مجله پژوهش های دانش زمین
پیاپی 40 (زمستان 1398)

Climate change is one of challenging subjects that affect the vast majority of human life. It can influence the quality and quantity of surface water resources in particular rivers. Furthermore, El-Niño Southern Oscillation (ENSO) is considered as a climatic phenomenon that has significant effect on weather, climatic and hydrology changes. The impact of ENSO on discharge of rivers has been assessed in several investigations. Also, drought is known as a natural phenomenon influencing hydrological parameters such as surface water flow. Due these assessments, the main purpose of this survey is evaluating the impact of ENSO and drought indices on surface water changes.

Effect of ENSO and drought on discharge of hydrometric stations in Hamedan and Zanjan provinces during a 32-year period were assessed. For this purpose the standard precipitation index (SPI) and 9 ENSO indexes including SOI, PNA, MEI, NINO3, NINO4, NINO1+2, NINO3.4, TNI and  SST from 1981 till 2012 were evaluated.
Among existing drought indices, SPI is likely the simplest drought index because it can be compared across different climatic regions. It is designed to be a spatially invariant quantity that can be computed, to provide precipitation excesses and deficits during multiple timescales. The value of SPI was determined based on the following equation in DIP software:                                                                                                 (1)
Where, : amount of precipitation in time t, : average of long term precipitation, SD: standard deviation of data. 

Comparison of different ENSO indices affecting discharge changes, indicated that maximum correlation belonged to South Oscillation Index (SOI). In the second step, the average discharge of hydrometric stations in each phase of ENSO was evaluated.
According to the obtained result, it can be inferred that the El Nino has led to an increase in the discharge of both stations. The highest increase belonged to Vasaj station, by 345 percent. This value is in line with the report of Nazemosadat et al. (2006). Assessment of impact of drought on discharge of each station indicated that the impact of SPI on discharge changes is different in each station. So that in dry years, the amount of discharge of Bahador-Beyg and Tagsimab has decreased, in comparison to an increase in other stations. One of the reasons can be that the effect of non-precipitation parameters such as plant cover and geology on hydrologic changes.

In general, effect of ENSO on discharge changes was more than drought effect in a way which the average percentage of stations with significant correlation with SOI in Hamedan and Zanjan provinces were 36.5 and 42.42 %., respectively. On the contrary, the average percentage of stations with significant correlation with SPI in Hamedan and Zanjan were 24.5 and 24.83 %, respectively. Also, El Nino phase effect led to increasing discharge of hydrometric stations.

In recent years, extraction of groundwater resources as well as droughts in the Minab plain of Hormozgan province has led to a decrease in groundwater levels, a decrease in water quality and subsidence, resulting in social and economic problems for the people of this region. On the other hand, in some seasons, due to the flooding of the plain, large surface waters flow into the sea. Considering these issues, it is necessary to find suitable fields for artificial nutrition of the groundwater resources of the plain of Minab, so that artificial dams can prevent these waters and floods from entering the sea. Thus, they could feed the plain of Minab. This research studies Minab as a pilot to identify effective parameters and their use as indicators for determining the susceptible sites and ultimately determining the appropriate arenas for artificial nutrition using ArcGIS, Expert Choice and FUZZY -AHP.

a) Introducing study area
The Minab study area, as part of the Minab Plain, is located 100 km east of Bandar Abbas. This zone, with the code 2807, is one of 22 study areas in the central areas of the river basin between Bandar Abbas to the south, and is geographically located between the geographical longitudes '48 ° 56' and '15 ° 57 'east and the latitudes '00 ° 27 to '20 ° 27' north and east of Hormozgan province. The extent of the Minab study area is 654 km2. Minab aquifer, with an area of 272 square kilometers is the only aquifer in range. According to the summary of the changes in the size of the reservoir of Minab plain, a reservoir deficit of 8.876 (million cubic meters) and an annual water loss of 0.46 (m) for this plain are observed.
b)

There are various ways to locate suitable areas for artificial nutrition. The use of any method involves the integration of different information together and analyzing them. In addition to library studies, in order to identify effective parameters and use them as indicators for determining the susceptible sites and finally determine the appropriate arenas for artificial feeding, Arc GIS, Expert Choice and FUZZY-AHP were used. The steps of the FUZZY-AHP method in this study are summarized as follows:1. Determine the criteria and sub-criteria (layers and sub-layers).
2. Provide and prepare information layers.
3. Preparation of a questionnaire (Delphi method).
4. Weighing of information layers by AHP method.
5. Apply the final weight to the criteria.
6. Fuzzy Overlay Layers Integration.

Regarding effective factors in determining the areas of artificial feeding of the studied area, the research findings show that the geological criterion has the highest score (0.450) in prioritizing the effective parameters in artificial feeding of the plain area of the study area and, respectively, land use criteria (0.260), Hydrology (0.153), topology (0.079) and finally climate (0.058) have the lowest weight in prioritizing effective parameters. After mixing the layers with fuzzy method, a final layer was used to determine the proper places for artificial feeding. The final map was classified into 4 classes (inappropriate, medium, appropriate and very appropriate). The most common areas (49.55%) were inappropriate places, followed by a 21.7% of the middle class, 19.58% of the appropriate, and 9.17% of the very appropriate surface area for artificial nutrition.

