Kh Baharfirouzi; A Khakzad; H Nazari; M.H Emami
Abstract
The Azerbaijan plateau is distinguished by varied geomorphology and mineralization, both of which controlled by the dominant structural regime in the area, that is associated with the collision of the Arabian and Eurasian plates. Strike slip faults are the main structural features controlling the development ...
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The Azerbaijan plateau is distinguished by varied geomorphology and mineralization, both of which controlled by the dominant structural regime in the area, that is associated with the collision of the Arabian and Eurasian plates. Strike slip faults are the main structural features controlling the development of various compressive or extensional zones in Azerbaijan. The dominant faults are striking NW-SE and NE-SW and display right lateral and left lateral displacements, respectively. The vergence of vectors on two sides of faults in the fault conjunctions, control the dominant stress regime, geomorphology, emplacement of dikes, as well as the gold-bearing silica veins. The bent parts and steps between different tips of faults are other controllers of dominated tectonic regime and emplacement of granitic stocks and gold bearing silica veins. Because of change on the strike of Ahar-Sarab fault, an extensional regime prevailed in southwest of Sabalan and silica veins injected in this area, some of these veins are auriferous.
SH Aboutorab; A Khakzad; F Gharib; S Mehdizadeh Tehrani
Abstract
The 1:100000 sheet of Ardestan is located in the south part of 1:250000 quadrangle of Kashan at 52º to 52º, 30 E and 33º to 33º, 30N in the north west of Isfahan province and Orumieh-Dokhtarvolcanic belt.Most of the rock units' ofArdestanregion include medium to basic volcanic ...
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The 1:100000 sheet of Ardestan is located in the south part of 1:250000 quadrangle of Kashan at 52º to 52º, 30 E and 33º to 33º, 30N in the north west of Isfahan province and Orumieh-Dokhtarvolcanic belt.Most of the rock units' ofArdestanregion include medium to basic volcanic and pyroclastic rocks, which are related to middle-upper Eocene volcanism phase. Intrusive rocks of this region have low-acidic to acidic combinations and belong to the shallow magmatism phase of Oligocene-Oligo Miocene and sub-volcanic activities of Pliocene. These intrusive rocks cause hydrothermal alteration and then mineralization of elements such as Cu, Mo, Au, Pb, Zn, and Fe. In this thesis, by employing the existing geological maps, systematic geochemical explorations, and known mineral indices together withthe derived information from processing of the existing airborne geophysics and satellite data (e.g. faults, hydrothermal alterations, total magnetic intensity and rock units), a number of different databases were formed.Then, by using the new weighted score method of analytic hierarchy process (AHP),these databases (also known as layers) are weighed based on the predicted genetic model of the region. These weighed layers are then modeled in the GIS system by using the index overlay method. Based on the achieved results from this study, promising area maps for Epithermal Gold is prepared.According to our field observations, sampling and laboratory analyses of the promising areas, 5areas with first priority are considered to have economical potentials and are introduced for the next phases of explorations.
T Nabaei; A Khakzad; M Hoseini; S.R Mehrnia
Abstract
The study area is a portion of Urmia-Bazman Magmatic Belt in the Central Iran Structural Zone that located in the south of Boein-Zahra city (Qazvin province). In this area, volcanic and pyroclastic rocks incised by a plutonic body and around and within this pluton, a large extensive alteration occurred. ...
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The study area is a portion of Urmia-Bazman Magmatic Belt in the Central Iran Structural Zone that located in the south of Boein-Zahra city (Qazvin province). In this area, volcanic and pyroclastic rocks incised by a plutonic body and around and within this pluton, a large extensive alteration occurred. In this study, Landsat 7 data (ETM+) employed and general alteration trend in the area was mapped by conventional methods of Color Composite (RGB), Band Rationing and specially Principal Components Analysis (PCA). All of the three methods are found to be effective for obtaining generalized information about the alteration of the image area. Principal Components Analysis (PCA) and especially Selective Principal Components Analysis (Crosta technique) found to be the best effective method in delineating the borders of clay and iron oxide altered areas. In the high altered wall rocks, mineralogical analysis results (XRD method) indicated two forms of vertical and horizontal zoning. In this case, in vertical zoning in order from down to up, advanced argillic, alunitic and silicified zones and in horizontal zoning from fault surface toward wallrocks, advanced argillic and propylitic zones were distinguished. The mineralogical composition of zones and form of zoning indicates that this type of alteration is "acid sulfate". The study of fluid inclusion of quartz crystals in silicic veins, indicated that liquid and vapor phases (LV) are present and study of them resulted in calculation of salinity percentages between 16.8 to 19.2 (NaCl wt%) and homogenization temperatures between 204oC to 280oC.
