hand, the lithology and appearance of these deposits are fundamentally different from the Asmari Formation. Therefore, in this paper, like the geological map of Harsin, they are called Miocene deposits. In this paper, the paleoenvironment and microfacies of Miocene deposits in the high Zagros have been studied.

Three sections of Miocene deposits are studied, located 23 km south of Harsin (Figure 1). Fig. 1. Locality map of the studied area. In the present study, a total of 130 sections were taken. Thin sections were prepared from rock samples and isolated fossils were isolated from soft samples. Texture properties and fossil assemblages in thin sections were examined and identified by a polarizing microscope.BiostratigraphyBased on foraminiferal distribution, the following assemblage zones are recognized:1) Indeterminate Zone I: In view of the fact that we unable to find any index microfossils, comments on the age of this zone are difficult, which explains why this is here referred to as an indeterminate zone.2) SBZ25: Larger benthic foraminiferal zone SBZ 25 can be divided into two subzones; those of M. globulina and M. intermedia.2-a) M. globulina Subzone: This is defined by the FO of M. globulina at the base and the FO of M. intermedia at the top. It is regarded as a common global index for the Burdigalian Stage.2-b) M. intermedia Subzone: This is defined by the stratigraphical range of M. intermedia, which is considered to be a characteristic form for the middle-upper Burdigalian (Cahuzac & Poignant, 1997). 1) Indeterminate Zone II: In view of the fact that we could not find any index microfossils in this zone, we here refer to it as indeterminate zone. As to its stratigraphical position, we prefer an early Langhian date for this zone.2) Orbulina suturalis Interval Zone: Planktonic foraminifera are frequent to dominant in the upper part of the Sayl Cheshmeh section. Based on their vertical distribution, a single biozone has been recognized. This is defined by the FO of O. suturalis (Brönnimann, 1951) and ends right below the conglomerate/sandstone levels of Pliocene age

Depositional model:

Based on the field observations, petrographic studies and textural characteristics as well as the abundance and distribution of foraminiferal fauna and other components, 7 carbonate microfacies have been identified. These carbonate microfacies were deposited in4 facies belts including lagoon, margin facies, upper slope facies and lower slope facies (Fig. 2). Fig. 2. Depositional model for the platform carbonate of the Miocene deposits in the Harsin area, High Zagros Zone The stratigraphical position and vertical and lateral dispersion of different facies along with textural features and skeletal composition, and the presence of coral reef reefs and sudden change of facies and the absence of large tidal zones of Miocene deposars in Harsin area indicate that this sequence deposited on a rimmed carbonate platform.

Carbonates of the Asmari Formation form the youngest reservoir rock of the Zagros Basin (Ghazban, 2007). Various studies have shown that sedimentary geochemistry can be used to evaluate palaeotemperature and palaeoclimate by reconstructing the chemical and isotopic content of the ancient seawater and/or diagenetic fluids (Winefield et al, 1996; Adabi, 2004; Adabi and Mehmandosti 2008; Crowe et al, 2013; Swart, 2015; Fallah-Bagtash et al, 2020; Omidpour et al, 2021). The present study is based on a combination of different data such as core analysis, thin-section petrography, trace-element and stable-isotope analysis of Asmari carbonates to recognize the original carbonate mineralogy and diagenetic environment. 

In this study, 524 thin sections prepared from core samples of well-11 were used to achieve the desired goals. All thin sections were stained with potassium ferricyanide and Alizarin Red-S to dolomite and calcite minerals identification (Dickson, 1965). The nomenclature for carbonate rocks used in this work is a combination of the terminology introduced by Dunham (1962) and Embry and Klovan (1971), which is based on textural aspects. Facies analysis and interpretation of the depositional environment was performed using by Burchette and Wright (1992) and Flügel (2010) schemes. Based on the detailed petrographic results, forty-five limestones and thirty-two dolomites from well-11 were carefully selected for trace elemental analysis. Elemental analysis carried out using atomic absorption spectrometry (AAS) in the geochemistry laboratory in the Ferdowsi University of Mashhad for the major and trace element determinations. Forty-five powdered of the limestone samples, that were previously used for the major and trace elements, were analyzed with a VG STRA Series II for oxygen and carbon isotopes at the G.G. Hatch Stable Isotope Laboratory, University of Ottawa.

The detailed thin-sections analysis of the carbonate samples resulted in the distinction of 26 microfacies types in a subsurface section of the Shadegan Oil Field along that have been deposited along a homoclinal ramp-type platform and is divisible into an inner ramp, mid ramp, outer ramp and basinal settings.The bulk-rock oxygen and carbon isotopic analyses of the Asmari limestones are compared with similar analyses of the Asmari Formation in the Dezful Embayment (Aqrawi et al, 2006) and of other Palaeogene-Neogene carbonates (Veizer et al, 1999). It can be deduced from Figure 10 that the δ18O and δ13C values correlate well with those found by Aqrawi et al. (2006) for the Asmari Formation, but show slightly lower δ18O and δ13C values than those mentioned by Veizer et al. (1999) for the Palaeogene-Neogene carbonates. The geochemical and isotopic data allow, in combination with the petrographic data obtained from thin-section analysis, recognition of the primary aragonite mineralogy and the evolution of the rock fabric, as well as a reconstruction of the diagenetic evolution, temperature, the nature of the percolating fluids, and the water/rock ratio or diagenetic system.  The input of the δ18O-enriched samples (-0.85‰) within the Anderson and Arthur (1983) formula gives a syn-sedimentary temperature of only 23 °C. Based on textural and geochemical features four types of dolomite (D1 to D4) were identified in the sedimentary succession of the Asmari Formation. D3 (with high values of iron and manganese) is more affected by diagenetic alteration than the D1. Due to oxidizing conditions, iron and manganese values in D1 (near-surface) are lower than the burial dolomites (D3), which formed under a more reducing state at the greater depth of burial (Tucker and Wright 1990; Hou et al, 2016).