The level of water change during the 30-year period was 13.85 m (13 m decrease in water level), which reduced groundwater levels, reduced water quality, caused subsidence and as a result created social and economic problems for the people of the area. Considering these issues, one of the most useful ways to preserve the discharge and maintain the groundwater resources of the area is artificial feeding system which, in addition of compensating for the excessive loss of aquifer and its rehabilitation, will attract the floods and reduce their destructive effects. According to the findings of the research, northwest and areas from the west of the study area of Minab, are the best places for artificial nutrition, accounting for only 9.17% of the total area of the range. The central parts of the research area are ranked appropriately and moderately appropriate, which are the next candidates for artificial nutrition. Inappropriate condition density is also seen in the east of the range.

Drought is a global phenomenon that is caused by the lack of precipitation and occurs in most landscapes. This phenomenon occurs in different climates and causes degradation of soils and natural resources (water and soil) and human life. Many of these drought effects are not directly caused by rainfall deficits, but are related to below-average storage conditions in surface water, reservoirs, and groundwater which are the consequences of the propagation of a meteorological drought into the hydrological system. Drought indices make transforming information of climatic anomalies easier and allow the scientists to assess the climatic anomalies quantitatively. For example, Nohegar and Heydarniya (2017), studied the evaluation of the effects of meteorological drought on groundwater table fluctuations. Bloomfield et al. (2019), considered the changes in groundwater drought associated with anthropogenic warming. In the absence of long-term changes in precipitation deficits, they infer that the changing nature of groundwater droughts is due to changes in evapotranspiration (ET) associated with anthropogenic warming. In this study, the seasonal variability of the groundwater level, and its relation with drought was studied for selected wells. The duration of drought events and lag times of groundwater responses, concerning the onset and termination of drought events, were also studied. The objective of this research is the analysis of drought conditions in Hashtgerd district, Iran, based on RDI and GRI. Meanwhile, the effects of Meteorological drought on groundwater resources have been studied as well.

The Hashtgerd Plane with a coverage of 1170 Km2 is located between 445667‘E and 508251’E longitudes and 3960289’N and 3996637’N latitudes in the southern part of Alborz province. The data was collected from 8 wells over the plain, while climate data were taken from Ghazvin weather station. The two well-known drought indices of RDI and SGLI were used. For determining the trend in time series, the Man-Kendall test was used. SPSS software was used for running Pearson correlation test and finding the correlation between groundwater level and drought indices. Finally, the simple linear regression between these mentioned time series was applied to determine the impact of different parameters on the groundwater level.

It should be mentioned that SGLI behavior is in accordance with groundwater. In some years, RDI is below zero lines, in which groundwater table depletion has occurred. In recent years, for most wells, the severity of the drought and its occurrence have increased. Increasing severity of droughts is equivalent to a decrease in the amount of SGLI, and increase in the number of years remaining in drought. According to the results, for the period of study, Qazvin Meteorological Station cannot be categorized in any of the drought classes (RDI values are more than -1). Also the correlation coefficient between drought indices has some fluctuations in 12, 24, and 48 months; however, NamakAlan well has the highest correlation with the index in 48 months’ period (0.7). The correlation between RDI and groundwater drought is the lowest for 1 and 3 months’ periods. Investigation of simple linear regression relation showed that 47% of the variance of average water level is affected by drought, and the remaining (53%) is the share of other factors. If the groundwater recharge in an aquifer is from the high elevated mountains (such as Hashtgerd Plain), expecting the short-term impact of a decrease or increase of precipitation on groundwater level in all wells in the region is practically incorrect. Therefore the contribution of other factors in reducing or increasing the water balance should be investigated. Given that part of the study area, plays the role of aquifer recharge, the selection of a few limited points to investigate the effects of precipitation, temperature and other meteorological variables (and even meteorological drought) on groundwater level will not yield desirable results, and small units should be selected and studied as far as possible.

In every society, human activity is the source of capital. Therefore Asnaaf is one of the manifestations of human activity as a capital. In the past, Asnaaf often consisted of owners of the professions that had broad social responsibilities and common benefits, with a legal institution. Asnaaf functions usually included laws, participation, education, political demands, cooperation, taxation, and general social functions. The trade union or guild system was established in the Italian city- states for the first time. These associations have played an important role in the growth of capitalism and democracy in the West, as an intermediary institution between the urban state and the urban trader. But today, the function of Asnaaf has decreased and faces depression, lack of support for production and capital. On the other hand, in modern cities, the Business Improvement Districts (BID) have management functions. Business Improvement Districts have specialty public-private participation, where business owners work together, to protect, develop, and enhance their business districts in cities. BIDs improve economic investment by improving investment and providing supportive and promotional services and activities and taxation systems. Actually the business improvement districts create a flexible financial mechanism to enhance the quality of life and business through partnerships. Therefore, urban development through Asnaaf, requires attention to the mechanisms of managing urban economic spaces in developed countries, which are also known as 'business improvement districts' or, 'BIDs'. Therefore, due to the conformity of Asnaaf characteristics with business improvement districts, this study, compares and evaluates the participatory mechanisms of Asnaaf and business improvement districts and provides solutions.

