Original Research Paper
Volume 23, Issue 90 , March 2014, Pages 1-1
Original Research Paper
Volume 23, Issue 90 , March 2014, Pages 2-2
Original Research Paper
Volume 23, Issue 90 , March 2014, Pages 3-3
Original Research Paper
S Veyseh; A Rajabi Khorrami
Abstract
The purpose of this paper is to analyze geological samples (water) using cartridge in order to pre- concentration of these samples. In this paper, the study of Uranium ion imprinted polymer (IIP) synthesis is addressed. The Uranium ion complex in (CH3Coo) 2 Uo2 .2H2O is considered as the initial nucleus ...
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The purpose of this paper is to analyze geological samples (water) using cartridge in order to pre- concentration of these samples. In this paper, the study of Uranium ion imprinted polymer (IIP) synthesis is addressed. The Uranium ion complex in (CH3Coo) 2 Uo2 .2H2O is considered as the initial nucleus of polymer. This complex is formed by di vinyl phosphonic acid (VIP) ligand. Then, ethylene glycol dimethacrylate (EGDMA) is used as cross linker and azobis isobutyronitril (AIBN) acting as initiator in polymerization is applied for the final synthesis of polymer. The synthesis of these polymers is performed by covalent interactions. The complex of non- imprinted polymer (NIP) is also synthesized under above- mentioned condition but without the presence of Uranium ion and ligand. IIP was obtained can be used as a high absorbent for solid phase extraction (IIP-SPE). In addition, the study of condition and tests such as pH effect on absorption, permeability factor, acid concentration and volume which is required for elution is conducted in order to test the column efficiency. The experimental evidences indicate that the maximum absorption of Uranium ion is in pH= 7. In addition, 1M nitric acid solution with 5 ml volume has the highest elution rate. The rate of uranium permeation was measured above 200 mm. The results were obtained by ICP-MS as reference and ICP-OES to promote the analytical reading and reduce the detection limit. These results indicate very high absorption of IIP for Uranium ions. It must be noted that this process was successfully applied for pre-concentration of geological samples, in particular water samples and led to the promotion of results from analyzing all metallic ions such as uranium ion in geological samples (water) by ICP-OES and analytical optimization with lower detection limit by ICP-MS.
Original Research Paper
F Mousivand; E Rastad; M.H Emami; J.M Peter
Abstract
Various types of volcanogenic massive sulfide (VMS) deposits occurred within the northern and southern parts of the Sanandaj-Sirjan zone (SSZ). The most important VMS deposits of the south SSZ includes the Bavanat Cu-Zn-Ag (pelitic mafic- or Besshi-type), Sargaz Cu-Zn (bimodal mafic- or Noranda-type), ...
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Various types of volcanogenic massive sulfide (VMS) deposits occurred within the northern and southern parts of the Sanandaj-Sirjan zone (SSZ). The most important VMS deposits of the south SSZ includes the Bavanat Cu-Zn-Ag (pelitic mafic- or Besshi-type), Sargaz Cu-Zn (bimodal mafic- or Noranda-type), and Chahgaz Zn-Pb-Cu (silicicalstic felsic-or Bathurst-type) deposits, and the north SSZ hosts the Barika gold-rich (bimodal felsic- or Kuroko-type) VMS deposit. Comparison of the VMS deposits, and investigating of possible relationship between formation of these deposits and tectono-magmatic processes within the SSZ indicate formation of all the deposits within intra-arc rift basins related to subduction of the Neo-Tethyan oceanic crust beneath the Iranian plate during Mesozoic period. Main reasons for formation of the different VMS types within the SSZ might be due to evolution of magma nature and intra-arc rift basins. Comparison between the deposits in many aspects including host and associated rock types and ore mineral paragenesis indicate clear differences between the Bavanat and Sargaz deposits and the Chahgaz deposit. It is inferred that the differences could be due to variations in magma compositions, i.e., felsic in the Chahgaz, and mafic in the Bavanat and Sargaz host sequences. Indeed, development of the intra-arc rifting was at early/nascent stage in the Bavanat and Sargaz regions and at mature stage in the Chahgaz area.The SSZ (particularly the southern part) due to hosting various VMS type deposits and involving the known largest and majority VMS deposits in Iran is the most attractive structural zone for VMS exploration.
Original Research Paper
Z Solaymani; N Taghipour; R Aharipour
Abstract
This study investigates the organic petrographic of the upper Triassic to Lower Jurassic Olang coal deposits. Olang area is located in 70 km of northeast Shahroud. This area is situated in Gheshlagh Olang synclinal which is a member of eastern Alborz coal basin. Microscopic studies showed that all three ...
