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Open Access Article

1 - Petrography, geochemistry and petrogenesis of Abbas Abad volcanic rocks (East Shahroud) with emphasis on associated alteration and copper mineralization
Rasa Alirezaei Ahmad Kazemi Mehrnia لیلا صالحی

Abbas Abad ore district lies in a volcanic and volcanosedimentary belt in East Shahroud and hosts eight copper deposits. This belt is part of volcanic arc in north of central Iran. Copper mineralization is dominated by chalcocite with minor bornite, digenite and covelli More

Abbas Abad ore district lies in a volcanic and volcanosedimentary belt in East Shahroud and hosts eight copper deposits. This belt is part of volcanic arc in north of central Iran. Copper mineralization is dominated by chalcocite with minor bornite, digenite and covellite. Mineralization occurs as disseminated, veinlet, and stock works. Four alterations (silicification, carbonatization, epidotization and chloritization) are detectable in the host rocks. Lithologies of the volcanic rocks are trachyandesite, trachyandesit basalt and trachybasalte and they have high potassium calc-alkaline to shoshonitic nature. Fractional crystallization and crustal contamination processes are involved in magma evolution. Plagioclase and pyroxene are main minerals and the most important texture (porphyric and glomeroporphyritic) has been observed in this rocks. Zoning, sieve textures and re-absorption in plagioclases, and sieve textures, the effects of corrosion on the margins of pyroxene, and roundness of mineral implies the existence of non-equilibrium conditions during solidification of magma. LREE and LILE enrichment and depletion of HFSE with negative anomalies of Nb, Ti and Ta elements in studied samples show the alkaline nature associated with arc (active continental margin). Ratio of Ba/La and Th/Ta in rocks confirm subducting continental arc for tectonic environment of this rocks. Manuscript profile

Open Access Article

2 - Diagenesis, microfacies and determination of original carbonate mineralogy of the Asmari Formation in the southern flank of Rig anticline
Kakemem hamid mirmohammadsadeghi

The aim of this study is to recognize diagenetic processes, microfacies and geochemical evidence for original carbonate mineralogy of Oligocene- Miocene Asmari limestone deposited in the Rig anticline at Rig mountain oil field. In this area, the Asmari Formation with a More

The aim of this study is to recognize diagenetic processes, microfacies and geochemical evidence for original carbonate mineralogy of Oligocene- Miocene Asmari limestone deposited in the Rig anticline at Rig mountain oil field. In this area, the Asmari Formation with a thickness of 364 m have been exposed as a sequence of thin, medium, thick, and massive carbonate rocks. Twelve microfacies types have been distinguished on the basis of depositional textures, petrographic analysis and fauna. These carbonate microfacies belong to four major sub-environments including tidal flat, lagoon, bar/ shoal, and open marine. Absence of turbidite deposits, reefal belt and gradual changes in facies indicated that the Asmari Formation was deposited in a homoclinal carbonate ramp environment. The main diagenetic processes includes: dolomitization, cementation, micritization, dissolution, and compaction. Petrographic evidence and variation of major and minor element and compare this information with modern aragonite warm water and calcitic cool to cold temperate carbonate and originally aragonite mineralogy of Ordovician sub-tropical carbonate, the calcite mineralogy of Permian sub-polar cold water of Tasmania, the Upper Jurassic aragonite Mozduran limestone, the Ilam carbonate formation, and the Fahliyan Formation indicate that original carbonate mineralogy was aragonite in the Asmari Formation. High Sr/Na ratio suggests original aragonite mineralogy. Variation of Sr and Na values versus Mn confirm replacement of aragonite by calcite during the two stages of diagenetic stabilization. The bivariate plot of Sr/Ca versus Mn shows that Asmari limestone have been influenced by meteoric diagenesis in a closed to semi-closed diagenetic system. Manuscript profile

Open Access Article

3 - Geochemical Studies of Stable Isotopes (Carbon and Oxygen) in Mahallat Travertine Deposits (South East Arak)
لیلا صالحی

Fresh water carbonates are different in geochemical characteristics, especially in isotopic geochemical characteristics. Stable carbon and oxygen isotopes of carbonates such as travertine is one of the most important methods of study. Mahallat area with large traverti More

Fresh water carbonates are different in geochemical characteristics, especially in isotopic geochemical characteristics. Stable carbon and oxygen isotopes of carbonates such as travertine is one of the most important methods of study. Mahallat area with large travertine deposits, is talented to geochemical studies. this area is located in the southeast of Arak and this is a part of central Iran structural zone. Based on stable isotope studies, there are two types of travertine: thermogene and meteogene types. Thermogene C-isotope composition range between -4 ‰ and 8 ‰. However, δ13C value for meteogene type range between -11 ‰ and 0 ‰. Mahallat area travertine C-isotope composition range between 1.69 ‰ and 9.70 ‰ which indicate thermogene type. In addition, Another way to distinguish the type of travertine, is determination of carbon dioxide source. Low values of 〖〖δ^13 C〗_( CO)〗_2 imply to thermogene type and 〖〖δ^13 C〗_( CO)〗_2 Mahallat area travertine show -8.47‰ and this confirm thermogene type for these deposits. Also, water temperature during the travertine precipitation can calculate by oxygen isotope study. The temperature in Abegarm travertine is 43°C which it is evidence for thermogene type. Manuscript profile

Open Access Article

4 - Petrology and geochemistry of igneous rocks in Lower Red Formation, Garmsar Area
Habibollah Ghasemi

Numerous shallow depth basic intrusions crops out in the Lower Red Formation in Garmsar area. These intrusions have gabbro-dioritic compositions and granular, intergranular, ophitic and subophitic textures. Plagioclase, augitic clinopyroxene, amphibole and biotite are t More

Numerous shallow depth basic intrusions crops out in the Lower Red Formation in Garmsar area. These intrusions have gabbro-dioritic compositions and granular, intergranular, ophitic and subophitic textures. Plagioclase, augitic clinopyroxene, amphibole and biotite are their main minerals and olivine, phlogopite, alkali feldspar, apatite, magnetite and sphene are their minor and accessory minerals. Their secondary minerals composed of serpentine, zeolite, chlorite, sericite, prehnite, sphene, uralite, quartz and calcite. These rocks plotted in gabbro-diorite realm in chemical classification diagrams. Geochemical trends of samples in major and trace elements variation diagrams versus differentiation index and in incompatible-incompatible and incompatible-compatible diagrams indicate the liquid line of descent and differentiation relations between samples. In the chondrite and primitive mantle normalized diagrams, enrichment in LREEs and LILEs, depletion in HREEs, absence of Eu anomaly, positive anomalies in K, Ba, Rb and Sr in all samples and strongly depletions in Nb and Ta in some samples and absence of depletion in Ti and P, are the characteristics features of these rocks. This indicates the crustal contamination of the mafic mantle magma formed these rocks. These rocks rather have the features of proto-back-arc basin (BAB) alkaline basaltic magmas, not the characteristics of the subduction related rocks. The dependence of these rocks to the back-arc basin basalts can be confirmed by different tectonic setting discrimination diagrams. It seems that the primary basic magma of these rocks has been generated from partial melting of an enriched mantle source under the continental lithosphere of Central Iran in an extensional proto-back-arc basin, during Late Oligocene time and intruded in lower part of Lower Red Formation. Manuscript profile

Open Access Article

5 - Investigation of geochemistry of minor and trace elements (rare earths) in the base metal vein mineralization Yaralujeh area (NW Ahar - East Azarbaijan)
Zohreh Jabarzadeh Mehadi Moradi Moayyed Zargar Faramarzi

The Yaralujeh vein index is located about 40 km NW of Ahar, East Azarbaijan. Based on geochemical studies, the original host rock is microdioritic in composition with calc – alkaline character, situated in an active continental margin volcanic arc. The mineralization i More

The Yaralujeh vein index is located about 40 km NW of Ahar, East Azarbaijan. Based on geochemical studies, the original host rock is microdioritic in composition with calc – alkaline character, situated in an active continental margin volcanic arc. The mineralization is occurred as disseminated, stockwork and veins - veinlets containing quartz, carbonate and sulfide minerals in altered subvolcanic rocks (microdiorite). Pyrite, sphalerite, galena and chalcopyrite are the most important sulfide minerals in this area. The most important alerations in this area are sericitic and carbonatization, and the main alteration minerals are quartz, sericite, illite, albite, kaolinite, leucoxene, pyrite and late carbonates. Bivariate diagrams of Ba + Sr vs. Ce + Y + La and Zr vs. TiO2 and also values less than one for TiO2 indicate a hypogenic origin for altered fluids. The spider diagrams of REEs, normalized to both chondrite and average upper continental crust, show differentiation of LREE from HREE and depletion of LREE relative to average upper continental crust. Based on geochemical indicators such as Hf / Sm, Nb / La and Th / La and LREE enriched relative to the HREE, the most important ion complexes transition metal are Cl- complexes. Ce, Eu and Pr (Eu/Eu*, Ce/Ce*, Pr/Pr*) anomalies in ore-bearing vein and host rock indicates near-neutral pH in a redox environment for the alteration fluids in Yaralujeh Index. Manuscript profile

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6 - Mineral chemistry and P-T estimation of formation of garnetschist Mount Argon (west of Angoran Mine)
Moazzen Izadyar

The Mount Argon garnet schists contain mineral assemblages of quartz, feldspar, mica and garnet. The chemical composition of, plagioclase, biotite, muscovite and garnet in the studied sample shows that plagioclases are albite-rich, white mica flakes are rich in muscovit More