Data collection was conducted through library and documentary studies and the research method is qualitative, using content analysis. Content analysis is an inductive explanation method for discovering subjective data through coding and categorization. Also content analysis is a set of communication analysis techniques used to describe the content of a point.

So after conducting qualitative content analysis and coding in each of the relevant texts on Asnaaf in Iran, as well as the characteristics of business improvement districts, the concepts (subcategories) are categorized into four groups of socio-political, economic, Institutional - managerial and physical categories.

Accordingly, 16 sub-categories in social and political categories, 10 in economic categories, 10 in institutional-managerial categories and finally 4 concepts or sub-categories in physical categories have been extracted. In the research results, these items have been considered in local development planning, the participatory mechanisms of business improvement districts in Iranian Asnaaf, with a special emphasis on enriching civil society,good urban governance, entrepreneurship development, capital growth and social consensus and organizational commitment. Generally, using participatory mechanisms of business improvement districts to develop Asnaaf in Iran, is an attempt to localize development. So that Asnaf in Iran can act as business improvement districts (BID) and rebuild and regenerate cities.

Field methods and the use of seismic tools to determine tectonic activities in an extensive area is costly. Hence, the use of alternative methods including geomorphic indicators to determine and detect tectonic activities can be very beneficial. Many geomorphic indicators such as triangular surfaces, the surface leveling of the mountain front, the concavity of river profiles, pattern and drainage density, river longitudinal gradient, the ratio of the width of the valley to the height of the valley, the asymmetry of drainage basin, sinuosity of the mountain front, integral to the hypsometric, are used by researchers to determine tectonic activities and tectonic changes. The Talesh coastal basin is among the regions which are subject to extreme tectonic transformations due to the presence of numerous faults. Therefore, determination of tectonic activities of these basins are very important. The aim of this study was to evaluate the active tectonics, based on Morphotectonic and morphometry studies of catchment in the studied area. 

The study area of the Talesh Coastal unit, which stretches from the Sefidrud Valley to the Lankaran Basin in the Republic of Azerbaijan, extends from longitude 48° 22 ̋ 46 ̋ to 49° 23 ̋ 21 ̋ in east and latitude ° 51 ̋ 25 ̋ to 38° 51 ̋ 25 ̋ in the north.To achieve the objectives of this study, Alos-Polsar digital elevation model and HEC-GeoHMS software were used to extract 37 Basin and drainage networks and rivers of the studied area. Using morphometric indices, the calculation and analysis of the region’s morphotectonic were performed in 10.2 ARCGIS and Saga 2.1.2 Software. These indices include: the ratio of the width of the valley to the depth of the valley (VF), the ratio of Basin (Bs), asymmetry index of waterways (AF), the curve of the Hypmetric and Integral (Hi), River sinuosity Index (S) and Topography symmetry index (T). In order to evaluate and classify basins according to tectonic activity, the relative evaluation index of tectonic activities (IAT) was used in this study and the obtained results were validated with seismic data

Between the 37 sub-basins, 14 basins with an area of 2059 km2 (40.7% of study area) has high tectonic activity, 22 catchments with an area of 2979 (58.5 of study area) and has moderate activity and only one basin low activity. The overlap of the seismic data with the results of this study shows a good correlation with the fact that despite the low area of high tectonic activity basins (2059 km2 and 40.7% of the study area) about 71% of the large 2 seismic data were recorded.

The results of this study show that despite the exposure of multiple faults in this area, only 38% of the catchments are located in the field of active classification and other basins are between moderate to low tectonic activity. According to the IAT index, the most tectonic activity in Talesh basins in Iran are Chalasi and Emerald basins and Warcharand and Lankaran in the Republic of Azerbaijan. Overlap of seismic data with the results obtained from this research, show a good correlation.

Nowadays, sustainable rural development has a particular place in the development policies of countries responding to the challenges of classical development approaches such as poverty, unemployment, inequality, and environmental degradation. To overcome the unsustainability, diversification of the rural economy, based on the discovery, creation, and use of opportunities in the non-agricultural economic sectors of these areas is emphasized. According to the vast human and natural potentials of villages, the development of sustainable tourism in rural spaces, known as sustainable rural tourism, is a relatively new and growing opportunity to inject sustainability into these areas. Recognizing and benefiting from these opportunities is dependent on empowered and risk-taking villager entrepreneurs who are familiar with market potentials and demands, marketing practices, business models, income generation, etc.Besides, an appropriate environment is essential to improve their entrepreneurial behavior and entrepreneurship in the field of rural tourism. In this respect, sustainable entrepreneurship, which emphasizes the simultaneous creation of economic, social and environmental values, is a key strategy to achieve sustainable development. Therefore, in an entrepreneurial and sustainable-oriented context, sustainable rural tourism is capable to promote sustainable rural development through creation of innovative business opportunities in various fields such as accommodation, tourism, food, handicrafts, etc. Based on the behavioral or environmental entrepreneurship theory, such a context is influenced by numerous economic, social, environmental, physical, and institutional factors that need to be identified and prioritized for effective policymaking. Therefore, the study seeks to find factors which are effective in rural tourism sustainable entrepreneurship in settlements of Goleyjan rural district.