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This study investigates the organic petrographic of the upper Triassic to Lower Jurassic Olang coal deposits. Olang area is located in 70 km of northeast Shahroud. This area is situated in Gheshlagh Olang synclinal which is a member of eastern Alborz coal basin. Microscopic studies showed that all three maceral groups of vitrinite, inertinite and liptinite presented in coal deposits of the Olang region and the vitrinite is most important maceral group in these coals. Macerals of vitrinite group include colotelinite, collodetrinite and corpogelinit that collodetrinite is the most abundant of maceral in coal deposits. All of inertinite macerals group observed in these coals which Semifusinite and fusinite are the most abundant in this group. Spornite, cutinite, resinite and lipthodetrinite macerals of liptinite group are present in the coals. Abundance of collodetrinite, presentation of fnginite and the absence of tellinite in these coals are usually thought to indicate deposition in neutral to weakly alkaline waters in an oxygen-rich environment.
Original Research Paper
F Doulati Ardejani; M Pishdadian; A.R Arab-Amiri; R Kakaei; M Mohammado Khorasani
Abstract
In the aim of petroleum exploration at Qum area, gravity and magnetic measurements incorporating 2059 measuring stations have been conducted in order to detect likely buried oil traps, any volcanic intrusive, faults and subsurface folding related to the Qum formation. Bouguer and total magnetic anomaly ...
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In the aim of petroleum exploration at Qum area, gravity and magnetic measurements incorporating 2059 measuring stations have been conducted in order to detect likely buried oil traps, any volcanic intrusive, faults and subsurface folding related to the Qum formation. Bouguer and total magnetic anomaly maps were produced when the required corrections were made on the gravity and magnet data. The fractal method incorporating intensity-area model was used to produce residual gravity and magnetic maps. These maps were compared with those maps produced by trend surface analytical method and then interpreted. The results obtained by the interpretation show that although the presence of an anticline which was determined using gravity method is important for petroleum exploration; however, the magnetic intensity is very high on a part of this anomaly. Furthermore, it is probably affected by the surrounding faults. The results obtained in this study can be effectively used to decide doing further exploration works in the study are.
Original Research Paper
M Roohafza; S Alipour; A Abedini
Abstract
Ghareh-bolagh area is located in 20 Km of east of Mahabad, south of West-Azarbaidjan province. Carbonate rocks of Bayandour formation and dolomites of Soltanieh formation in this area are the host of mineralizations from Barium, iron and manganese. Based upon mineralogical investigations, barite, magnetite, ...
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Ghareh-bolagh area is located in 20 Km of east of Mahabad, south of West-Azarbaidjan province. Carbonate rocks of Bayandour formation and dolomites of Soltanieh formation in this area are the host of mineralizations from Barium, iron and manganese. Based upon mineralogical investigations, barite, magnetite, hematite, goethite, limonite, pyrolusite were major mineral assemblages of these mineralizations which that is accompanied by chalcopyrite, malachite, azurite, and calcite in low amounts. The most important geochemical characteristic these mineralizations are relative weak differentiation of LREE from HREE in barite and iron-manganese ores, Eu negative anomalies in iron-manganese ores (0.26-0.76) and Eu positive anomalies in barite (7.7-10.51). Incorporation of the obtained results from investigations of field, petrographic and geochemical (analytic data and correlation coefficients between elements) indicate that factors such as changes in physicochemical conditions of environment (pH, Eh, temperature), activity of complexing ligands, and presence of minor mineral phases (clay minerals, zircon, zenotime, and monazite) played important role in distribution of rare earth elements during mineralization and development of these ores.
Original Research Paper
Z Sadeghi; M.J Valadanzouj; M Dehghani
Abstract
Temporal and geometrical decorrelation often prevents SAR conventional interferometry from being an operational tool for surface deformation monitoring. Persistent Scatterer Interferometry (PSI) techniques presented to overcome the limitation of SAR conventional interferometry and use ...
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Temporal and geometrical decorrelation often prevents SAR conventional interferometry from being an operational tool for surface deformation monitoring. Persistent Scatterer Interferometry (PSI) techniques presented to overcome the limitation of SAR conventional interferometry and use amplitude analysis and considering temporal deformation model for PS pixel selection fail to identify PS pixels in rural areas lacking man-made structures. On the other hand, the high subsidence rates lead to not be fulfilled the required condition for unwrapping (Nyquist sampling criterion) and significant phase unwrapping errors in novel PSI algorithm (StaMPS) that applies amplitude analysis as well as phase stability in order to select the PS pixels without using a pre-define deformation model. Therefore, in this paper we present an enhanced algorithm based on PSI in order to estimate deformation rate in rural area undergoing high and nearly constant deformation rate using the available SAR images. The proposed approach integrates the merits of all existing PSI algorithms in PS pixel selection and phase unwrapping. PS pixels are selected based on the amplitude information and phase stability and their phase are compensated for APS and nonlinear deformation contribution by applying temporal filter. Deformation rate is then estimated using LAMBDA method that is a fast and optimal without considering Niquist sampling criterion. The approach was applied to the ENVISAT ASAR images of Southwestern Tehran basin and the results were evaluated with leveling data and the maximum difference rate across the leveling stations was 5 cm/yr demonstrating the high performance of the proposed algorithm in comparison with the obtained results from other interferometry methods. Moreover, the presented algorithm was applied to the simulated data and the value of RMSE was obtained 0.003 m/yr confirming this success.