The Mount Argon garnet schists contain mineral assemblages of quartz, feldspar, mica and garnet. The chemical composition of, plagioclase, biotite, muscovite and garnet in the studied sample shows that plagioclases are albite-rich, white mica flakes are rich in muscovite end-member, phlogopite-annite is the dominant constituent in biotite and chemical composition of the analysed garnets shows that they are almandine and spessartine-rich. Maximum and minimum pressure and temperature of the studied rocks were estimated by using common calculation methods. The minimum and maximum temperature of metamorphism was calculated using Mg-Fe exchange between garnet and biotite. Considering a nominal pressure of 4 kbar, the highest calculated temperature was 615C and the lowest temperature was 380C. These were 644C and 392C for pressure of 8 kbar respectively. Also using multi-equilibria calculations, temperature of 800C and pressure of 9kbar were obtained for the peak of the metamorphism and temperature of 450C and pressure of 7kbar was calculated for the lower part of the metamorphism. . Two phases of metamorphism and deformation affected these rocks. The second deformation was associated with the peak of metamorphism. A decrease in temperature about 351°C with reduced pressure of about 2 Kbars is observed in the metapelitic rocks. Manuscript profile

Open Access Article

7 - Geo-thermo-barometry in Jebale Barez plutonic complex by using amphibole and feldspars chemistry
جمال رسولي aboozar ghorbani Vahid Ahadnejad

Jebale-Barez plutonic complex is composed of granitoid intrusive bodies and is located in the East and southeastern of Jiroft province of Kerman. The plutonic complex is composed of granodiorite, quartzdiorite, granite and alkaligranite. Plutonic rocks are mainly com More

Jebale-Barez plutonic complex is composed of granitoid intrusive bodies and is located in the East and southeastern of Jiroft province of Kerman. The plutonic complex is composed of granodiorite, quartzdiorite, granite and alkaligranite. Plutonic rocks are mainly composed of plagioclase, alkali-feldspar, biotite, amphibole and quartz. Based on microprobe analysis, plagioclases vary from andesine to labradorite and alkali feldspars occur as orthoclase. All amphiboles are magmatic and placed in three groups: calcic amphiboles, iron-rich amphiboles, amphiboles consist of Fe, Mg, Mn. The study of oxidation and reduction state of their source magma by amphibole chemistry, in dicated high oxygen fugacity. Therefore, granitoids of Jebale-Barez plutonic complex are I-type or related to magnetite series and the estimated oxygen fugacity imply oxidation magma and its formation in convergent plate boundary. On the basis of geo-thermo-barometric calculations, using Hamarstrom - Zen, Schmidt, Johnson - Rutherford, Smith - Anderson and Uchida methods, amphiboles have crystallized about 1.54 to 7.87 kbar at the depth about 18 to 23 km. As emplacement or crystallization temperature of Jebale-Barez plutonic complex based on the two feldspar thermometer using Anderson method has been ranges between 550 to 750 ºC and using Putirka method has been achieved between 710 to 830 ºC and based on Ti-in- amphibole thermometer has been ranges between 670 to 735 ºC. In addition, hornblende -plagioclase thermometer shows 653 to 732 °C for equilibrium of these two minerals Manuscript profile

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8 - Geochemistry of Salafchegan quartz diorite pluton
Mahbobeh Nazari Shahryar Keshtgar Ali Kananian Mohammad Boomeri

The Salafchegan quartz diorite pluton which is located at 45 km southwest of Qom, has intruded sandstone and sandy limestone of the Upper Red Formation as small subvolcanic intrusion. A zigzag pattern of major and trace elements variations in these intrusive rocks, from More

The Salafchegan quartz diorite pluton which is located at 45 km southwest of Qom, has intruded sandstone and sandy limestone of the Upper Red Formation as small subvolcanic intrusion. A zigzag pattern of major and trace elements variations in these intrusive rocks, from margin to the center of the pluton, may indicate periodical magma chamber refreshments. These subvolcanic rocks show geochemical calc-alkaline affinity and in the case of aluminum saturation index, they could be classified as meta-aluminous rocks, similar to I type granitoids. These rocks are enriched in LILE, and LREE but depleted in HREE. In addition, they show negative anomalies of Nb and Ti, low Ce/Pb, high Ba/La and Ba/Th ratios associated with high Al content. They illustrate porphyritic texture accompanied by inequilibrium phenocrysts such as zoned plagioclase or reaction rims surrounding hornblende crystals. Based on petrographical studies and geochemical analysis, it could be suggested that the parent magma of these subvolcanic rocks was related to a subduction zone and has emplaced in a magmatic arc. Manuscript profile

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9 - Mineralogy, Geochemistry and Alteration of Ore Minerals in Glojeh Epithermal Veins, North of Zanjan
Majid Ghasemi Siani Behzad Mehrabi Mohammad khanazizi

The polymetallic epithermal Glojeh ore deposit is located in the middle of the Tarom-Hashtjin metallogenic province in Alborz-Azarbayejan (western Alborz). It consists of four major epithermal veins, in the South Glojeh and the North Glojeh areas. Andesitic basalt and More

The polymetallic epithermal Glojeh ore deposit is located in the middle of the Tarom-Hashtjin metallogenic province in Alborz-Azarbayejan (western Alborz). It consists of four major epithermal veins, in the South Glojeh and the North Glojeh areas. Andesitic basalt and dacite are hosting the mineralization in the South Glojeh and the North Glojeh veins, respectively. The in Glojeh area rocks include intrusive rocks (granodiorite, granite and quartzmonzonite), diabasitic dikes, and volcanic rocks (dacite, rhyolite, andesitic basalt and tuff). Based on genetic and crossed relations of vein and vienlets, mineralization in the Glojeh occurs in three stages: (1) early stage of Cu-Au-As-Sb-Fe-bearing minerals; (2) mid stage of Pb-Zn-Cu-Cd-Ag-bearing minerals and (3) late stage of hematite-goethite-Ag-Bi-Au-Pb minerals. Mineralogy and minerals chemistry studies show that galena in stage 2 (substage 2B) have inclusions of silver bearing minerals. Important silver bearing minerals in Glojeh veins are argentite, native silver, Ag-tetrahedrite, polybasite, matildite and marrite. Gold mineralization occured in substage 1B (stage 1), and is associated with specular hematite (specularite) as native gold and in substage 3A (stage 3) as inclusions of native gold and eletrum in hematite and quartz. Alteration in Glojeh district consists of propylilitization, argillization, sericitization and silicification, that have well-developed and zoned in the around Glojeh veins and extends ≈ 30 meters into the host rocks. Chlorite geothermometry in argillic zone (stage 2) and propylitic zone (stage 3) are 275°C and 200°C, respectively. Mass balance calculations indicate that Al, Zr, Ti, Y, Nb, and HREE were immobile elements during alteration. Manuscript profile

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10 - Petrology, geochemistry and ore potential of the Samen granitoid (SW Malayer, Hamedan)
Hassan Zamanian Farhad Ahmadnejad Akram Krami Taghipour

The Samen granitoid is located along the northwestern part of the Sanandaj- Sirjan Zone in the Southwestern of Malayer. Based on mineralogical and geochemical characteristics, five main facies have been recognized in the Samen granitoid which included granodiorite, monz More

The Samen granitoid is located along the northwestern part of the Sanandaj- Sirjan Zone in the Southwestern of Malayer. Based on mineralogical and geochemical characteristics, five main facies have been recognized in the Samen granitoid which included granodiorite, monzogranite, syenogranite, alkali-feldspar granite and quartz-monzonite. Granodiorite is the main facies of the pluton and is more wide spread than other facies. Geochemistry of major elements indicates that the Samen granitoid is metalomious (ACNK=0.75) to peralomious (ACNK=1.21) and is classified as volcanic arc granites (VAG) related to active continental margins and petrochemically belongs to calc alkaline with high K rock series. Depletion in Nb, Zr, Hf, Y, Ti and HREE and enrichment in K, Rb, Cs, Th and LREE is consistent with an arc setting related to the subduction of Neo-Tethyan oceanic crust beneath the Sanandaj-Sirjan zone. The pluton has been contaminated by interaction with upper crust. In the Samen district both calcic exoskarn (grossular-andradite/augite-diopside) and endoskarn (tremolite-actinolite/epidote) occur along the contacts between granitoid and marble. The present study indicates that geochemical characteristics of the granodiorite and quartz-monzonite Samen rocks are similar to the averages for Au-Cu- and Fe- skarns granitoids, whereas the geochemical characteristics of the monzogranite, syenogranite and alkali-feldspar granite are similar to averages for Sn- and Mo-skarn granitoids. Based on oxidizing conditions and magma evolution, the Samen granitoid is characterized by relatively unevolved to moderately evolved and oxidized suites, as in most Au-Cu core metal associations globally. Manuscript profile

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11 - Geochemistry and tectonic setting of Zargoli granodiorite in Sistan suture zone (South East Iran)
Shahryar Keshtgar Mohammad Boomeri Ali Kananian Mahbobeh Nazari

The Zargoli granodiorite is located in the northwest of Zahedan in Sistan suture zone. This granodiorite intruded a flysch-like unit at Oligocene and its SiO2 contents range from 62.4 to 66 wt. %. This gronodiorite is calc-alkaline, metaluminous and I-type. The Zargoli More

The Zargoli granodiorite is located in the northwest of Zahedan in Sistan suture zone. This granodiorite intruded a flysch-like unit at Oligocene and its SiO2 contents range from 62.4 to 66 wt. %. This gronodiorite is calc-alkaline, metaluminous and I-type. The Zargoli granodiorite shows negative anomaly of Ta, Ti, Nb, Eu and positive anomaly of Rb, Ce, La, Ba, Sr in spider diagrams suggesting that these rocks have been derived from the partial melting of lower crust. This magma was contaminated with flysh- type sediments during emplacement in Sistan suture zone. Discriminative diagrams indicate a volcanic arc (VAG) and active continental margin (ACM) tectono-magmatic setting for this pluton. Manuscript profile