This is a fundamental, descriptive-analytical article. Documentary and field study methods were used for data gathering. The research instruments were observation and questionnaire. The statistical population is all residents of Goleyjan rural district (24304 persons) and the sampling method is stratified random, based on proportional sampling per size. The number of the sample was calculated by Cochran’s formula (379 persons). Data analysis was performed using descriptive statistics such as mean and standard deviation and Kolmogorov-Smirnov, binomial and Kruskal–Wallis tests and IDW interpolation technique by SPSS and GIS software.
 

According to the results, the mean of the factors affecting sustainable rural tourism entrepreneurship development, including economic, physical, infrastructural, social, environmental and institutional were 3.55, 3.50, 3.48, 3.46 and 3.46, respectively. Also, the results of the binomial test (criterion mean = 3) showed that the majority of respondents (97%) expressed the importance of the mean of these factors to be above average. The priority of economic factors, as well as the importance of all other four factors (environmental, social, economic, and institutional) for the development of entrepreneurship in rural tourism, are in line with the research results of Raknoddin et al. (2014). The results of zoning the importance of these factors in Goleyjan indicate that the economic dimension was the most important in the village of Isardeh and the least important in Chalaasar. Other social, institutional, infrastructural, and environmental dimensions had the highest average in Agha Moghim Mahale Village. In general, the average importance of these dimensions in different villages were not the same. Finally, the average importance of these dimensions in different villages were not the same.

This study investigates to determine the factors affecting sustainable rural tourism entrepreneurship development and their priorities. Regarding the more important economic, social, environmental, physical, and institutional factors, the planning and action, according to spatial priorities is essential. Ignorance of any of them can slow down the process of developing sustainable entrepreneurship in the rural tourism sector of the study area. Given the importance and priority of the economic dimension, it is necessary to promote public and private sector investment, expand financial support, provide facilities and pay off loans with low-interest rates. Furthermore, regarding other factors, developing extensive education in sustainable entrepreneurship and tourism fields, providing entrepreneurial advice and up-to-date information in business to villagers, reducing the required steps for setting-up a business, developing information and communication infrastructure, banking and tourism services and infrastructures are important.

In order to study the biostratigraphy, paleoecology and paleogeography of Qom formation ostracods, the Gonjan stratigraphical section was sampled and studied. 36 species and 23 genera of ostracods from Gonjan stratigraphical section have been studied and identified, which belong to two podocopid and platycopid orders. Based on the diversity of the identified foraminifera in this section and abundance of lepidocyclinids, the suggested age of  Qom Formation deposits in Gonjan section are Rupelian?-Chattian. The presence and abundance of ostracoda with larger benthic foraminifera, Coralline red algae and Corals indicates the oligotrophic to mesotrophic conditions in the tropical to subtropical environments, with normal salinity and oxygen richness during the deposition of the Qom Formation.The Qom Formation consisting of limestones, marine marls, gypsum and siliciclastics was deposited at the last sea transgression in the Oligo-miocene age, with northwest-southeast trending in three basins of Sanandaj-Sirjan fore arc, Urumieh-Dokhtar intra arc and Central Iran back arc.

In order to conduct this research, based on lithology of layers, 45 marly and calcareous samples were collected.

Qom Formation in the study area consists of five limestone and marl informal members. These informal members are lower limestone, lower marl, middle limestone, upper marl, and upper limestone. 36 species and 23 genera of ostracoda from Gonjan stratigraphical section have been studied and identified:Cytherella sp., Cytherella dissimilis, Cytherella strangulat, Cytherelloidea sp., Paracypris sp.A, Paracypris sp.B, Krithe sp.A, Krithe sp.B,  Trachyleberis sp., Ambostracon sp., Xestoleberis sp., Dentokrithe comma, Krithe trinidadensis, Loxocorniculum sp., Acanthocythereis sp., Buntonia sp., Loxoconcha ? sp., Cyprideis sp.A, Cyprideis sp.B, Actinocythereis sp., Actinocythereis iragensis, Legitimocythere sp., Parakrithe sp.A,  Parakrithe sp.B, Cytheridea josephina, Cytheridea eggenburgensis, Ruggieria sp., Bairdia sp.A, Bairdia sp.B, Bairdia rafidainensis, Loxoconcha psedohamrinensis, Loxoconcha hamrinensis, Aurila sp., Costa tricostata, Mutilus sp., Ambocytherea sp.

The presence and abundance of ostracoda with larger benthic foraminifera, Coralline red algae and Corals indicates the oligotrophic to mesotrophic conditions in the tropical to subtropical environments with normal salinity and oxygen richness during the deposition of the Qom Formation. Studies on the Qom Formation ostracoda in Gonjan section, indicate the similarity of these samples with other areas of Iran, India, north and north-east of Iraq, Turkey, eastern Mediterranean and North Africa. Thus it represents a seaway connection between these areas during Oligo-Miocene, which is considered as the Tethyan Seaway. The Qom Formation had a communicative role between Eastern Tethys and the Western Tethys region in the Iranian Plate.