Original Research Paper
A Mohammadi; Gh.A Kazemi
Abstract
Shoghan plain is one of the sub-catchments of the central Kavir, in NorthKhorasanProvince which experiences semi-arid to arid climate. With the exception of its eastern part, the quality of water in Shoghan aquifer is very low, unacceptable even for agricultural use. One of the main factors that deteriorate ...
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Shoghan plain is one of the sub-catchments of the central Kavir, in NorthKhorasanProvince which experiences semi-arid to arid climate. With the exception of its eastern part, the quality of water in Shoghan aquifer is very low, unacceptable even for agricultural use. One of the main factors that deteriorate the quality of groundwater is local geology which comprises mostly sedimentary rocks and in particular evaporites. In order to study the effects of geological formations on the quality of groundwater, 31 water samples were collected from different parts of the aquifer in 2009 and were analyzed for acidity, electrical conductivity and major ions. In the second step, ion distribution maps were prepared and geological characteristics were rechecked in the field. There is a clear impact of geology on the distribution of ions. A combination of ions cross plots and saturation indices of gypsum, halite, calcite and dolomite minerals show that the dissolution of these minerals and weathering of silicate minerals is commonplace in the aquifer. Due to high concentrations of sodium in the groundwater of the area, reverse ion exchange is one of the chemical processes controlling the chemical composition of groundwater.
Original Research Paper
R Dabiri; M.H Emami; H Mollaei; M Ghaffari; M Vosougi Abedini; N Rashidnejad Omran
Abstract
Quaternary volcanic rocks are widely developed in NW of Ahar, NW Iran. Based on geochemical data, these rocks mainly consist of alkali basalts, trachybasalts, basaltic trachyandesites and trachyandesites. The major- and trace-element chemistry indicates that the lavas are dominantly alkaline in character. ...
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Quaternary volcanic rocks are widely developed in NW of Ahar, NW Iran. Based on geochemical data, these rocks mainly consist of alkali basalts, trachybasalts, basaltic trachyandesites and trachyandesites. The major- and trace-element chemistry indicates that the lavas are dominantly alkaline in character. The studied rocks display microlithic porphyritic texture with phenocrysts of olivine, clinopyroxene, and plagioclase ± amphibole ± biotite. Major and trace element abundances vary along continuous trends of increasing SiO2, Al2O3, K2O, Na2O, Ba and Rb decreasing CaO, Fe2O3* and Cr with decreasing MgO.The volcanic rocks in this area are characterized by the LILE and LREE enrichments and negative HFSE anomalies. The Sr and Nd isotopic ratios vary from 0.704463 to 0.704921and from 0.512649 to 0.512774, respectively.CaO/Al2O3 ratios versus MgO, La/Sm ratios versus Rb and Ba and Zr versus Th suggest that that fractional crystallization was a major process during the evolution of magmas. AFC modeling and isotopic data as well as microscopic evidence, clearly indicate that crustal contamination accompanied by the fractional crystallization played an important role in petrogenesis of the trachyandesites. Also, geochemical and isotopic compositions indicate that magma mixing was not essential process in the evolution of Ahar magmas. Alkali basaltswith high 143Nd/144Nd ratio, low 87Sr/86Sr ratio and high MgO, Ni and Cr contents indicate that they crystallized from relatively primitive magmas. REE modelling and Trace element ratios indicate that the alkali baslats were derived by small degrees (~1-3%) of partial melting from the spinel lherzolite.
Original Research Paper
M Foroutan; H Nazari; B Meyer; M Sébrier; M Fattahi; K Le Dortz; M Ghorashi; Kh Hessami; M. R Ghassemi; M Talebian
Abstract
The Dehshir fault system (DFS) including six fault segments forms the western border of NS-striking active dextral strike-slip fault cutting the Sanandaj-Sirjan, Uromieh-Dokhtar magmatic arc, and Central Iran. This active fault system right-laterally offset Eocene volcanic rocks and Quaternary alluvial ...