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12 - Geochemistry of ore facies and alteration zoning pattern of the Varandan Ba-Pb-Cu volconogenic massive sulfide deposit, southwest of Qamsar
Fayegh Hashemi Fardin Mousivand Mahdi Rezaei-Kahkhaei

The Varandan Ba-Pb-Cu deposit is located in southwest of Qamsar which is part of Urumieh-Dokhtar magmatic-arc zone. Mineralozation occurred as four sub-horizons in the unit1 of volcaniclastics and volcanics (acidic tuff and andesite) of Middle-Late Eocene. Each sub-hori More

The Varandan Ba-Pb-Cu deposit is located in southwest of Qamsar which is part of Urumieh-Dokhtar magmatic-arc zone. Mineralozation occurred as four sub-horizons in the unit1 of volcaniclastics and volcanics (acidic tuff and andesite) of Middle-Late Eocene. Each sub-horizon consists of five ore facies including: 1) stringer zone, 2) vent complex zone, 3) massive zone, 4) bedded-banded zone and 5) hydrothermal-exhalative sediments of Fe and Mn bearing. Main wall rock alterations in the deposits include chloritic-quartz and quartz-sericitic. Alteration zoning is observed in the deposit as chloritic-quartz at the core and quartz-serisitic in the margins of the footwall of the ore sub-horizon. Electron microprob analysis (EPMA) on the chlorite in stringer zones of the second and third sub-horizons show that these chlorites are Fe-rich chlorite and close to the clinochlor field. Geochemical studies indicate that grades of Ag, As, Cu, Sb and Sr in the stratiform ore (bedded-banded and massive) of the third sub-horizon are much higher than the other sub-horizons, and are 41, 273, 1945, 390 and 1013 ppm, respectively. All geochemical studies show that metal zoning in this deposit is clear, this is characteristic of VMS deposits. Development of zone-refining and over refining processes caused leaching of Cu from the stringer zone and vent complex facies and its later precipitation in the bedded ore facies. Among across to different sub-horizons in the Varandan deposit, third sub-horizon is recognized as economic for Ag extraction . Manuscript profile

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13 - The Study of geochemical behavior of major and rare earth elements of garnet in the Darreh Vali pegmatites (North-east Boroujerd, Sanandaj-Sirjan zone)
Somaye Rahmani Zahra Tahmasbi Xin Ding Ahmad Ahmadi Khalagi

The pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quar More

The pegmatites of Darreh Vali region is located in the north-east of Boroujerd which is a part of Sanandaj-Sirjan zone. In the Darreh Vali area, granodiorite bodies are cut by small pegmatitic dykes with NW–SE trend. The mineralogy of studied pegmatites consists of quartz, alkali-feldspar (orthoclase and microcline), plagioclase, muscovite, garnet (almandine-spessartin), andalusite, tourmaline, and apatite. Chondrite-normalized patterns of the Darreh Vali pegmatite are characterized by low enrichments of LREE relative to HREE (LaN/YbN=1.76-4.04), with a relatively flat HREE distribution, and a strong negative Eu anomaly (Eu/Eu* =0.20-0.54). Major element chemistry of garnets in these pegmatites indicates a compositional zoning with decreasing MnO and increasing FeO from core towards the rim. In the case of the Darreh Vali pegmatites, all garnet crystals contain low CaO (0.15 to 0.29 wt.%) and high MnO (10.27 to 13.18 wt.%), which are similar to magmatic garnets from pegmatitic melts. On the MnO+CaO versus FeO+MgO (in wt. %) diagram, the composition of garnets shows that they probably crystallised in contact zones of pegmatite vein and from less evolved melts. LA-ICP-MS analyses show that analysed garnets have a high HREE, low LREE contents, and strong negative Eu anomaly (Eu/Eu*=0-0.41) in the core along with positive Eu anomaly (Eu/Eu*=0-3.22) at the rim. Y, HREE, Ti, Zr, Nb, Ta, Hf, U and Mn decrease from core to rim. These core-to-rim elemental variations are attributed to increasing fluid-phase and H2O activity in magma, along with increasing magma fractionation. REE patterns and Eu anomalies in zoned garnets suggest that they probably formed in reducing to oxidizing conditions. Manuscript profile

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14 - Hybrid fuzzy c-means clustering algorithm and multilayer perceptron for increasing the estimate accuracy of the geochemical element concentration case study: eastern zone of porphyry copper deposit of Sonajil
Moharam Jahangiri SeydReza Ghavami Behzad tokhmechi

Pattern recognition methods are able to identify the hidden relationships between exploration data, especially in the case of limited number of data. The geochemical distribution patterns of the elements are identified and generalized using these methods. Multilayer per More

Pattern recognition methods are able to identify the hidden relationships between exploration data, especially in the case of limited number of data. The geochemical distribution patterns of the elements are identified and generalized using these methods. Multilayer perceptron, MLP, is one of the pattern recognition methods which is used for the estimation of geochemical element concentrations in mineral deposit studies. In the current study, multilayer neural network was used to estimate the concentration of geochemical elements based on 1755 surface and borehole samples, analyzed by ICP. Fuzzy c-means, FCM, clustering algorithm was used to increase the neural network estimation accuracy. The optimal number of clusters in the dataset was identified by validation indices and was used to design estimator. The clustering data on average showed an increase of 13% accuracy compared to normal mode. The average accuracy was increased from 75 percent to 88 percent. Elements with the lowest estimation accuracy showed an acceptable increase on the estimation accuracy by using clustering data. Mean squared error was 0.079 using all data and decreased to 0.025 while using hybrid developed method. Manuscript profile

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15 - Clinopyroxene mineral chemistry of Peshtasar basalts, sedimentary basin of Moghan (NW Iran)
AbbasAli Amrei Reza Zarei Mohsen Moayyed Ahmad Ahmadi AmirMorteza Azimzadeh

With the east–west exposure trend, Peshtasar basalts are in the sedimentary basin of Moghan (Talesh structural zone), in the northwest of Iran.The Peshtasar complex lithologically includes basalt, andesitic basalt or basaltic andesite, megaporphyric andesite, leucite te More

With the east–west exposure trend, Peshtasar basalts are in the sedimentary basin of Moghan (Talesh structural zone), in the northwest of Iran.The Peshtasar complex lithologically includes basalt, andesitic basalt or basaltic andesite, megaporphyric andesite, leucite tephrite and volcanic breccia. The main constituent minerals are plagioclase, clinopyroxene, and iddingsitized olivine in basalts and plagioclase megacryst, clinopyroxene, and leucite in tephrite. The results of the microprobe analyses of clinopyroxene reveal the diopside composition. Clinopyroxenes of Peshtasar basalts have igneous nature originated from alkaline and continental magmatic serries. The results of termobarometry studies indicate the crystallization range from 800 -1200 degrees centigrade and crystallization pressure less than 5 kb. There was no water in composition of the parent magma of these rocks. The titanium contents of clinopyroxenes were low, indicating the presence of titano-magnetite (opaque minerals) in the rock. The ferric iron values in clinopyroxenes represents a high oxygen fugacity of magma. Manuscript profile

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16 - The main effective factors on the mineralization of Sonajil porphyry-epithermal copper-gold deposit, using remote sensing, mineralogical and geochemical studies
Mohammad Maanijou

In order to identify the main effective factors in the Sonajil Cu-Au porphyry-epithermal deposit, remote sensing, mineralogical and geochemical studies were carried on the deposit. After removing vegetation and topographic features by Normalized Difference Vegetation I More

In order to identify the main effective factors in the Sonajil Cu-Au porphyry-epithermal deposit, remote sensing, mineralogical and geochemical studies were carried on the deposit. After removing vegetation and topographic features by Normalized Difference Vegetation Index (NDVI), solar radiance, instrumental errors and albedo effects by Log Residual (LR), Band Ratio (BR), False Color Composite (FCC), Principal Component Analysis (PCA) and Mixture-Tuned Matched-Filtering (MTMF) were used to reveal main alteration zones of the study area. The phyllic, advanced argillic and propylitic altered rocks were identified and the results were validated by field and mineralogical studies. Also, geochemical data showed microdiorite, and shoshonite composition and also post-orogenic tectonic setting of the Sonajil porphyry-copper deposits. Eventually, the faulting density, composition, and the depth of mineralization were the affecting factors on the Sonajil deposit mineralization. Manuscript profile

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17 - The Study of mineral chemistry, tectonomagmatic setting and petrogenesis of plutonic bodies in Sursat Complex, NW Takab, Iran
Soraya Dadfar Farhad Aliani Ali Akbar Baharifar Mohamad Hossian Zarinkoub

The plutonic bodies occurring in Sursat complex are some parts of plutonic rocks of Sanandaj- Sirjan Zone. Based on the field observations and microscopic studies, rocks of the study area are consist of hornblende gabbro, quartz diorite, monzodiorite, granodiorite and t More

The plutonic bodies occurring in Sursat complex are some parts of plutonic rocks of Sanandaj- Sirjan Zone. Based on the field observations and microscopic studies, rocks of the study area are consist of hornblende gabbro, quartz diorite, monzodiorite, granodiorite and tonalite. The EPMA analyses of minerals such as amphiboles (in granodiorite and monzodiorite), plagioclases and alkali feldspars indicate that amphiboles are magnesiohornblende, plagioclases are albite and oligoclase and alkali feldspares are orthoclase. Geochemical studies indicate that monzodiorite unit (Turke Dare and Khangholi bodies) are metaluminous I-type and calc-alkaline in nature. They are plotted in volcanic arc granite (VAG) region with 87Sr/86Sr and εNd values equal to 0.70448 and -0.12. All evidence represent that the monzodiorite were generated from a magma which was derived from mantle affected by assimilation and contamination processes. Granodiorite unit (Pichaghci, Hamzeh Ghasem and Northeast Khangholi bodies) represents I-type, metaluminous to peraluminous and calc-alkaline characteristics and is plotted in VGA field of magmatic arc. The 87Sr/86Sr and εNd values are equal to 0.70529 and -2.82 respectively. So these granodiorites were generated through mixing processes of a mantle magma with crustal sources. Tonalite–trondhjemites group are I-type, tholeiitic, peraluminous according to the low value of Mg# (2.9-11.6), Cr (20-46 ppm) and Ni (1-2.4 ppm) contents. They are also low in LA/Yb, Sr/Y, and Nb/Ta. The slight negative anomaly in fractionated patterns of the rare earth elements (REE) and very low depletion in Eu, indicate that these rocks were resulted from amphibolitic crustal source that were previousely generated from thickened mafic crust or from basaltic plate in low pressures at shallow depth in the presence of abundant plagioclase. Manuscript profile