M Farmahini Farahani; A Khakzad; H Asadi Harooni; M.H Emami
Abstract
Kahang copper and molybdenum mine is located in Esfahan province and 10 Km far from the east of Zefreh town that is on Urumieh-Dokhtar volcanoplutonic belt. The Kahang region is an alteration and breccia zone. Generally, hydrothermal fluids have affected more than % 90 of rocks of this region. These ...
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Kahang copper and molybdenum mine is located in Esfahan province and 10 Km far from the east of Zefreh town that is on Urumieh-Dokhtar volcanoplutonic belt. The Kahang region is an alteration and breccia zone. Generally, hydrothermal fluids have affected more than % 90 of rocks of this region. These alteration are related to Copper (Cu) and Molybdenum (Mo) porphyry deposits. Most of the rocks are acidic, semi acidic and sub volcanic. Several kinds of alteration are observable in kahang as propylitic, argilic, silisification and phyllic. The basic oxides were highly decreased in dacite and rhyodacites of exploration area. This is an evidence of argilic alteration effect on the rock units considering that main deposit is not affected by erosion, placed in depth and potassic alteration is not exposed at surface. In study of existing alteration several methods such as remote sensing, studying of thin section and the chemical analysis of samples were used. Another issue that has taken into consideration in this paper is the magma mixing. This subject is confirmed by petrographic evidence such as sieve texture, corroded rims in primary phenocryst quartz, and hydrothermal effects on plagioclases especially in porphyritic andesites. Moreover, the extensive acidic rocks, notable alteration expanse, and also two generations of mineralization reveal assimilation in the studied area. This text has examined the similarities between Kahang and other porphyries in the Urumieh-Dokhtar zone.
M Khalajmasoumi; M Lotfi; A Memar Kuchebagh; A Khakzad; P Afzal
Abstract
The studied area in the Saghand fifth anomaly is located in the Bafgh-Posht-e-Badam metalogeny belt in the Central Iran zone. Uranium, Thorium and Rare Earth Elements mineralization are hydrothermal and metasomatism type related to area intrusion bodies (Granite and Gabbro available in the north of study ...
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The studied area in the Saghand fifth anomaly is located in the Bafgh-Posht-e-Badam metalogeny belt in the Central Iran zone. Uranium, Thorium and Rare Earth Elements mineralization are hydrothermal and metasomatism type related to area intrusion bodies (Granite and Gabbro available in the north of study area). Uranium of hydrothermal type followed by deep fracture systems and concentrated around the magnetite bodies. The reasons are geochemical environment and alkaline metasomatism of Uranium - Thorium and Rare Earth Elements produced under an important metalogeny cycle in the Central Iran and studied area. The tudied area in special case, Cerium and Yttrium show positive correlation with mineralization of radioactive materials (Uranium – Thorium). Considering the genetic relationship between these elements (Cerium and Yttrium), popular separation of anomalous elements carried out by using classical statistical methods for lithogeochemical data and calculated statistical parameters. Then, the frequency distribution histograms along the calculation were plotted and consequently, the separation of anomalous element populations carried out. High positive correlation among the radioactive elements (U & Th) and Rare Earth Elements such as Cerium and Yttrium indicated that their mineralization phase generated from the same origin. Compilation of geochemical and geological rock unit maps designated that the radioactive ore mineralization was controlled by metasomatism, which produced different types of albite metasomatite, amphibole metasomatite, and albite-amphibole metasomatite from the rocks of pyroclastics, diabase, dacite and gabbro in the area. Uranium and Thorium anomalies calculated by classical statistical methods are mostly distributed in the west, southwest, and central part of the area, but in the central part the Th-intensity relatively was stronger than the Uranium. The anomaly trend for Cerium and Yttrium are the same as the Uranium and Thorium, but Yttrium anomaly in the central part is more intensive than the others.
D Refahi; A Khakzad; N Nezafati; Kh Bahar Firozi; A Bayatani
Abstract
Development of advance tools in remote sensing and airborne geophysics during recent decades shows this industry importance. In this paper, aster sensor imagery (Advanced Space born Thermal – Radiometer) and airborne geophysics employed in order to zoning alteration area, mineralization system ...