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The Dehshir fault system (DFS) including six fault segments forms the western border of NS-striking active dextral strike-slip fault cutting the Sanandaj-Sirjan, Uromieh-Dokhtar magmatic arc, and Central Iran. This active fault system right-laterally offset Eocene volcanic rocks and Quaternary alluvial fans. Geomorphic evidence imply the activity of the DFS in the Late Quaternary, and paleoseismic investigations revealed seismic movements along the Marvast fault segment during the Late Pleistocene and Holocene timescales. In order to unravel the seismic history of the DFS over the intermediate geologic (103 -105 yr) time scale, and based on the morphotectonics and sedimentary-stratigraphic properties, three paleoseismic sites have been selected along the 35-km-long stretch of the Marvast fault segment. The southern site (Harabarjan) shows steep fault branches of N140±10º strike with sub-horizontal striations in dextral component. Another trench has been excavated at the North Marvast site whitin the Late Pleistocene-Holocene alluvial and colluvial deposits. OSL analysis of loose quartz rich deposits yielded an age of ~72 ka for the oldest exposed sediments. Paleoseismic stduies along the Marvast fault segment provide evidence for the occurrence of several large seismic events associated with surface ruptures along the DFS. The chronology of paleoearthquakes on the Marvast segment indicates that at least 7 large (≈Mw > 7) earthquakes occurred in the last 43 ka with an average recurrence time of 3650±150 years. The most recent earthquake, event I, occurred ~2200 years ago, which associated with 2-4 m of dextral slip and >40 km surface rupture along the Marvast fault segment. These investigations are compatible with the lack of destruction in the Marvast historical (~1300 years) castle, located
Original Research Paper
A Naeimi; Gh Heidarzadeh; M.R Sheikholeslami
Abstract
Geomorphic evidence along the Siah kuh fault (North of Jajarm) shows this fault has been active during Quaternary. Faulted Quaternary deposits, deflected and offset streams and bisected alluvial fans are among such evidence. These together with fault scarps in Neogene and Quaternary strata reveal young ...
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Geomorphic evidence along the Siah kuh fault (North of Jajarm) shows this fault has been active during Quaternary. Faulted Quaternary deposits, deflected and offset streams and bisected alluvial fans are among such evidence. These together with fault scarps in Neogene and Quaternary strata reveal young left-lateral motions on the Siah kuh fault as a part of the Shahrud fault system. However, there are Paleozoic and Mesozoic Formations juxtaposed with Neogene and Quaternary deposits along the fault. Some of these old units have cropped out in northeastern termination and bends along the fault, while others are observed where there is not a bend. Therefore, thrust faulting must have brought them to the surface. Aeromagnetic maps show that Siah kuh fault coincides with an aeromagnetic lineament. Consequently, the geomorphic features suggest only the youngest slips on the fault. Therefore, the Siah Kuh has been a thrust fault whose kinematics change and initiation of left-lateral motions resulted from changes in stress regimes and a regional reorganization during Quaternary.
Original Research Paper
Gh Razaghian; A Beitollahi; M Pourkermani; M Arian
Abstract
Iran is in the middle part of the seismic belt of Alps-Himalayas with dissimilar geological, structural and seismological features. In the present article, zonation maps of the earthquake occurrence rate (Rate) and the largest observed earthquakes (Mmax) have been prepared for all the regions of Iran. ...
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Iran is in the middle part of the seismic belt of Alps-Himalayas with dissimilar geological, structural and seismological features. In the present article, zonation maps of the earthquake occurrence rate (Rate) and the largest observed earthquakes (Mmax) have been prepared for all the regions of Iran. The parameter (Rate) shows the number of occurred earthquakes in the year in the region of Iran. Subsequently, according to the zonations, classification of different regions with different seismic activities will be achievable. The zonation map of earthquake occurrence frequency (Rate) in the present article shows that trend of the main classified zonations, according to the calculations, is similar with the geological and structural features of the region. It seems that zonation of Zagros and certain parts of the east of Alborz and Kopedagh with the maximum rate of earthquakes are drastically different with the zonation of central parts of Iran, Makran and eastern part of Iran with low seismic activities. In addition to zonation maps of the earthquake occurrence rate, zonation of the largest observed earthquakes (Mmax) has been provided in this region as well. According to the map, different regions of the Central part of Iran and Alborz with large seismic activities are different with other regions of Iran. Having compared the two zonation maps in this article, it is possible to classify the seismic activities of different regions. The seismic data and the basis of the article are according to the National and International Seismology catalogue for a period of 1900 to 2008.
Original Research Paper
A Pireh; S.A Alavi; M.R Ghassemi; A Shaban
Abstract
A major part of source rocks in the Zagros Fold Belt were deposited during Neocomian time; the lowermost part of the Garau Formation has charged the Early Cretaceous Petroleum System of the Lurestan province. These source rocks are widely distributed in the Lurestan Depression and in the NW part of the ...