Open Access Article

18 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

19 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
Afshin Zohdi Hossein Kouhestani

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

20 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

21 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
Mahsa Noori

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

22 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

23 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
Afshin Zohdi Hossin Kohestani Ghsem Nabatian Mir Ali Asghar Mokhtari

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

24 - Geochemistry, and metamorphic evolution of the Sahib Az Zaman skarns and the related intrusion in East of Kerman
شهریار محمودی Salymah Dahgani Dashtabi

Sahib Az Zaman Mountain is located 8 km North East of the Kerman city. Study area is part of Central Iran structural zone and Orumiyeh Dokhtar volcanic arc. In this area several young intrusions with intermediate composition intruded into Cretaceous limestone. According More

Sahib Az Zaman Mountain is located 8 km North East of the Kerman city. Study area is part of Central Iran structural zone and Orumiyeh Dokhtar volcanic arc. In this area several young intrusions with intermediate composition intruded into Cretaceous limestone. According to stratigraphic evidence, these granitoids have Cenozoic age and produced thin skarnic halo. Based on mineralogical properties and whole rock geochemical analyses, Sahib Az Zaman skarn is a calc -silicate skarn. Based on this study, migration of silicon, magnesium, iron and trace elements from igneous intrusions towards calcareous host rock and the reverse migration of calcium and magnesium occurred from carbonate host rocks. Major minerals of igneous rocks include plagioclase, alkali feldspar, clinopyroxene, and amphibole. In the boundary of igneous rock body (endoskarn), monticellite is observed. In the skarns, garnet, clinopyroxene, idocrase, epidote and calcite are major minerals. Based on geochemical studies, garnets include grossular-andradite, clinopyroxenes are diopside and wollastonite is also present. Comparison of geochemical composition between skarns and igneous rocks, illustrated that emplacement of igneous body in the beginning, metasomatism affected the host rock fluids and after replacement and crystallization of the main intrusive body had the major role in providing fluids derived from the intrusive body. Manuscript profile

Open Access Article

25 - Study of original carbonate mineralogy of the Qom Formation using petrography and geochemical evidence in celestite ore section, Madabad, south of Zanjan
Afshin Zohdi Hossein Kohestani Ghasem Nabatian Mirali Mokhtari

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper More

The Qom Formation is the only hydrocarbon reservoir in the central Iran sedimentary basin. In most parts of the central Iran, the Qom Formation conformably overlies the Lower Red Formation with an erosional discontinuity and is in turn conformably overlain by the Upper Red Formation. In the Madabad celestite deposit (south of Zanjan), the Qom Formation is composed of 190 m of medium to thick-bedded and massive limestone, marly limestone and marl. Five main microfacies are identified in the limestone units of the Qom Formation in the Madabad area. These microfacies probably were deposited on a shelf carbonate platform. Petrographic studies suggest original calcite mineralogy for limestone units of the Qom Formation in the Madabad area. Geochemical studies (Ca, Mg, Na, Sr, Mn and Fe) also represent the original calcite mineralogy in a closed diagenetic system with low dissolution rates. These evidence show significant role of fractures rather than diagenetic processes such as dissolution for increasing the reservoir quality of the Qom Formation for the oil and gas fields (such as Serajeh and Alborz) of central Iran. Manuscript profile

Open Access Article

26 - Geochemistry, and metamorphic evolution of the Sahib Az Zaman skarns and the related intrusion in East of Kerman
شهریار محمودی Salime Dehghani

Sahib Az Zaman Mountain is located 8 km North East of the Kerman city. Study area is part of Central Iran structural zone and Orumiyeh Dokhtar volcanic arc. In this area several young intrusions with intermediate composition intruded into Cretaceous limestone. According More

Sahib Az Zaman Mountain is located 8 km North East of the Kerman city. Study area is part of Central Iran structural zone and Orumiyeh Dokhtar volcanic arc. In this area several young intrusions with intermediate composition intruded into Cretaceous limestone. According to stratigraphic evidence, these granitoids have Cenozoic age and produced thin skarnic halo. Based on mineralogical properties and whole rock geochemical analyses, Sahib Az Zaman skarn is a calc -silicate skarn. Based on this study, migration of silicon, magnesium, iron and trace elements from igneous intrusions towards calcareous host rock and the reverse migration of calcium and magnesium occurred from carbonate host rocks. Major minerals of igneous rocks include plagioclase, alkali feldspar, clinopyroxene, and amphibole. In the boundary of igneous rock body (endoskarn), monticellite is observed. In the skarns, garnet, clinopyroxene, idocrase, epidote and calcite are major minerals. Based on geochemical studies, garnets include grossular-andradite, clinopyroxenes are diopside and wollastonite is also present. Comparison of geochemical composition between skarns and igneous rocks, illustrated that emplacement of igneous body in the beginning, metasomatism affected the host rock fluids and after replacement and crystallization of the main intrusive body had the major role in providing fluids derived from the intrusive body. Manuscript profile

Open Access Article

27 - Occurrence of copper mineralization of Abgareh deposit based on geology, mineralogy and geochemical evidences, south of Damghan
Raziyeh Mahabady Mohammad Hassanpour sedghi

The Torud-Chah Shirin volcanic-sedimentary arc, in the south of Kavir-e-Chah Jam depression (SE of Damghan), hosted many Pb, Zn, Cu, Ag and Au occurrences and deposits. Abgareh copper deposit is located in the northeastern part. Field and petrographic studies indicate t More

The Torud-Chah Shirin volcanic-sedimentary arc, in the south of Kavir-e-Chah Jam depression (SE of Damghan), hosted many Pb, Zn, Cu, Ag and Au occurrences and deposits. Abgareh copper deposit is located in the northeastern part. Field and petrographic studies indicate that deposit area consist of andesite, basaltic andesite and basalt rocks and to a lesser extent crystal tuffs with a middle–upper Eocene age. The rocks are of high-K, calc-alkaline to shoshonitic in nature, and are formed in a magmatic arc setting in a subduction zone. According to the field observations and mineralogical studies, the mineralization in the region occurred in two stages: hypogene and supergene and weathering. Hypogen zone minerals are generally pyrite, chalcopyrite and bornite, while chalcocite, covellite, malachite and chrysocolla are considered as the main minerals in the supergene zone. Fractures resulting from faults in the rocks of the region created a favorable location for the influence of hydrothermal solution and it is considered as the main controller of mineralization. Most of the textures observed in the mineralization include vein-veinlets, open space filling, radial, replacement and disseminated forms. Geochemical studies indicate that copper has the most relative correlation with silver. Since silver has not been found as an independent crystalline phase, therefore copper was replaced by silver in chalcopyrite and chalcocite. Compared with chondrite and primitive mantle normalizing diagrams, the studied rocks show significant enrichment with respect to LREE and LILE and depletion in HREE and HFSE and negative anomalies in Ti and Nb elements. Based on the relevant diagrams, differential crystallization of mantle rocks had the essential role in the evolution of the studied rocks which were probably derived from enriched mantle. Based on petrography, structural control of mineralization, alteration type and its extention and simple mineralogy, it can be concluded that mineralization at Abgareh district has characteristics of an individual mineralization system. This system is related to evolution of hydrothermal fluid mineralization resulted in vein-type Cu mineralization. Manuscript profile

Open Access Article

28 - The effect of precipitation and lithology on hydrochemical characteristics of the Karstic Springs in North Khorasan Province
Fatemeh Bagheri Gholamhossein karami rahim bagheri Javad Meshkini

Karstic aquifers are vital water resources which are used for irrigation and drinking purposes in arid and semi-arid regions. Understanding of the hydrogeological behavior of these springs and the qualitative tracing of these water resources are the first step in their More

Karstic aquifers are vital water resources which are used for irrigation and drinking purposes in arid and semi-arid regions. Understanding of the hydrogeological behavior of these springs and the qualitative tracing of these water resources are the first step in their better management. There are wide outcrops of Tirgan karstic formation in the study area, in the north of Khorasan province. In this area, there are a few karstic springs the discharge rate ranges from 50 to 500 lit/s. The recharge area characteristics of these springs vary significantly with their elevation, catchment size, thickness of epikarst and degree of karstification. In this study, temporal and spatial hydrogeochemcal variations of the five karstic springs including Arnaveh, Rezghaneh, Estarkhi, Ghordanlo and Sarani and 3 rain stations are investigated during one year period. The effects of both precipitation and lithology on the chemistry of these karstic springs are also considered. The dominant rain water types are Ca-SO4-Cl and Ca-HCO3 which change into Ca-Mg- HCO3 type during ground water flow in karstic system. This karstic aquifer is recharged during winter snowfall. The EC values of the rainfall vary from 70 µmohs/cm in Namanloo station to 100 and 150 µmohs/cm in Estarkhi and Ghale Barbar stations, respectively. The summer precipitations have more EC value than winter precipitations. This is due to long trajectory of air masses through arid regions with dust particles. The time series variations of discharge value are negligible in some karstic springs except for Sarani and Estarkhi springs. Hydrochemical composition of Sarani, Ghordanlo and Estarkhi springs are mostly affected by precipitation; while, Arnaveh and Rezghaneh springs with the same precipitation composition in this area have higher EC values. This is due to soil cover in catchment area, dissolution of clay minerals and diffusion. Manuscript profile