Sanandaj-Sirjan zone is located in the southwestern margin of central Iran, which lies on the immediate northeast boundary of the main thrust of the Zagros Zone. Rock and structural features of Sanandaj - Sirjan zone represent a deep through or middle block rift in the Precambrian shield of Iran and Saudi Arabia.The northern boundary of this zone is separated by the Urmieh-Dokhtar Volcanic Belt and the Sirjan, Marvdasht, Gavkhuni, and Mighan Desert embayment and its southern boundary is the Zagros thrust Fault.The sedimentation regime and structure of the Sanandaj-Sirjan zone are similar to those of central Iran. In addition, all of the major Mesozoic and Tertiary discontinuities present in central and northern Iran are also known in this zone, which some of them are absent in Zagros.Material and methods   Eocene sedimentary deposits in two sections of Sanandaj-Sirjan zone in Soh area of Kashan with a total thickness of 171 m and in Zefreh area of Isfahan with a total thickness of 40 m were among the areas that were identified as suitable for this study.For paleontological, microfacies, and sequence stratigraphy studies, 42 samples from the Soh section and 58 samples from the Zefreh section were taken for thin section preparation. For the study of microphysics, Dunham's (1962), Embrio Clown's (1971), Wilson's (1975) and Flügel's (2004) methods were used.To select samples with low alteration, a number of micritic sections were selected for study by Cathode Luminescence (CL) method. In this study, it has been attempted to analyze stable carbon and oxygen isotopes in sediments and to find information on the paleontological temperature and diagenesis process in the area.The abundance, diversity and high degree of evolution of large foraminifera have made these foraminifers very useful tools in biostratigraphy to determine the age of sediments deposited in shallow marine platforms; therefore, for the time range from the early Paleocene to the Eocene-Oligocene boundary, 20 Shallow Benthic Zones have been identified with the SBZ abbreviation. Basically an SBZ region is characterized by stratigraphic distribution of several taxa belonging to alveolinids, nummulitids, and orthophragminids.Results and DiscussionThe Eocene sedimentary facies in the studied sections consists of 8 facies belts that are from sea to coast: Marly Maudstone facies (F1), Bioclastic (nummulitids-discocyclinide) wackestone-packstone facies (F2), Bioclastic (small rotaliids-miliolid) peloidal wackestone-packstone facies (F3), Alveolina-Coskinolina-Dictyoconus wackestone-packstone facies (F4), Conglomerate facies (F5), Sandstone facies (sandstone) (F6), Siltstone facies (F7) and Red Mudstone facies (F8). The sedimentary model is considered suitable for Eocene sediments in Soh, and Zefreh areas are open shelf zones. Based on the identified microfacies and the distribution of organisms, this open plateau is divided into three parts: outer, middle, and inner. The sedimentary model considered for the Jahrum sequence in the Zafreh and the Soh deep-to-shallow zones is the outer shelf environment, including the Marly Mudstone which belong to the very deep shelf area. ConclusionThe bioclastic (nummulitid-discocyclinid) wackestone-packstone facies also belong to the middle shelf area. The bioclastic (small rotaloiides - miliolids) peloidal wackestone-packstone facies and Alveolina-Caskinolina-Dictyoconus-wackestone-packstone facies belong to the inner shelf. Coastal facies also include conglomerate, sandstone, siltstone, and red mudstone.Finding suitable specimens in the Sanandaj-Sirjan zone was difficult because of the more severe diagenesis than the Zagros specimens.Since even these samples were altered by very low degrees of diagenesis, the resulting temperature could not reflect the paleo-temperature of the sedimentary environment, Therefore, to calculate the initial temperature of diagenesis, the lightest oxygen isotope (18O) in (PDB) -9.34‰ for the Soh cross section and (PDB) - 9.9‰, was used for calculating the initial diagenesis temperature for the Zefreh cross section. Accordingly, the temperature obtained for the Soh is 66 ° C and 64 ° C for the Zefreh. This high temperature in the Sanandaj-Sirjan zone not only aggravated the diagenesis process but also caused severe discoloration in many of the foraminifers' samples in this zone.Sequence stratigraphic studies resulted in three sequences: sedimentary sequence 1 (DS1), sedimentary sequence 2 (DS2) and sedimentary sequence 3 (DS3), respectively.

The Milajerd prospecting area is located within 100 km of western Ardestan and belongs to Naein-Natanz prospecting region. This area is one of the favorable target areas that have been defined by multidiscipline GIS-based metallogenic modellings for metallic resources. This area consists of two main zones with different geologic and geophysical (magnetic) characteristics. The first zone (on the west and south) presents sialic continental crust with Gondwana-type Paleozoic-Middle Triassic epi-platform sediments that is covered by Eurasian-type Upper Triassic to Lower Jurassic coal-bearing silici-clastic series of Nayband Formation. The Nayband Formation is overlaid by Cretaceous conglomerate -sandstone beds that are followed by limestone and marls upward.  The conglomerate and sandstone beds present angular unconformity with Nayband and older formations. The second zone on the east and north belongs to Molla-Ahmad-Karkas arc-type volcano-plutonic belt, which is composed of intermediate to acidic Eocene volcanic series that have been intruded by Late Eocene to Miocene granitodes.