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A major part of source rocks in the Zagros Fold Belt were deposited during Neocomian time; the lowermost part of the Garau Formation has charged the Early Cretaceous Petroleum System of the Lurestan province. These source rocks are widely distributed in the Lurestan Depression and in the NW part of the Dezful Embayment. The Kabir-Kuh anticline, which is a prominent structure of the Lurestan province, is more than 200 km long, and contains outcrop of the Garau Formation. Natural fracture systems have an important role in increasing of permeability and sometimes porosity of many reservoirs, and are necessary for the primary migration of hydrocarbons from the source rock to the reservoir. We have collected and analyzed field data on fracture set densities andtypes in Garau Formation and in parts of Sarvak Formation which outcrop in the Kabir kuh anticline of Zagros Belt. According to our analyses we have identified 8 fracture sets in 4 fracture systems: 1) a NNE-SSW transverse fracture system (sets A and B), 2) an ESE-WNW longitudinal fracture system (sets C and D), 3) a NE-SW and NNW-SSE oblique fracture system (sets E and F), 4) a SE-NW and ENE-WSW oblique fracture system (sets G and H). The transverse fractures and their orthogonal stylolites are Early Cretaceous to pre-late Miocene in age, while longitudinal and oblique fracture systems have formed since Late Miocene. Some transverse fractures show calcite infillings. We suggest that there have been two phases of counterclockwise rotation in orientation of the stress fields that produced these fractures, 1) a counterclockwise rotation of the stress field between development of non-mineralized fractures and open fractures and 2) a counterclockwise rotation of the stress field between development of the oblique fracture system (sets E and F) and the extension fractures (sets A and B). These rotations in the stress field have probably occurred due to rotation of the Arabian plate during its convergence to the Eurasian plate.
Original Research Paper
Z Mohammadi asl; S Montazerolghaem
Abstract
The active faults upon which Tehran megacity was developed must be considered in urban planning. Insufficient preciseness and completeness of the previous fault maps and lack of required technical documentation for existing regulations on building construction in fault zones, prompted the Tehran disaster ...
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The active faults upon which Tehran megacity was developed must be considered in urban planning. Insufficient preciseness and completeness of the previous fault maps and lack of required technical documentation for existing regulations on building construction in fault zones, prompted the Tehran disaster mitigation and management organization (TDMMO) to scrutinize existing fault map and produce more accurate one and in the same time devise new regulations. To this end, the Alquist-Priolo (AP) Earthquake Fault Zoning Act and sets of Fault Evaluation Reports and Fault Investigation Reports of California were reviewed and necessary conclusions regarding eventual adoption of similar measures for Tehran were drawn.
Original Research Paper
M Delavari; S.A Amini; A Saccani
Abstract
Tertiary volcanism in east and northeast of Nehbandan, eastern Iran, includes mostly basic-intermediate associations. They are characterized by sodic (1<Na2O/K2O) compositions and contain both low-k tholeiitic and calk-alkaline series. Based on petrographic, mineral chemistry and whole-rock geochemical ...
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Tertiary volcanism in east and northeast of Nehbandan, eastern Iran, includes mostly basic-intermediate associations. They are characterized by sodic (1<Na2O/K2O) compositions and contain both low-k tholeiitic and calk-alkaline series. Based on petrographic, mineral chemistry and whole-rock geochemical evidences basalts can be classified into two groups; arc-related calc-alkaline basalts (CAB) and low-K tholeiites (LKT). The evolutionary trends of some major and trace elements vs. SiO2 and also chondrite-normalized rare earth element (REE) patterns represent gentic relation between low-K tholeiitic intermediates and LKT but reject calkalkaline intermediate generation by magmatic evolution from CAB. In MORB-normalized multi-element patterns, negative anomally of high field strength elements (HFSE) and enrichment of large-ion lithophile elements (LILE) suggest subduction zone-related tectonomagmatic setting for basic-intermediate associations in which compositional change from LKT to CAB is accompanied by the evolution of arc system. This scenario in Sistan suture zone is interpreted as subduction continuation of Sistan oceanic lithosphere in Tertiary.
Original Research Paper
M.A.A Mokhtari; H Moinvaziri2; M.R Ghorbani; M Mehrpartou
Abstract
Au-Cu-Mo mineralization of Aniq-Qarachilar area is located in Arasbaran ore zone within the Qaradagh batholith. Mineralization in this area mainly includes Au-Cu-Mo bearing quartz veins within the granodiorite that cropped out in three areas include: Qarachilar (2 major veins), Zarlidareh (8 veins) and ...