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Development of advance tools in remote sensing and airborne geophysics during recent decades shows this industry importance. In this paper, aster sensor imagery (Advanced Space born Thermal – Radiometer) and airborne geophysics employed in order to zoning alteration area, mineralization system analysis and prospecting in 1:25000 Oghlansar sheet, which is situated in north of Sarab City in East Azerbaijan province. The area is located in structural zone of theEastern Alborz-Azerbaijan. The lithology of area contains Eocene-Neogene magmatic-volcanic complex such as andesite, rhyodacite, rhyolite, and granodiorite associated with pyroclastics such as tuffs, volcanic breccia and lava flows. In this investigation, we applied different methods of spectral analysis and normal classification such as SAM (Spectral Angel mapping), MF (Match Filtering) using ASTER images. Furthermore, spectral analysis methods on airborne geophysics data were engaged in order to extract shallow bodies and recognition of faults. ASTER imagery process and airborne geophysics data led to primary potential mineral map of the area. For credibility of results, 200 samples were taken and analyzed by XRD, XRF and ICP methods. Consequently, 190 samples (95%) confirmed the results of remote sensing and airborne geophysics processes. Conclusions of this research revealed that applying concurrency both the remote sensing and airborne geophysics data could be led to improve the precision of the results.
M.R Omidvar Ashkalack; A Khakzad; N Nezafati; M.A.A Mokhtari; B Borna; S Rozbeh Kargar
Abstract
The studied area is located in the western part of the Central Alborz structural zone and contains a bauxitic- lateritic horizon between the Elika and Shemshak formations. This horizon belongs to the middle Triassic, and croups out with E-W trend in the four regions (trends) including Zard Kuh- Loriteh, ...
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The studied area is located in the western part of the Central Alborz structural zone and contains a bauxitic- lateritic horizon between the Elika and Shemshak formations. This horizon belongs to the middle Triassic, and croups out with E-W trend in the four regions (trends) including Zard Kuh- Loriteh, Shagol- Sangrood, Abasak- Hir, and Arsheh Kuh- Zakabar. The complete cross section of bauxitic- lateritic horizon contain dark grey pisolites in the lower part, yellowish red laterite in the middle part, and an upper part with light grey color. Kaolinite and quartz are the main mineral components of this horizon. The minerals such as diaspore, bohemite, anatase, hematite and goethite present as minor phase. The grey- colored upper and lower parts contain high grade of Al2O3 and low grade of Fe2O3 while in the middle part, high grade of Fe2O3 and low grade of Al2O3. The average grades of Al2O3, Fe2O3, SiO2 and TiO2 in the samples are in turn 35%, 14%, 35% and 5%. The maximum grades of Al2O3 in the mentioned four trends are 51%, 61%, 48% and 48%. There is a distinctive negative correlation between Al2O3 and Fe2O3, between Fe2O3 and SiO2, and between Fe2O3 and TiO2. Furthermore, there is a positive correlation between Al2O3 and TiO2. The results of laboratory investigations indicated that the best bauxitic- lateritic horizon in the studied area considering grades of major oxides is the Abasak- Hir trend.
H Harati; A Khakzad; N Rashidnejad Omran; H Asadi Harouni; S.J Javad Moghaddassi
Abstract
The kahang Copper porphyry deposit on Urumieh-Dokhtar magmatic arc, is located in NE of Esfahan. Around of this deposit, Eocene volcanics and pyroclastic rocks ranging in composition from basaltic trachy-andesitic to dacitic are exposed. Granitoids subvolcanic and volcanoplutonic, the causes of alteration ...
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The kahang Copper porphyry deposit on Urumieh-Dokhtar magmatic arc, is located in NE of Esfahan. Around of this deposit, Eocene volcanics and pyroclastic rocks ranging in composition from basaltic trachy-andesitic to dacitic are exposed. Granitoids subvolcanic and volcanoplutonic, the causes of alteration and mineralizaton, replacement in Eocene rocks assemblage in afew puls from Oligocene to Miocene. This plutons ranging in composition from monzodiorite quartzdiorite granodiorite to granite with porphyroeidal texture. Alteration and mineralization is classically developed in this deposit. Samples from surface soil were collected in 50m profiles gridding which the distance samplings in along the profile are 25m. The total numbers of samples are 2564 which are analyzed by ICP-OES method for 43 elements. In geochemical anomaly maps, activating of faults with another tectonic factors, environmental conditions alteration and erosion in moving and concentration this anomaly are illustrated. Same as the litho geochemical anomalies the most amount distribution of Cu in the eastern and center of the region, Au in the west and center and Mo in all three region are depicted. In elemental correlation graphs suitable correlation is for Copper and Gold.