The Milajerd Pb-Zn±Au polymetallic prospecting zone in Naein-Qom Magmatic Zone is one of the favorable targets defined by multidisciplinary metallogenic modellings for gold and base metal resources. Ground controlling of the aforesaid target area has been carried out by coarse 1000*1000 m2 grid litho-geochemical surveying. A total of 176 rock-chips samples each weighting 1500gr were collected. Each of them was  assayed by ICP AES method  in Kanpazhuh Laboratory for  Au,As,Ag,Ba,Pb,Zn, Cu,Mo, Ni,Co,V,Ti,P,Bi,Cr,Fe,In,La,K,Na,Mg,Mn,S,Sb,Sc,Sr,Th,U,W,Zr.

The main approach for evaluating the favorability and mineral resources, was data processing and information analysis based on defining “Polarized Geochemical Systems (PGS) and related depleted, background and enriched zones. These zones are spatially forming unified systems referred to as” PGS” and present localities of ore deposit formation. According to the defined PGS, there are four systems with three expected types of ore mineralization; 1) porphyry Cu-Mo-(Au), 2) contact- halo Polymetal, and 3) epithermal gold ore formation. There is good correlation between lost copper in depleted zones and its concentrated amount in enrichments zones.

It is estimated that the depleted value would be almost equal to 1,969,800 t that is probably accumulated in enrichment zones. The tonnage of enriched copper is estimated to be 2,063,500 t (probably originated from Eocene-Miocene volcano-plutonic rocks and the Crust), almost equal to depleted value. These values could be considered as the key criteria to assess the favorability of the prospecting area for aforesaid-types’ ore mineralization.

Epithermal deposits have been studied by several researchers and their properties have been considered in various respects (Silito & Hednoquist, 2003; Hednoquist et al., 2004).One of the metamorphic magmatic zones in Iran that has always been considered by researchers, is the Urumih-Dokhtar magmatic belt (Bazin & Hubner, 1969; Amin al-Raiei et al., 2017). This belt, as part of the Tethys belt, is one of the most important metallogenic belts in Iran.Recent studies in the Shojaabad region, include Zamani studies (2013). In this research, the geochemistry and genesis of Cu-Au Index of western Shojaabad has been studied and classified as one of the porphyry deposits in relation to one of the Oligomiocene-Miocene intermediate-acidic intrusive rocks.Based on the location of the Cu-Au Index located in the middle part of the Urumieh-Dokhtar belt near to the Natanz Fault, alteration studies, geochemistry, mineralization and fluid inclusions were carried out in the area and finally genesis of the Cu-Au Shojaabad index was determined.

During field investigations, 20 sample of rocks were randomly sampled from mineralization outcrops and hydrothermal alteration zones. Then, thin and polished thin sections were prepared. In order to highlight hydrothermal alteration, Aster data of study area was prepared and final map of alteration zones was drawn in ArcGIS environment.In the next step, more than 10 samples were selected for geochemical studies. The samples were analyzed by X-ray fluorescence (XRF) method at the University of Isfahan to determine the amount of major elements. Also, to obtain trace and rare earth elements, samples were examined by ICP-MS method at ACME Laboratory of Canada. Moreover, in order to evaluate the formation temperature and the nature of mineralization fluids in the region, 6 samples were selected to study the fluid inclusions. Thermometric measurements of fluid inclusions were carried out in the Department of Geology of Isfahan University.

According to field surveys and microscopic studies, dominant rocks of the area include volcanic and pyroclastic rocks. The volcanic rocks are often porphyritic and exhibit a more rhyodacitic composition based on microscopic studies.According to the field surveys, processing of ASTER images, and microscopic studies, the presence of argillic alteration in the center of the region and the extension of propylitic alteration around the area is evident.The main texture observed in the ore of the area is disseminate texture. Other textures include replacement, zonal and veinlet textures.Thus, mineralization in the Shojaabad area is disseminated and often associated with quartz veins.
Based on the petrographic studies of fluid inclusions, they are predominantly primary fluids and low secondary fluids.The studied fluids’ inclusions are mainly from liquid-rich type, indicating that the mineralization in this region was by hydrothermal solutions and that the mineralization temperature was not high (up to 268 ° C).The homogenization temperature for the two-phase fluid inclusions was 187 to 268 ° C and the salinity was 1.6 to 10.5 wt% NaCl. For the determination of genesis of Shojaabad index, Kesler diagram was used (2005). It is clear that the most concentrated fluid inclusions are in the seawater domain. The magmatic fluid is probably in this range due to cooling and dilution by fluids with less salinity (atmospheric waters). The most important application of fluid inclusions is to determine the characteristics, and evolution of hydrothermal fluids and ultimately the origin or genesis of the deposit. Based on the temperature results obtained from the fluids’ inclusions (homogenization temperature below 300 ° C) as well as low salinity in the region, the study area appears to be part of the epithermal reservoirs.

Mineralogical studies indicate hypogene mineralization with pyrite, chalcopyrite and magnetite minerals and supergene stage with presence of chalcocite, covellite, malachite, hematite and goethite minerals.Based on the fluid inclusion studies, important factors such as the low existence of sulfide minerals in the form of fine and scattered crystals and large amounts of carbonate minerals around the ore mineralization, the Shojaabad index can be considered as low sulfidation epithermal deposits.

Protolith investigation of metabasitic rocks and identification of their geodynamic setting is one of the significant subjects in metamorphic petrology and several tectonic discrimination diagrams have been invented in order to attain this goal. Metamorphic complex of North Asadabad is regarded a part of Sanandaj-Sirjan zone that cropped out in western Hamadan. Sanandaj-Sirjan belt is the most dynamic block of Iran’s tectonic zones and has experienced important compressional-extensional and magmatic events during Neotethys subduction.
 