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Au-Cu-Mo mineralization of Aniq-Qarachilar area is located in Arasbaran ore zone within the Qaradagh batholith. Mineralization in this area mainly includes Au-Cu-Mo bearing quartz veins within the granodiorite that cropped out in three areas include: Qarachilar (2 major veins), Zarlidareh (8 veins) and Qaradareh (some narrow and short veins). Alterations around the quartz veins include sericitic and silisification that has limited development. Quartz veins have compact, boxwork and brecciated texture. Sheeted veins of quartz present in some areas especially in the Qarachilar area. Sulfide mineral content of these veins commonly less than 10 percent and includes pyrite, As- bearing pyrite, chalcopyrite, molybdenite, bornite, stibnite, sphalerite and galena. Secondary minerals include coveline, malachite, azurite and iron hydroxides. Geochemical studies and grades of elements indicate that Au, Ag, Cu and Mo have high content in quartz veins. The average grade for Au in two quartz veins in the Qarachilar area is 5.76 and 3.9 ppm. The average grade for Au in the quartz veins in the Zarlidareh area is 4.7, 3.12, 2.6, 0.45, 1.09, 1.34, 1.15 and 0.58 ppm. The highest Au grade is about 359 ppm that belongs to a quartz vein with boxwork texture in the Zarlidareh area (ZV1). Moreover, W and Bi have high concentration in some veins. There is a good correlation between Au and Ag, Mo, W and Bi. Au grades in the Qaradareh quartz veins is low, but Mo grades vary between 0.15- 1.15%. Mineralization as silisic sheeted veins within the granodioritic intrusion, low concentration of sulfide minerals within the quartz veins, limited alteration aureole, Au mineralization together with Mo mineralization and high concentrations of Bi and W and relatively good correlation of Au with Ag, Bi, W and Mo indicate that Au mineralization in the Aniq-Qarachilar area can be classified as an intrusion related gold systems.
Original Research Paper
A Gourabjeri; M.H Emami
Abstract
Gelmandeh Massive is located north-east of Saghand, in Yazd province. From tectonics point of view it belongs to Central Iran, the Kalmard_Posht-e-Badam Block. The metamorphic complex comprises amphibolites, marble, schist, quartz- feldspatic gneisses. The amphibolites are of three types. Namly: Hornblendite ...
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Gelmandeh Massive is located north-east of Saghand, in Yazd province. From tectonics point of view it belongs to Central Iran, the Kalmard_Posht-e-Badam Block. The metamorphic complex comprises amphibolites, marble, schist, quartz- feldspatic gneisses. The amphibolites are of three types. Namly: Hornblendite (composed of more than 90% hornblende), Garnet-amphibolites and amphibolitic gneiss. Deformations in Gelmandeh metamorphic complex are reflected in 6 types of rocks: 1-deformed igneous rocks, 2- mylonitic series rocks, 3-cataclastic series rocks, 4-regional metamorphic rocks, 5- mylonitic regional metamorphic, 6-cataclastic regional metamorphic rocks. Conspicuous deformational features comprise: tilted feldspars twining, erratic pertite, mirmecite, porphyroblasts, clasts with strain shadows, and strained & fish structure minerals showing right & left lateral sense.
Original Research Paper
S Hojati; H Khademi
Abstract
There is no information about the occurrence and characteristics of sepiolite deposits in Iran. Thus, to identify and characterize the physicochemical and mineralogical properties of Eliyato deposits in northeastern Iran, 10 samples from different locations were taken and studied by powder X-ray diffraction, ...
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There is no information about the occurrence and characteristics of sepiolite deposits in Iran. Thus, to identify and characterize the physicochemical and mineralogical properties of Eliyato deposits in northeastern Iran, 10 samples from different locations were taken and studied by powder X-ray diffraction, scanning and transmission electron microscopy, X-ray fluorescence, thermal analysis, infrared spectroscopy, specific surface area and cation exchange capacity. The results indicated that these deposits consist of well-crystallized sepiolite (70–80%), with minor amounts of quartz (10–20%) and dolomite (5–10%). The electron micrographs of the samples showed sepiolite as a long interwoven fibrous mat, pore-filling and coating material. This textural evidence suggests direct chemical precipitation of sepiolite from an Mg-rich solution and/or after the precipitation of dolomite. The chemical composition, determined by X-ray fluorescence, indicated a Mg-rich mineral with the structural formula (Si11.97Al0.03) (Mg7.20Al0.11Fe0.15) O30 (OH)4 (H2O)4.8H2O. This suggests low isomorphic substitutions of Al for Si and Mg in the tetrahedral and octahedral sheets of the mineral, respectively. In addition, thermal analysis indicated four endothermic reactions at 134, 336, 546 and 818 °C which are associated with the gradual elimination of adsorbed and zeolitic water from the mineral structure. The associated weight losses are 8.69, 3.31, 2.65 and 10.19%, respectively. The high surface area of the material, compared to that of the Vallecas sepiolite deposit in Spain, suggests its suitability for industrial applications.
Original Research Paper
D Dehnavi; S.R Moussavi-Harami; M.H Mahmudy Gharaie; F Ghaemi; F Ghaemi
Abstract
For understanding parent rocks, tectonics setting, paleoweathering condition and classification of Binalood’s Oligocene deposits, the petrography analysis was done, on samples from Damanjan and Baghshan-Gach sections, north of Neyshabour. 14 sandstones and 6 shale samples from both sections were ...
