JOURNAL OF ECONOMIC GEOLOGY
Year:2020 | Volume:12 | Issue:1 (24)|Papers Count:6

Introduction The Western Alborz-Lesser Caucasus metallogenic belt includes important Cu and Cu-Au skarn, porphyry and epithermal deposits of Tertiary age in Iran, Turkey and Armenia (Karimzadeh Somarin and Moayyed, 2002; Karimzadeh Somarin, 2004). Important deposits such as Sungun and Masjed Daghi have been situated in this zone in Iran (Ghorbani, 2011). Some researchers have called this zone in the north-western part of the Iranian Copper belt Arasbaran Copper belt (Hassanpour et al., 2010). The Mazraeh deposit is located 20 km north of Ahar city between geographical longitudes '47 ° 00 and 47 ° 08', and latitudes 38 ° 40 '. In addition, 38 ° 36' is a part of Arasbaran Copper Belt in the Kaleyber’ s 1: 100000 geological map. In recent years, it has become possible to study subsurface samples in this deposit to a depth of 300 meters and provide the opportunity for extensive study of mineralogy and geochemistry of this deposit by conducting systematic exploratory drillings by the National Copper Corporation. Considering the relatively high amounts of gold in cores obtained from drill holes, the study of relationship between gold mineralization and other metals in this deposit has become important for assessing the mineral potential of this deposit. ...

Introduction Partial melting is an appropriate correlation process between metamorphism and magmatism which plays a key role in the development of migmatites, granulites and S-type granites during crust evolution (Kriegsman, 2001; Alvarez-Valero and Kriegsman, 2008; Sawyer, 2010). In this study, we tried to address the correlation between partial melting process and metapelites migmatization and the formation of adjacent granites through microscopic and field evidence and geochemical data....

Introduction Fe skarn deposits are one of the important Fe deposits in the Zanjan province which have been exploited in recent years. The Qozlou Fe deposit is one of these Fe skarn deposits which is located at 65 km west of Zanjan. In this area, alternation of micro-sparitic limestone, marly limestone, shale and sandstones of Upper Cretaceous were intruded by Late Eocene granitoids. This event caused to metamorphism contact and it caused the formation of Fe mineralization. Some of the Fe skarn deposits in the Zanjan province were studied during the past few years (e. g. Nabatian et al., 2017) and valuable information is present about their geological and mineralization characteristics. However, Qozlou granitoid and Fe deposit have not been studied yet. In this research, petrology and geochemistry of the Qozlou granitoid along with petrographic characteristics, mineralogy, structure and texture of Fe deposit and thermodynamic conditions for formation of contact metamorphic rocks have been studied....

Introduction It is generally understood that manganese deposits have a diverse origin, based on their mineralogy, chemical composition and tectonic setting. Marine Mn-bearing deposits are classified as hydrogenous, hydrothermal and also biogeneticbacterial deposits (Bonatti et al., 1972; Hein et al., 1997; Bau et al., 2014; Polgá ri et al., 2012; Schmidt et al., 2014). Hydrogenous processes can form ferromanganese crusts, which result from slow precipitation of seawater at the seafloor often via microbial mediation (Toth, 1980; Dymond et al., 1984; Bau and Dulski, 1999; Usui and Someya, 1997; Hein et al., 2000; Jach and Dudek, 2005). Diagenetic manganese deposits occur as nodules and precipitate from hydrothermal solutions or pore water (Polgá ri et al., 1991; Oksuz, 2011; Polgá ri et al., 2012), whereas hydrothermal ore deposits are stratabound or occur as irregular bodies and epithermal veins, where they are formed in a marine environment near spreading centers, intraplate seamounts or in subduction-related island arc setting (Roy, 1992; Roy, 1997; Hein et al., 2008; Edwards et al., 2011)....

Introduction In porphyry copper deposits, turquoise is considered to be a supergene oxidation product (John et al., 2010; Chavez, 2000). Based on Rezaian et al., 2003; Zarasvandi et al., 2005 and Eslamizadeh, 2004, the Aliabad index is introduced as a porphyry copper system. The first published report on turquoise events around Ali-Abad was presented by Momenzadeh et al., 1988. This area is located 57 km southwest of Yazd. Alterations often include siricitization, advanced argillization. Kaolinization and silicification have occurred frequently in the arkose and microcan glomerate of the Sangestan formation. The aim of this research study is to try to reconstruct and investigate the formation and origin of turquoise by using the latest mineralogical and geochemical data. Field evidence shows occurrence of turquoise in the form of a veinlet and nodules, with blue-green and blue-white colors. Jarosite, alunite, quartz and iron oxides are found together with turquoise....

Introduction Anthropogenic activities have a high impact on urban areas and lead to severe pollution in large cities. Urban soils are huge ‘ basins’ for accumulation of various pollutants. Thus, they also serve as informative media. Therefore, the study of urban soils has developed in recent years. Mashhad is the second metropolitan city in Iran which has more than 3 million residences and over 20 million annual pilgrimage tourists. This city is surrounded by numerous factories and the high growth of urbanization has led to accelerated air pollution. In this research study, new analytical data for heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Sn and Zn) in soil of parks in Mashhad are presented and they are compared with unpolluted non-urban soils. Then, the origin of soil pollution in park soils is discussed by statistical methods and Pb isotope values....