Metamorphic rocks of this complex are mainly metapelite and there are some restricted exposures of massive and foliated metabasites in this complex as well. Amphibole, plagioclase, chlorite and epidote are rock-forming minerals of these metabasites that are indicators of greenschist facieses metamorphic conditions. Plagioclase composition is albite and amphibole is from tremolite and edenite types. Chemical composition of amphibole and plagioclase are compatible with greenschist facieses’ metamorphic conditions, which are isofacial with respect to the adjoining metapelites.

Whole rock chemistry of 10 metabasitic samples from north Asadabad metamorphic complex were evaluated via ICP-MS method. According to the whole rock geochemical data, metabasites of NW Asadabad are of orthoamphibolite type and contain mostly alkali basal compositions. The patterns of REE and multi-elements spider diagram exhibit subduction-related characteristics. Geochemical signatures of these metabasites are compatible with intra plate and continental plate margin tectonic settings.According to modern tectonic setting discrimination diagrams and those logarithmic diagrams that have been based on multi-elements, the protolith genesis of metabasite from north Asadabad metamorphic complex is mostly linked to the subduction setting. Metabasite with subduction geochemical signatures, have been reported from the rest localities of northern Sanandaj-Sirjan zone like Songhor-Kangavar, Saghez-Pyranshahr and Shahindezh as well.

Probably, metabasites from NW Asadabad, are representing a mafic magmatism in the continental back arc setting, arising from Neotethys oceanic basin subduction beneath continental lithosphere of Sanandaj-Sirjan zone, which has subsequently undergone collision or continental active margin metamorphism.

abstract Northwest of Iran, especially Talesh zone, is one of the important Alkaline and Shoshonite magmatic activity area in the Cenozoic. Eocene - Oligocene Gabbroic rocks in the south of the city of Germi as part of the Talesh zone have penetrated the Eocene alkaline basalts. Alkaline basalts with hyalomicrolitic porphyrytic and glomerulophorphyric texture are composed of plagioclase and clinopyroxene with lower amounts of olivine minerals, dark minerals, black mica, amphibole and alkali feldspar. Gabbro masses have granular texture containing pyroxene minerals, plagioclase, black mica, amphibole and ± alkaline feldspar. Composition of all these rock outcrops are alkaline to shoshonite. The studied micaceous of south Germi, based on the chemical classification with Fe #> 0.33, have biotite composition at the interface between the two poles of sydrophyllite and stonitis, which, according to the evidence of petrography and chemical composition, coexist with amphibole. The chemical composition of these biotite is indicative of the nature of alkaline and magnesium host magma and have been crystallized from primary magma with respect to AlVI <1 values. In all studied samples, the amount of Mg # ranged from 53 to 67%, the Al Total value ranged from 2.4 to 2.58 and Fe # ranged from 0.33 to 0.47. The presence of Fe3 + in the structure of hic biotite from 1.73 to 2.23 indicates high fugacity values of 10-15 until10-17 for Ghafar Kandi gabbroic rocks and between 10-13 until 15-10 for Gabbro and basalts of Marallo with buffering of hematite and Magnetite. The studied biotites is chemically similar to the biotite samples of the Roman-type and the Marand Potassic rocks, indicating the dependence of the magma to the subduction environment.

Until now, many researchers have used organic geochemistry to increase exploration efficiency by accounting for many variables, including source rock quality and richness, thermal maturity, and the timing of generation-migration-accumulation relative to trap formation. The Sarvak and Mishrif Formation is one of the main Cretaceous carbonate promising reservoirs in the Abadan Plain and Mesopotamian Basin. Considering limited studies describing the Abadan plain petroleum system and lack of oil-oil correlation between Sarvak and Mishrif oil reservoirs, in this study, initially the quantity, quality and maturity of organic matter in candidate source rocks were investigated and then the geochemical properties of Sarvak oils were evaluated. Finally correlation study was performed on Sarvak and Mishrif oils.

Two oil samples in the Cretaceous Sarvak Formation from the west of Abadan Plain oil fields have been analyzed using Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). In addition, twenty cutting samples from candidate source rocks in the area from the lower Cretaceous and the upper Jurassic have been studied for source rock analysis.

The final interpretations of rock evaluation data for candidate source rocks in Abadan plain are as follows:Garau formation has good to excellent potential for hydrocarbon generation (mostly oil and less gas).Fahliyan formation has poor to fair potential to generate hydrocarbons. Although it is mature but the organic richness of the rocks are not enough and have generated relatively low amounts of hydrocarbons.Gadvan formation is evaluated as having poor potential source rocks and no oil could have been generated from these clastic rocks.Kazhdumi formation evaluated as fair to very good potential source rock, but being thermally immature and no hydrocarbon could have been generated from this rock.The biomarker analysis shows that Sarvak oils have been sourced from mature carbonate rocks containing Kerogen type II and were deposited in a low salinity environment. Also, based on C28 and C29 steranes and ETR, Sarvak oils were generated from Jurassic source rocks. According to biomarker and source rock studies, Sargelu and Garau formations were introduced as main source rocks in the west of Abadan plain, which generated Sarvak oils in maturity levels of early to middle oil window. On the other hand, biomarker data of five Mishrif oils from Iraqi oil fields (taken from released paper) were collected to compare them with Sarvak oil biomarkers.