Open Access Article

29 - Structural controls on the hydrogeochemistry of Azarshahr travertine springs, NW Iran
Karim Taghipour Mohammad Mahdi Khatib Mahmod Rez Heyhata Abdol Rez Vaezihir Esmail Shabanian

Travertine deposits in Azarshahr, NW Iran, are one of the most extensive travertine deposits in the world. The process of travertine deposit is currently active in the several springs. It was used a multidisciplinary approach to determine the source of fluids and struct More

Travertine deposits in Azarshahr, NW Iran, are one of the most extensive travertine deposits in the world. The process of travertine deposit is currently active in the several springs. It was used a multidisciplinary approach to determine the source of fluids and structural characteristics of travertine springs. Results of in-situ measurements and type of travertine deposits, demonstrate that the springs are of thermogenic type with hydrothermal sources. Hydrogeochemical diagrams and ionic ratios represent that the type of spring waters are calcium carbonate, with increased sodium and chloride ions levels due to mixing with brine waters. Geophysical studies showed that these brines originated from the Urmia Lake or related brines, which are intruded through fracture systems to relay zones of faults and mixed with hydrothermal bicarbonate-saturated fluids. This phenomenon shows that hydrochemistry of travertine springs are affected by Urmia Lake or related brines. Manuscript profile

Open Access Article

30 - Biotite mineral chemistry, geothermobarometry and the role of total Al content of biotite in distinguishing of mineralization in the Touyeh- Darvar granitoid, SW of Damghan, Eastern Alborz.
Azin Naderi Habibolah Ghasemi Lamberini Papadopoulou

Touyeh- Darvar granitoid pluton is situated in the south of eastern Alborz zone (45Km SW of Damghan in Semnan province). This pluton has intruded into the late Paleozoic formations (including Barut and Lalun). Based on the field observations and petrographic studies, th More

Touyeh- Darvar granitoid pluton is situated in the south of eastern Alborz zone (45Km SW of Damghan in Semnan province). This pluton has intruded into the late Paleozoic formations (including Barut and Lalun). Based on the field observations and petrographic studies, the pluton is composed of monzonites, quartz monzonite and monzodiorite. In terms of mineralogy, the Touyeh- Darvar granitoid consists of plagioclase, orthoclase, quartz, ± hornblende and ±biotite. Accessory minerals consists of ilmenite, magnetite, zircon, apatite, titanite and pyrite. Sericite, epidote, calcite, and chlorite are considered as secondary phases. The iron-rich biotite is the most significant mafic mineral which are situated in the alkaline and anorogenic biotite fields. The total Al content of biotite in granitic rocks can be a useful indicator for distinguishing between mineralized and non-mineralized granitic rocks. The presence of mineral veins from oxides and hydroxides of iron and manganese, fluorite, barite, lead and zinc in the host rock of this pluton also confirms that the biotite composition is useful for mineralization potential study of this pluton. Applying the thermometry based on the Ti content of biotite and barometery based on total Al content of biotite resulted in calculating temperature ranges of 650–730°C and pressures lower than 1Kb for stopping the exchange and final equilibrium of this mineral in the pluton. Manuscript profile

Open Access Article

31 - Separation of geochemical anomalies from the background by using concentration-number fractal methods in the Veshnavah Area (South of Qom)
Zahra Mohammadi Asl Abdollah Saidi Mehran Aryan Ali Solgi Taher Farhadinejud

20.1001.1.17357128.1399.14.53.2.9

In this study, the concentration-number fractal method was used for regional exploration studies, and determining the anomalies of copper, lead and zinc elements. For this purpose, 800 samples of stream sediments were selected from the rivers in the area (i.e. from Kaha More

In this study, the concentration-number fractal method was used for regional exploration studies, and determining the anomalies of copper, lead and zinc elements. For this purpose, 800 samples of stream sediments were selected from the rivers in the area (i.e. from Kahak and Aran geological maps, 1: 100,000 sheets) and then the anomalies of these elements were mapped. The results show that strong copper anomalies are observed in the northern, central, southern and western parts of the area and the highest lead anomalies are located in the western part of the area. Strong anomalies of the zinc element are located in the central, southern and western parts of the region. These anomalies coincide with the lithological units of andesitic- basalt lava, volcanic breccia, tuffs, dacites, small scale masses of quartz -diorite, and small-scale masses of quartz-monzonite. The obtained map from combining anomalies and faults map reveals that the anomalies are mostly concentrated in fault zones and fault intersection points in the area and faults play a fundamental role in ore mineralization. Manuscript profile

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32 - The study of geochemical behavior of major and rare earth elements of garnet in the metamorphic rocks at Boroujerd area (Sanandaj-Sirjan Zone)
فرشته سجادی Somaye Rahmani NASIM Shamsaddini Zahra Tahmasbi Hashemi Xink Ding Ahmad Ahmadi Khalagi

Garnet–mica schist and hornfels rock units are exposed in the east and southeast of Boroujerd. These rocks consist primarily of quartz, K-feldspar, plagioclase, garnet (almandine–spessartine), chlorite, cordierite, andalusite, sillimanite, biotite, muscovite, and minor More

Garnet–mica schist and hornfels rock units are exposed in the east and southeast of Boroujerd. These rocks consist primarily of quartz, K-feldspar, plagioclase, garnet (almandine–spessartine), chlorite, cordierite, andalusite, sillimanite, biotite, muscovite, and minor amounts of apatite, iron oxides (ilmenite and magnetite), and zircon. Whole-rock geochemical analyses reveal that the dominant protoliths are pelitic rocks. Major and trace element compositions suggest that the Boroujerd pelites were deposited along an active continental margin. Garnet porphryblasts in some hornfels samples are compositionally homogeneous with respect to major, trace and rare earth elements; this is attributed to the diffusional re-equilibration at high temperatures (>600 ºC). Garnet in schists and some hornfels samples show reverse compositional zoning with increasing Mn and decreasing Fe and Mg from core to rim. Higher concentrations of Mn in garnet rims are attributed to resorption during retrogression. The presence of chlorite around garnet porphryblasts in these schists also supports resorption during retrogression. In schists, concentrations of HREE and Y in garnet decrease from core to rim. These zoning patterns are interpreted to record garnet growth in a closed system (i.e., Rayleigh fractionation of compatible elements). Core–rim variations in the concentrations of trace elements and rare earth elements in garnet in the hornfels samples is negligible. The lack of prominent zoning of these elements in garnet from hornfels is interpreted as minimal fractionation due to rapid garnet growth. Manuscript profile

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33 - Study of mineral chemistry, geothermobarometry and tectonic setting of gabbroic rocks from north-west Hamedan, Iran
عادل ساکی Hooshang Pourkaseb Alireza Zarasvandi Milad Jahani Maryam Dorani

The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and More

The study area is geologically located in the northern area of the Sanandaj-Sirjan metamorphic zone. Based on petrographic study, the main minerals consists of plagioclase, pyroxene, amphibole and biotite and the accessory minerals are chlorite, muscovite, ilmenite and zircon. The obtained results from the mineral chemistry in this study indicate that the amphiboles are calcic amphiboles, and in terms of chemical composition they can be called pargasit, tschermakite and magnesiohomblende. Plagioclases are also andesian. Due to the low Na2O content, it can be concluded, that tectonically these amphiboles are of S-Amph type and are related to the subduction zones. Based on the high levels of Al2O3, the origin of amphiboles is mantle-type. Therefore, due to the ratio of Fetot (Fetot + Mg+2) to AlIv, which is less than 0.6, the oxygen fugacity was high. On the other hand, the water levels vary from 2 to 2.3 for hornblende crystallization. Different methods were used to perform thermobarometry, the best of which showed that the formation temperature of gabbroic mass has been in the range of 700°C (in average) and a pressure of 4.45- 7.52 Kb. According to the estimated pressures, the magma was originated at a depth of 25-30 Km, which is near the Moho discontinuity. Manuscript profile

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34 - Mineral chemistry and thermodynamics conditions of impure marbles formation from Neybaghi metamorphic complex, NE of Myaneh, Iran
Javad Izadyar

A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textura More

A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textural and mineralogical evidences, revealed two metamorphic stages. The early stage is testified by the minerals such as pyroxene (diopside), epidote (clinozoisite), amphibole 1 (edenite-pargasite) and plagioclase 1. The main stage have chlorite (clinochlore), phlogopite, amphibole 2 (tremolite) and plagioclase 2. P-T-XCO2 have been estimated for the early and main stage of metamorphism by computing nonideal and asymmetrical fugacity and activity and programing in THERMOCALC software for fluid and solid phases. The estimations give pressure, temperature and XCO2 of 9.5Kbar, 660°C and 0.35, whereas the main stage has been constrained at P=4.2Kbar, T=510°C, XCO2=0.4. The obtained P-T path shows that the Neybaghi marbles were formed under medium pressure condition and overprinted by a low pressure metamorphism. This type of P-T trend can be formed in collisional tectonic regime. Manuscript profile

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35 - Mineral chemistry and thermodynamics conditions of impure marbles formation from Neybaghi metamorphic complex, NE of Myaneh, Iran
Javad Izadyar Masumeh Sohrabi Aliasghar Sepahi Azar Gharloghi Leila Mohamadi