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For understanding parent rocks, tectonics setting, paleoweathering condition and classification of Binalood’s Oligocene deposits, the petrography analysis was done, on samples from Damanjan and Baghshan-Gach sections, north of Neyshabour. 14 sandstones and 6 shale samples from both sections were analyzed for major elements. Petrographic studies and geochemical data show that these sandstones are Litharenite to lithic arkose and have been deposited in tectonics setting including active continental margin for Damanjan section and continental island arc for Baghshan-Gach section with felsic to intermediate source. Based on elemental analysis, paleoweathering condition was relatively weak at the time of deposition in both sections; however, paleoweathering was stronger in Damanjan than Baghshan –Ghch sections. Also, using petrographic and elemental data, it can be concluded that the paleoclimate was semi-humid to semi-arid at the time of deposition.
Original Research Paper
H Kouhestani; M.H Ghaderi; M.H Emami; S Meffre; V Kamenetsky; J McPhie; Kh Zaw
Abstract
The Chah Zard Ag-Au deposit, a typical breccia-hosted low- to intermediate-sulfidation epithermal system, is located within late Miocene andesitic to rhyolitic volcanic complex in the central part of the Urumieh-Dokhtar magmatic belt. The orebodies are emplaced in breccia bodies dominantly hosted by ...
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The Chah Zard Ag-Au deposit, a typical breccia-hosted low- to intermediate-sulfidation epithermal system, is located within late Miocene andesitic to rhyolitic volcanic complex in the central part of the Urumieh-Dokhtar magmatic belt. The orebodies are emplaced in breccia bodies dominantly hosted by rhyolite porphyries. Systematic whole-rock geochemical investigations on the volcanic rocks show that both intermediate and felsic rocks are characterized by significant Large Ion Lithophile Elements (LILE) and Light Rare Earth Elements (LREE) enrichment coupled with High Field Strength Elements (HFSE) depletion. These geochemical data indicate subduction-related magmatic arc affinity for the volcanic rocks, and suggest that hornblende fractionation appears to be an important controlling factor on the evolution of mineralized subvolcanic rocks. Although the rhyolite porphyry has relatively high 87Sr/86Sr ratios, the volcanic rocks have similar Sr and Nd isotopic compositions, displaying 87Sr/86Sr range of 0.704910-0.705967 and εNd(i) values of +2.33 to +2.70. These data suggest that the rhyolitic magmas probably represent the final diffetentiates of parental andesitic magmas with minor crustal contamination. The andesitic magmas generated from partial melting of a mixture of an incompatible element depleted anhydrous asthenospheric mantle source and a hydrous LILE and LREE enriched lithospheric mantle source in response to slab-break-off and upwelling of asthenospheric mantle. The rhyolite porphyry is inferred to have supplied heat that drove the convective hydrothermal system at Chah Zard deposit, but also provided some of the fluid sources responsible for the development of the Chah Zard epithermal system.
Original Research Paper
Z Adeli; I Rassa; A Darvishzadeh
Abstract
The Haftcheshmeh Porphyry copper deposit is located 28km north of Varzaghan (East -Azerbayjan province). It is associated with quartzdioritic to granodioritic intrusive of Oligo- Miocene ages, which are intensively altered. The porphyritic bodies are intruded by a series of barren andesitic dykes. The ...
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The Haftcheshmeh Porphyry copper deposit is located 28km north of Varzaghan (East -Azerbayjan province). It is associated with quartzdioritic to granodioritic intrusive of Oligo- Miocene ages, which are intensively altered. The porphyritic bodies are intruded by a series of barren andesitic dykes. The principal aim of this paper is to consider the geochemistry and the origin of magma. Trends of major and trace elements indicate a continuous compositional range and a comagmatic origin for these rocks. However, trends of compatible-incompatible elements indicate the important role of fractional crystallization and contamination of the magma with upper crust in genesis of these rocks. Depletion in Ti, Nb and Sr and enrichment in K, Th and Rb are obvious in spider diagrams of these samples. The enrichment in LILE and depletion in HFSE reveal the I-type metaluminous magmatism of volcanic arcs (VAG). َAdditionally, the discrimination tectonic setting diagrams indicate I-type continental volcanic arc magmatism for this intrusion. The Microprobe analysis also confirms that the Biotite crystallized from typical calc-alkaline magma.
Original Research Paper
F Mohammadi; S Alipour; M Ghazanfari
Abstract
Gold as a strategic element has a strong exploration potential in KurdistanCounty. This investigation for gold has carried out in N.W. Sanandaj- Siirjan geological zone. 351 samples has been taken from drainages and analyzed by ICP-MS in Canada for 22 elements. Based on results, anomaly map and enrichment ...