The observations have been suggesting excellent correlations between Sarvak and Mishrif oil biomarkers, so according to close proximity of oil fields and rock evaluation data similarities, all generation levels, migration and accumulation of hydrocarbons in Sarvak and Mishrif reservoir located in the west of Abadan Plain and Mesopotamian basin respectively, are similar to each other. Finally, Sargelu and Garau formations generated hydrocarbons and are likely to have charged upper traps such as Sarvak reservoir, probably during Miocene, along faults and fractures.

The northern Kabudan ore mineralization has occurred in part of the Taknar structural zone in NE Iran and part of the Central Iranian structural zone (Stocklin, 1968; Berberian and King, 1981). The Taknar zone has been known for mainly acidic submarine volcanoes (Malekzadeh Shafaroudi, 2003; Karimpour et al., 2003) and the north Kabudan mineralization has been introduced as volcanogenic massive sulfide ore deposit (Heidarpour, 2012). In this research, mineralogy, mineral chemistry and geochemistry of ore deposits have been studied. Kabudan Fe ore mineralization district with average grade of about 45 wt. % is located in part of the Taknar volcano-sedimentary Formation (micashist units, dacitic-rhyolitic volcanic units and a complex of granite-granodiorite-metadiabase to metagabbro-dioritic intrusive bodies). Magnetite mineral chemistry in Fe ore deposits can be used on genesis of ore mineralization.
Analytical

A total of ninety microscopic sections were prepared from ore, geological units and alteration zones and studied at the Iranian Mineral Processing Research Center, using Axiplan 2 Zeiss microscope. For mineral chemistry, selected polished sections were studied by SEM (SEM 1450 VP) and EPMA (CAMECA X 100) electron microscopes at the Iranian Mineral Processing Research Center. In order to identify the mineralogical phases at the alteration zones, eighteen samples were studied by X-ray diffraction (XRD) method at Mashhad Geological Survey and Iranian Mineral Processing Research Center. For geochemical studies of ore, about 31 rock samples were taken from the ore mineralization zones and analyzed at the Geological Survey of Iran.

Ore mineralization had occurred as hypogene and supergene polymetallic (iron-lead-zinc-copper). Mineralization was seen at the specific horizons of Taknar Formation (sericite schist and chlorite schist) and metavolcanics associated with the Teknar Formation, as layered, massive and stockwork textures. Paragenetic sequences in layered and massive zones are: magnetite±hematite, pyrite, chalcopyrite, shpalerite and galena. Magnetite is the main and abound mineral in the massive zone. Pyrite, chalcopyrite and minor magnetite are main minerals in stockwork zone. Malachite and Fe-oxy-hydroxide associated with cerussite are formed as fracture filling and supergene zones. Electron microprobe results of magnetite show that the MgO contents are ranging from 0 to 0.77 wt. %, Al2O3 contents are ranging from 0.01 to 2.55 wt. %, TiO2 contents are ranging from 0.06 to 0.06 wt. %, V2O5 contents are ranging from 0.06 to 0.06 wt. %, FeO contents are ranging from 20.01 to 30.60 wt. % and finally Fe2O3 contents are ranging from 69.21 to 80.31 wt. %. Based on the results of the magnetite chemistry on geochemical diagrams by Dupuis and Beaudoin (2011), Kabudan-Bardaskan ore mineralization is classified as iron-rich volcanogenic massive sulfide. Geochemistry of ore indicate that Pb-Zn, Sb with As, Au and Fe and Zn-Mn pair elements have highest correlation coefficients and Cu-Mn and Bi with Sb- Fe and Ag have low correlation coefficients, which have been confirmed by microscopic studies.

Structurally, north Kabudan polymetallic ore mineralization (iron and base metals), is part of polymetallic Taknar zone in which iron, copper, lead and zinc mineralization occur as three forms: layered, massive and stockwork in the several different outcrops. The stockwork ore mineralization mainly consists of pyrite and chalcopyrite. Layered ore mineralization consists of magnetite, hematite associated with chlorite, carbonate and quartz as gangue minerals. The massive ore mineralization consists of magnetite, hematite, quartz, chlorite and quartz. Mineralization in Kabudan district is introduced as volcanogenic massive sulfide ore deposit due to presence of stockwork texture at lower depth and the layered and massive in the upper part, the existence of chlorite-sericite-carbonate alteration, simple mineralogy including chalcopyrite, pyrite, magnetite, galena and sphalerite and the presence of felsic volcanic rocks and basic metamorphosed subvolcanic and magnetite chemistry data. Considering differences with Kuroko, Besshi and Cyprus volcanic-hosted massive sulfide types, these facts indicate that ore mineralization in north of Kabudan can be classified as magnetite-rich massive sulfide ore deposits alike Balcooma, Gossan Hill and Noranda ore districts (Abitibi, Canada) (Morton, 1987; Huston et. al., 1992; Large, 1992; Huston, 2002; Sharpe and Gemmell, 2002).