20.1001.1.17357128.1399.14.54.2.1

A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textura More

A metamorphic rock complex consists of slate, phyllite, micaschist and marble with NE – SW shistosity has cropped out in Neybaghi area in the NE of Myaneh. Impure marbles occur as thick and thin layers or massive bodies within the centeral area of this complex. Textural and mineralogical evidences, revealed two metamorphic stages. The early stage is testified by the minerals such as pyroxene (diopside), epidote (clinozoisite), amphibole 1 (edenite-pargasite) and plagioclase 1. The main stage have chlorite (clinochlore), phlogopite, amphibole 2 (tremolite) and plagioclase 2. P-T-XCO2 have been estimated for the early and main stage of metamorphism by computing nonideal and asymmetrical fugacity and activity and programing in THERMOCALC software for fluid and solid phases. The estimations give pressure, temperature and XCO2 of 9.5Kbar, 660°C and 0.35, whereas the main stage has been constrained at P=4.2Kbar, T=510°C, XCO2=0.4. The obtained P-T path shows that the Neybaghi marbles were formed under medium pressure condition and overprinted by a low pressure metamorphism. This type of P-T trend can be formed in collisional tectonic regime. Manuscript profile

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36 - Hydrogeochemistry of Gorganrood river in Gonbad-e-Kavoos district, Golestan province
Abbas Teimori گیتی فرقانی تهرانی Hadi Jabari Abdol Rez Kaboli

Rivers are the key resources for drinking and agricultural purposes and the assessment of water quality is very important. In this study, a detailed investigation has been made for identifying the natural and anthropogenic processes that offected the quality of Gorganro More

Rivers are the key resources for drinking and agricultural purposes and the assessment of water quality is very important. In this study, a detailed investigation has been made for identifying the natural and anthropogenic processes that offected the quality of Gorganrood and its tributaries water in the Gonbad-e-Kavoos district. The Gorganrood is the longest river in the Golestan province (NE of Iran). During previous years, various wastewaters (i.e. domestic, agricultural and industrial) produced in Gonbad-e-Kavoos district have been discharged into the Gorganrood. To evaluate the chemical quality of water in the study area, 37 water and 6 wastewater samples were collected. The physicochemical parameters including pH and EC were determined in situ by an EC/pH meters. The concentration of major ions was measured using the standard methods. The piper and Wilcox diagrams were used to assess the water type and water quality for irrigation, respectively. Scatter diagrams were used to assess the hydrochemical processes influencing the chemistry of the water samples. Results of this study indicate that the pH and EC values of the water samples decrease in the city district. This is due to the discharge of urban wastewaters with lower EC and pH values which leads to the dilution of the river water. The lower concentration of nitrate in water samples collected in the city district is probably due to the denitrification process. Results show that the prevailing water types of Gorganrood and its tributaries are Na-SO42- and Na-HCO3-, respectively. The entrance of tributaries enhances the Gorganrood water quality for drinking and agricultural puposes. Along the river course, the natural processes of halite- gypsum- anhydrite dissolution and ion exchange, as well as anthropogenic factors (discharge of agricultural and urban wastewaters) deteriorate the water quality. Manuscript profile

Open Access Article

37 - Mineralogy and mineral chemistry of Pb- Ag- (Zn-Cu-Ba) Ravanj mining district, North of Delijan
Majid Ghasemi siani Fateme Isaabadi

20.1001.1.17357128.1399.14.55.2.3

The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies con More

The Ravanj ore deposit in the North of Delijan formed in the sedimentary host rocks. This ore mineralization system is controlled by normal faults, and mineralization occurs as massive, laminate, open space fillings, breccia and hydrothermal vein/veinlets ore bodies consisting of galena, sphalerite, fahlore group minerals, pyrite, chalcopyrite, dolomite, calcite, ankerite, barite, and quartz. Sulfide ore mineralization occurred within two mineralization horizons consisting of the massive-breccia ore horizon hosted by massive upper limestone (Km2) and layered sulfide ore horizon in middle shale (Ks2) and lower thin bedded limestone (Km1) as syn-sedimentary to epigenetic mineralization. Dolomitization is the main alteration related to mineralization and occurs adjacent to normal fault and consists of diagenetic and two hydrothermal dolomites. Hydrothermal dolomites are rich in iron. The ankrite shows that the ore hydrothermal fluid was Fe-rich. Chemistry of galena II and sphalerite II show that these minerals have a tendency to tetrahedrite-tennantite side which are consistent with presence of fahlore mineral incluisions in the microscopic studies. High Cd content in sphalerite and the presence of acanthite show that fluid mineralization had low temperature. According to the evidence such as mineralogy, mineral chemistry, ore texture and structures, and structural studies and combining these results with geochemistry, fluid inclusion and isotope geochemistry, the Ravanj ore deposit can be considered as an Irish-type Zn- Pb deposit. Manuscript profile

Open Access Article

38 - Hydrochemical evaluation and qualitative deterioration assessment of Gorganrud River
Mojtaba G.Mahmoodlu Nader Jandaghi Maryam Sayadi

20.1001.1.17357128.1399.14.55.1.2

In this study, the hydrochemical evolution and qualitative deterioration of Gorganrud River water were investigated in a distance of approximately 100 km from the northern margin of the Alborz highlands to Gorgan Gulf. For this purpose, the analysis results of elven phy More

In this study, the hydrochemical evolution and qualitative deterioration of Gorganrud River water were investigated in a distance of approximately 100 km from the northern margin of the Alborz highlands to Gorgan Gulf. For this purpose, the analysis results of elven physicochemical parameters related to four hydrometric stations over a ten-year statistical period were used. Gibbs, Stiff, Piper, Durov diagrams as well as five saturation indices for carbonate, sulfate and chloride minerals were used to study the hydrochemical evolution of the river. Water quality changes in drinking (using Schoeller Diagram), agricultural (using Wilcox Diagram), and industrial (using corrosion indices) sectors along the Gorganrud River were also investigated. In this study, F test and hierarchical cluster analysis were used to analyze the variance of data and the number of factors affecting water hydrochemistry, respectively. The results showed that rock-water reaction, evaporation, and Gorgan Gulf saline water intrusion are the most important factors controlling the river water chemistry. Also, the water dominant type of Gorganrud River at the highlands margin is bicarbonate and as it enters the plain, it tends to reach full maturity, the type of sodium chloride. At all stations, river water is supersaturated with respect to calcite and dolomite but it is under saturated respect to anhydrite, gypsum and halite. However, evaporite minerals saturation increases in the flow direction. The quality of water for drinking and agriculture is suitable at the margins of highlands and as it enters the plain and the path to the Gorgan Gulf decreases sharply. According to the statistical analysis results, the most changes in physicochemical parameters are obtained between the Lazoure Station at the highlands margin and the Qazaghli Station in the middle part of the plain and after that no significant changes were observed between the quality parameters until Gorganroud outlet. Manuscript profile

Open Access Article

39 - Geochemistry and petrology of Qareh-Dash rhyolites from Shahindej- NW Iran: Geochemical features of post- collision volcanism
Masoumeh Ahangari معصومه نظری Mohsen Moazzen

20.1001.1.17357128.1399.14.56.4.7

Qareh-Dash rhyolites from the Shahindej area are peraluminous rocks with high SiO2 and K2O contents. These rocks are mainly composed of quartz, K- feldspar and rare plagioclase phenocrysts in a fine-grained K-feldspar rich matrix. Geochemically, Qareh-Dash rhyolites sho More

Qareh-Dash rhyolites from the Shahindej area are peraluminous rocks with high SiO2 and K2O contents. These rocks are mainly composed of quartz, K- feldspar and rare plagioclase phenocrysts in a fine-grained K-feldspar rich matrix. Geochemically, Qareh-Dash rhyolites show enrichment in LREEs and LILEs and depletion in HREEs. Field studies, textural and petrographical relations, along with whole rock geochemistry, demonstrate that the parental magma of the Qareh-Dash rhyolites was originated from the crust. The composition of the parental magma was modified due to fractional crystallization of plagioclase and titanomagnetite evidenced by negative Eu, Sr and Ti anomalies in multielement diagrams. The chemical characteristics of Qareh- Dash rhyolites such as Rb/Nb, K/Rb, Rb/Sr, Rb/Ba and Ga/Al ratios are similar to A-Type granites/ rhyolites associated with post- collision tectonic settings. According to Precambrian age for the Qareh-Dash rhyolites, formation of these rocks might be related to extensional phases which were probably taken place after closure of proto- Thetys Ocean. Manuscript profile

Open Access Article

40 - Assessment of mineralization potential using Stage factor analysis method (SFA) in Khoshnameh area, Hashjin, Ardabil province
Samira Hoseinpore Nejati Kamal Siahcheshm seyyed ghafour alavi pouya Zargari

20.1001.1.17357128.1400.15.57.8.0

The Khoshnameh altered area is located about 20 km south of Khalkhal (Ardebil province) and lies in the Hashjin metallogenic district. The formation of extensive serictic, argillic, silicic, chloritic and iron oxides alterations in the Chenar, Mahmudabad and east of Kho More

The Khoshnameh altered area is located about 20 km south of Khalkhal (Ardebil province) and lies in the Hashjin metallogenic district. The formation of extensive serictic, argillic, silicic, chloritic and iron oxides alterations in the Chenar, Mahmudabad and east of Khoshnameh, as well as the copper-lead-zinc mineralization events (e.g. Senjedeh, Shalvali and Ommabad) appears to be intimately affiliated to the fluids derived from upper Oligocene granodiorite intrusions which were emplaced within the Eocene trachy-basalt, andesite and pyroclastic rocks. The key point of this research is to investigate the preference of the Stage Factor Analysis (SFA) to evaluate the geochemical dispersion of mineralization and the visualization of real anomalies throughout the Khoshnameh area. Since the concentration of rock forming elements that are not related to mineralization has a negative effect on the factor privilege of elements, then the number of factors to increase the severity of anomalies must be reduce. For this purpose, initially nine factors were calculated based on the chemical composition of the samples. At this stage, non-representative elements and elements that did not participate in any of the factors were identified and removed from the data set and factor analysis was re-applied. After applying three stages of analysis on the data, the most effective predictive and important factors in terms of mineralization were deduced. Consequently, the number of factors decreased to 5. Therefore, using this method increases the prediction rate and success of the exploration, compared to the typical factor analysis method. Thus, the probable anomalies of Ba, Sn, Pb and Mo mineralization from the first factor and As, Cd and Sb mineralization from the fourth factor are predicted and introduced. Manuscript profile