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Gold as a strategic element has a strong exploration potential in KurdistanCounty. This investigation for gold has carried out in N.W. Sanandaj- Siirjan geological zone. 351 samples has been taken from drainages and analyzed by ICP-MS in Canada for 22 elements. Based on results, anomaly map and enrichment ratio for gold and related paragenetic elements have been prepared. The result indicate an enrichment factor of 1-99 times for gold and 1-3, 1-19, 1-3, 1-3, 1-6, 1-2, 1-7, and 1-4 for elements Ag, As, Pb, Zn, B, Ba, Bi and W, respectively. Data resulted to a distribution pattern for Au and other elements such as. Gold anomaly is recognize in 36 Km2 associated up to 19 times enrichment for As. Therefore As is a good indicator element for Au her and in similar environments. Tectonically gold showed a very strong relation with breccias zones and par genetic minerals.
Original Research Paper
Y Bayati-Rad; H Mirnejad; J Ghalamghash
Abstract
Gol-Gohar mining complex, located southwest of Sirjan (KermanProvince) and within the Sanandaj-Sirjan structural zone, has a number of iron-rich deposits that provides 30% of steel demand in the country. The main ore in this deposit is magnetite with subordinate amounts of hematite and accessory pyrite ...
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Gol-Gohar mining complex, located southwest of Sirjan (KermanProvince) and within the Sanandaj-Sirjan structural zone, has a number of iron-rich deposits that provides 30% of steel demand in the country. The main ore in this deposit is magnetite with subordinate amounts of hematite and accessory pyrite and chalcopyrite phases. Comparison of rare earth element (REE) distribution patterns of Gol-Gohar magnetite with those of magmatic magnetite (Kiruna) and also magnetite associated with granite and basalts show similar enrichment in light REE relative to the heavy REE and negative Eu anomaly. Such features can also be observed in apatite from Kiruna, Iron Spring, Choghar and Esfordi Fe ore deposits, the origin of all of which have been ascribed as magmatic due to a lack REE distribution patterns similar to phosphorites. Based on these characteristics, it seems that the magnetite in Gol-Gohar Fe deposit has dominantly originated from a magmatic fluid.
Original Research Paper
M.R Kebriaee- Zadeh
Abstract
Hojedk section is located 62 km north of Kerman. In this section Padeha Formation with Middle Devonian age overlies Bahram Formation conformably, and it is covered with Jamal Formation (Late Permian) with a disconformity boundary. The study of Bahram Formation brachiopoda resulting into 32 species and ...
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Hojedk section is located 62 km north of Kerman. In this section Padeha Formation with Middle Devonian age overlies Bahram Formation conformably, and it is covered with Jamal Formation (Late Permian) with a disconformity boundary. The study of Bahram Formation brachiopoda resulting into 32 species and subspecies consists of: Schizophoria striatula, Schizophoria cf. iowaensis, Devonoproductus sp., Productella cf. subaculeata, Strophodonta sp., Cyphoterorhynchus koraghensis, Cyphoterorhynchus koraghensis interpositus, Ripidiorhynchus elburzensis, Ripidiorhynchus kermanensis, Ripidiorhynchus minutissimus, Paropamisrhynchus kotalensis, Lateralatirostrum esfehensis, Spinatrypina chitralensis, Spinatrypina bodini, Spinatrypina cf. robusta , Desquamatia (Desquamatia) sp., Desquamatia (Serateypa) sp., Athyris chitralensis, Athyris sp., Anathyris e. g. helmersenii, Gypidula sp., Cyrtospirifer verneuili echinosus, Cyrtospirifer kermanensis, Cyrtospirifer schelonicus, Cyrtospirifer sp., Uchtospirifer multiplicatus, Uchtospirifer multiplicatus minor, Tenticospirifer cyrtinaformi, Tenticospirifer cf. tenticulum, Indospirifer sp., Rigauxia hutkensis, Cranaena cf. rigauxi, Based on the biostratigraphical value of the recognized brachiopoda, the age of Bahram Formation in the Hojedk section is determined Early- Late Frasnian.
Original Research Paper
H Azizi; H.R Siahkoohi; B Evans; N Keshavarz Frajkhah; E Kazemzadeh
Abstract
Rock physics is the major tool to describe physical property of reservoir rocks; such as porosity, permeability, degree of saturation, property fluid that saturated, shape of pores, compressibility and etc via studying ultrasonic wave transmitting through a rock sample.
Between these parameters, porosity ...
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Rock physics is the major tool to describe physical property of reservoir rocks; such as porosity, permeability, degree of saturation, property fluid that saturated, shape of pores, compressibility and etc via studying ultrasonic wave transmitting through a rock sample.
Between these parameters, porosity and degree of saturation are more effective on elastic wave velocities which have been studied extensively in recently years. Amplitude of acoustic waves is a function of acoustic impedances (velocity and density) could be used to study lithology, pore fluids and saturation. In this paper we studied how main characters wave (velocity, amplitude, frequency) changes related to two main reservoir characteristics (pore pressure and confining pressure). In our study, we transmitted ultrasonic waves in different frequencies through a sandstone core in reservoir pressure condition. Analysis confirmed that similar to previous studies, amplitude of transmitted signal is a more sensitive attribute to pressure changes rather than velocity of the waves.