Open Access Article

41 - Garmichay metapelites, NW Iran: whole rock chemistry, provenance and metamorphic conditions
Amir Mahamed Mohsen Moayyed Monir Modjarrad

20.1001.1.17357128.1400.15.57.4.6

The whole rock chemistry of the Garmichay metapelites located in the north of Miyaneh, NW Iran, is investigated to reveal the provenance and metamorphic conditions of the rocks. Petrofabric observations have revealed the syn-tectonic nature of regional metamorphic cordi More

The whole rock chemistry of the Garmichay metapelites located in the north of Miyaneh, NW Iran, is investigated to reveal the provenance and metamorphic conditions of the rocks. Petrofabric observations have revealed the syn-tectonic nature of regional metamorphic cordierite porphyroblasts in the metapelites. C' shear band structure is another feature that is observed in the rocks. Two regional metamorphic phases (RMP1, RMP2), one contact metamorphic phase (CMP) and two deformation (D1, D2) phases are identified. The major oxide geochemistry implies two sedimentary shale and greywacke parent rocks. Based on major, rare earth and trace elements (Ti, Ni, TiO2, Zr and K2O) the igneous source rock has been an andesite to dacite/rhyodacite. The CIA (chemical index of alteration) and CIW (chemical index of weathering) parameters imply a medium degree of alteration in the igneous source area. The Garmichay metapelites, in comparison with the PAAS and UCC, are enriched in Cs, La and Ce and depleted in Sr, Nb and Ta. The representative samples lie inside the paragenetic triangles of the compatibility diagrams that imply their thermodynamically stable conditions. Finally, based on the standard pseudosections, the maximum temperature and pressure range has been determined as 535-635 °C and 1-3 kb, respectively. Manuscript profile

Open Access Article

42 - Analysis of geochemical features of sabzevar dust, using Marble Dust Collector (MDCO)
آرش امینی بهنام شفیعی

20.1001.1.17357128.1401.16.63.1.2

Dust is one of the atmospheric phenomena that has adverse environmental effects and consequences. In order to study dusts in Sabzevar, samples were collected at the end of each season in 1390. In this research, sampling containers were installed in 16 locations on t More

Dust is one of the atmospheric phenomena that has adverse environmental effects and consequences. In order to study dusts in Sabzevar, samples were collected at the end of each season in 1390. In this research, sampling containers were installed in 16 locations on the roofs of houses and governmental offices based on the main and sub geographical directions and trapped samples in MDCO were measured by 0.0001 accuracy scale. For geochemical studies due to the volume of dust collected and the importance of the samples, basic oxides and trace elements of fine dust were measured using atomic absorption and ICP methods. Results has shown that the maximum dust volume were collected in the spring while the concentration of most polluting elements is higher in autumn. In terms of pollution, Cadmium and Zinc are of primary importance in sabzevar due to their very high pollution coefficient. Chromium and Nickle are of secondary importance with being in the range of moderate pollution and significant pollution coefficient. In the current situation, the pollution of elements such as copper, lead and arsenic in the dust of Sabzevar is not critical and worrying. Manuscript profile

Open Access Article

43 - Separation of geochemical anomalies of gold-copper by concentration -Number Fractal (C-N) method in southeast of Nain
B. Gholipour A. Kananian Sh. Niroomand A. Tarhani M. Fersowsi Rashed

20.1001.1.17357128.1401.16.61.1.8

In this paper, concentration-number fractal method was used to study regional exploration and geochemical anomaly separation; also anomalies of index elements including gold, arsenic, silver, copper, antimony, lead, zinc and molybdenum in the Qalehdar exploration area ( More

In this paper, concentration-number fractal method was used to study regional exploration and geochemical anomaly separation; also anomalies of index elements including gold, arsenic, silver, copper, antimony, lead, zinc and molybdenum in the Qalehdar exploration area (Isfahan province) was investigated. For this purpose, 336 samples of rock units were collected and analyzed by ICP-MS. Then the chemical analysis data were categorized and prepared after replacing the sensor data for processing..Using concentration-number fractal method, elemental anomalies in that area was identified and the anomalies were mapped. The results of geochemical studies in the area showed that different geochemical anomalies of Au, Mo, Cu, As, Sb, Pb, Zn are closely related to alteration zones and shallow plutons. These studies also led to the identification of a geochemical system.. After drawing the geochemical maps and identifying the anomalous regions, the anomalies of the various elements were correlated and a zoning was recognized. In this zoning from the center to the outside of the system,the anomalies respectively, include molybdenum (Mo), copper-molybdenum (Cu Mo), lead-zinc (Pb Zn) anomalies and finally the gold-arsenic anomaly (As Au) which is located at the periphery of the system. Manuscript profile

Open Access Article

44 - Mineral chemistry of clinopyroxene, an approach to petrogenesis of Saray Volcanic Complex–Northwest of Iran
M. Ghaderi N. Amel M. Moayyed

20.1001.1.17357128.1401.16.61.4.1

Saray volcano is an extinct volcano and is located in the east of Urmia Lake. This volcano mainly consists of Leucititic lava flows and their related pyroclastic materials forming a Sequence which repeated more than five times. Leucite phonolitic dykes, Lamprophyric (Mi More

Saray volcano is an extinct volcano and is located in the east of Urmia Lake. This volcano mainly consists of Leucititic lava flows and their related pyroclastic materials forming a Sequence which repeated more than five times. Leucite phonolitic dykes, Lamprophyric (Minette, Monchiquite and Spessartite) lavas and dykes, Trachytic domes and dykes, Syenitic dykes and a small syenitic stock are other rock types of Saray volcano. Since clinopyroxene is present in all rock types of this volcano, mineral chemistry study of clinopyroxenes in all rock types of Saray volcano, could help us to explain the relationship between different rock types. Clinopyroxenes of Saray volcano have diopside, salite and fassaite compositions. The majority of studied clinopyroxenes crystallize under 3-4 kb pressure and 1150 centigrade temperature. Tectono-magmatically speaking, these clinopyroxenes were mostly formed within plate basalts. Although the composition of rock types of Saray volcano is very different, almost constant composition of clinopyroxene in all rock types, show the same origin for all clinopyroxenes. However, it can be concluded that all rock types have the same origin. Manuscript profile

Open Access Article

45 - Karst geology of carbonate rocks mass in Abegarm area, south of Qazvin province
P. Armani M. Karimi M. Tajabadi

20.1001.1.17357128.1401.16.62.1.0

Understanding the geological phenomena created by dissolution can be a great help in understanding karst systems. Hence, geology is usually the first step in studying the karstification process. Abegarm is located in the Central Iran structural zone and includes the For More

Understanding the geological phenomena created by dissolution can be a great help in understanding karst systems. Hence, geology is usually the first step in studying the karstification process. Abegarm is located in the Central Iran structural zone and includes the Formations of the Paleozoic, Mesozoic and Cenozoic eras. The most important carbonate formations in Abegarm are Soltanieh, Ruteh, Elika, Lar and Qom formations. In this study, karstification potential was investigated after field work and sampling of carbonate rock units and comparing them in terms of the development of karst landforms. Sampling of karst springs in both dry and wet periods, as well as measurement of EC, pH and temperature on the ground were performed. Remote sensing studies were performed by ILWIS software on Landsat satellite images for isolation and calculation of the area of carbonate formations. AqQa software was used to review and interpret the findings of chemical analyses and Phree Qc software was used to model water chemistry. The most important karst landforms in the region include karrens, vugs, caves, and karst springs. Based on the combination of field studies and remote sensing data, the intensity of karstification in the Abegarm area graded from high to low, include: Qom, Soltanieh, Lar and Cretaceous formations. Based on karst development classification, Abegarm karstification is merokarst (incomplete) and shallow; and based on the karst cycle classification it is classified as juvenile to young. Manuscript profile

Open Access Article

46 - Mineralogy, geochemistry, and fluid inclusion characteristics of the Madanjoo skarn iron deposit, Sangan mining district, NE Iran
M. Fotovat Jami Masoud Alipour-Asll

20.1001.1.17357128.1401.16.62.3.2

The Madanjoo prospect is one of the eastern anomalies in the Sangan mining district. This area is located in the eastern part of the Cenozoic Alborz volcanic-plutonic arc. The geology of the area includes Jurassic shaly sandstone, lime mudstone, and sandstone, Upper Cre More

The Madanjoo prospect is one of the eastern anomalies in the Sangan mining district. This area is located in the eastern part of the Cenozoic Alborz volcanic-plutonic arc. The geology of the area includes Jurassic shaly sandstone, lime mudstone, and sandstone, Upper Cretaceous limestone and dolomitic limestone, and Upper Eocene tuff and lava flow sequences, Middle Eocene skarn rocks, and Quaternary sediments. The most important occurrence in the Madanjoo area is the penetration of ferrous fluids into terrigenous and carbonate formations, skarnization, and iron mineralization, which is characterized by the presence of magnetite and calcsilicates minerals. based on type and frequency of calcsilicates, The skarn zones include olivine-pyroxene-garnet skarn, garnet-pyroxene skarn, garnet skarn, pyroxene-wollastonite-magnetite skarn, magnetite skarn, phlogopite skarn, tremolite-actinolite skarn, and epidote skarn. Iron mineralization occurred as massive, banded, vein-veinlets, breccia, and disseminated forms mostly in the Upper Cretaceous limestone and dolomite rocks and along NE-SW fault zone trend. Magnetite is the main ore mineral accompanied with pyrite, chalcopyrite, pyrrhotite, and secondary iron minerals. The composition of the Madanjoo garnet, pyroxene, and olivine are andradite-grossular (mostly andradite), diopside-hedenbergite (mostly diopside), and forsterite, respectively. Thermobarometry study based on pyroxene chemistry show that pyroxenes crystallized in temperature range of 458-689 °C, pressure of 2.21 kb, and depth range of 1-2.5 km. Three main paragenetic stages of skarn formation and ore deposition were recognized in the Madanjoo deposit: (1) a prograde stage developed with prograde garnet and pyroxene forming at 330° to 410 °C with a fluid salinity between 33 to 58 wt.% NaCl equivalent, (2) a retrograde garnet, tremolite- actinolite, and calcite which formed at 120° to 300 °C with fluid salinity of 16 to 49 wt.% NaCl equivalent, and (3) a post-ore stage with calcite and minor quartz veins that developed at 95° to 190 °C with salinity range of 2 to 15 wt.% NaCl equivalent. Possible iron ore formation mechanisms include: fluid mixing, boiling, and dilution with meteoric waters along with decreasing temperature. Finally, the Madanjoo iron mineralization is introduced as a magnesian exoskarn iron deposit. Manuscript profile

Open Access Article

47 - Determination of formation temperature, oxygen fugacity and Ce4+/Ce3+ ratio with using zircon chemistry in the pegmatitic dikes of Malayer-Boroujerd-Shazand, Sanandaj-Sirjan zone
Majid Ghasemi siani

20.1001.1.17357128.1401.16.64.4.7

The Granitoid plutons in the Sanandaj-Sirjan zone host numerous pegmatitic dikes. This study is focused on mineral chemistry of zircons in the pegmatite dikes in the Malayer, Boroujerd and Shazand district to evaluate zircon crystallization temperature, oxygen fugacity More

The Granitoid plutons in the Sanandaj-Sirjan zone host numerous pegmatitic dikes. This study is focused on mineral chemistry of zircons in the pegmatite dikes in the Malayer, Boroujerd and Shazand district to evaluate zircon crystallization temperature, oxygen fugacity and Ce4+/Ce3+ ratio and also zircon/rock partition coefficients of REEs and U, Th, Ta, Nb and Y. Trace element discrimination digrams such as Th versus Y and Yb/Sm versus Y and Nb, indicated studied zircons were located in the syenite pegmatite field. Zircon/rock partition coefficients indicate that zircon granis are enriched in the HREE than LREE. Zircon chemistry show that zircon in the Shazand and Malayer pegmatite dikes have more Hf and less REE distribution than zircons in the Boroujerd pegmatite dikes. Consequently, it indicates the role of latter hydrothermal process in the formation of Boroujerd zircons. Crystallization temperature, oxygen fugacity and Ce4+/Ce3+ ratios decrease from Malayer to Shazand and finally Boroujerd pegmatite dikes. Reduced condition of magmatism, Th/U contents below 1 and Y/Ho content higher than 20 indicate that these pegmatities are barren. Manuscript profile

Open Access Article

48 - Extraction effect of deep and semi-deep wells on water table decline and groundwater qaulity parameters in Gorgan Plain
M. Pakdel M. G.Mahmoodlu N. Jandaghi A. Fathabadi Y. Nick Ghojogh

20.1001.1.17357128.1401.16.64.5.8

The present study was conducted to investigate the effect of increasing uncontrolled drilling of water wells and subsequent extraction of renewable capacity of Gorgan plain aquifer on the decrease in groundwater level and some water quality parameters in a specific peri More

The present study was conducted to investigate the effect of increasing uncontrolled drilling of water wells and subsequent extraction of renewable capacity of Gorgan plain aquifer on the decrease in groundwater level and some water quality parameters in a specific period of 30 years. For this purpose, the trend of rainfall changes, drilling wells, groundwater level fluctuations, as well as some physicochemical parameters were investigated in the studied period. Data analysis of variance was used to investigate the statistical differences between quantitative and qualitative parameters. The annual changes in drilling of authorized and illegal wells in the province shows an increasing trend in the number of wells drilled in the Gorgan plain, followed by an increase in the volume of water extracted since the early 1980s. The results of statistical studies, histograms of annual changes in groundwater level of deep and semi-deep wells as well as hydrographs of deep and semi-deep aquifers studied show a reduction in groundwater level in both semi-deep and deep aquifers in the study period. Since the average annual rainfall in the study period is almost constant, the drilling of shallow and deep wells followed by uncontrolled abstraction of deep and semi-deep aquifers is the most likely major factor in the decline of groundwater levels in the study plain. Based on the statistical results, a significant difference was observed between most of the physicochemical parameters of semi-deep and deep wells in the old and new periods. However, these changes are greater in semi-deep wells than the deep ones. Also, the two parameters Cl and Na, which are the main factors of water salinity, show the greatest changes. Hydrogeochemical diagrams of plain aquifers show an increase in soluble solids as well as changes in the type and hydrochemical facies of groundwater in the new period. However, the trend of changes in the shallow aquifer is more intense. Manuscript profile

Open Access Article

49 - Geochemistry and Mineral Chemistry of the Ahowan intrusion rocks, northeast Semnan (Central Iran)
Saeed Kamran Ahmad Ahmadi Khalaji M. Rezaei-Kahkhaei Zahra Tahmasbi

20.1001.1.17357128.1402.17.65.1.3

The study rocks outcropped in the northeast Semnan area. These rocks, composed of monzogabbro-monzodiorite, was intruded in the Eocene sedimentary and volcanic rocks. Plagioclase and clinopyroxene are the main constituent minerals of these rocks. The study rocks represe More

The study rocks outcropped in the northeast Semnan area. These rocks, composed of monzogabbro-monzodiorite, was intruded in the Eocene sedimentary and volcanic rocks. Plagioclase and clinopyroxene are the main constituent minerals of these rocks. The study rocks represent granular and poiiklitic textures. Based on EMPA data, clinopyroxenes, and plagioclases are diopside and augite and andesine, labradorite and bitonite in compositions and formed in temperatures ranged from 1104 to 1168 and less than 700 °C respectively. On the basis of tectonic discrimination diagrams, the investigated samples fall into volcanic arc domain resulted in subduction of Neothetian oceanic lithosphere beneath Central Iran block. Manuscript profile

Open Access Article

50 - Geology, Alteration, Geochemistry and Element distribution in Alteration Zones of Nughdoz- Zaylik Area, Arasbaran Magmatic Zone
M.R. Hosseinzadeh S. Maghfouri Mohsen Moayyed Z. Hadavi Chaharborj Nasir Amel

20.1001.1.17357128.1402.17.65.5.7

The study area is located in 25 km SE of Ahar and 40 km NW of Meshkin-Shahr around Naqadouz village. Hydrothermal alteration has resulted in the developing of Argillic, Argillic - Silicic, Silicic and propilitic zones in this area. Based on petrographic studies, the alt More

The study area is located in 25 km SE of Ahar and 40 km NW of Meshkin-Shahr around Naqadouz village. Hydrothermal alteration has resulted in the developing of Argillic, Argillic - Silicic, Silicic and propilitic zones in this area. Based on petrographic studies, the altered rocks are basaltic andesite, andesite, dacite, rhyolite and lithic tuff in composition, with porphyry, glomeroporphyry, hyalomicrolithic and microlithic porphyric textures. The XRD analysis of altered samples show cristobalite, natrilite, kaolinite, quartz, albite, sanidine and orthoclase as the main minerals. Geochemical studies indicate that the alteration fluid has hydrothermal source and supergene processes are more important than hypogene processes. In this study, we use the immobile element method to calculate mass-changes and trace elements transmission amount during hydrothermal alteration. The Eu/Eu* ratio is higher in altered samples than relatively unaltered samples and the ratio of Ce/Ce* is more than 1for the relatively unaltered and most altered samples. The ratio of (La/Yb) n indicated that the depletion of HREE in altered samples is more than LREE, and LREE enrichment can increase this ratio. The lower ratio of (Tb/Yb) n in altered than unaltered samples indicate less depletion of HREE relative to MREE. Considering the distribution pattern of REE’s in alteration zones, it seems that the behavior of elements are controlled by pH, T & P changes, Eh, preferred absorption by clayey and iron oxide minerals and ligands frequency including SO2-4 , PO4+3 , CI-, F-, CO2-3 . Manuscript profile

Open Access Article

51 - Mineralogy geochemistry and genesis of Kehdolan copper deposit Bostanabad east Azarbaijan
Alireza Yousefi Sh. Niroomand Abdorrahman Rajabi mohammad amini

Study area is located in Eastern Azerbaijan province, 27 km far from east Bostanabad, and the north of Qarehchaman geological map. According to field tracking and surveys, host rock of mineralization is a Subvolcanic rocks of Oligocene period. Based on microscopic studi More

Study area is located in Eastern Azerbaijan province, 27 km far from east Bostanabad, and the north of Qarehchaman geological map. According to field tracking and surveys, host rock of mineralization is a Subvolcanic rocks of Oligocene period. Based on microscopic studies, the most important of supergene part, containing primary oxide minerals (Magnetite), secondary oxide minerals (Malachite, Hematite and Goethite) and also sulphide minerals such as Chalcocite, Covellite, Pyrite and insignificance Chalcopyrite. Among the most important alterations, argillic, silicification, carbonization and propylithic can be noted. Geochemical studies shows that host rock of mineralization with Monzosyenitic composition, placed in high chalc-alkaline to shoshonitic and metaluminous range. Formation environment of host rock of mineralization is a volcanic arc of subduction zone that confirmed by normalized rare earth elements diagrams. Manuscript profile

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