JOURNAL OF ECONOMIC GEOLOGY
Year:2020 | Volume:12 | Issue:3 (26)|Papers Count:9

Introduction: The study area is located in the Khorasan Razavi Province, NW of Gonabad between 58° 33˝-58 ° 38˝ to the east and 25° 34˝-25° 38˝ to the north. Geotectonically, the area is located in the northern part of the Lut Block. The Lut Block is the main metallogenic province in the east of Iran (Karimpour et al., 2012). There is a significant outcrop of Tertiary intermediate volcanic and pyroclastic rocks in the northwest of Gonabad. This region is rich in clay (kaolin) mineralization. The source of these kaolin deposits (argillic alteration) is related to a granitic dyke that intruded into the Shemshak Formation...

Introduction: The Sarcheshmeh porphyry copper deposit (PCD) and other porphyry deposits occur in the the most important metallogenic belt in Iran, i. e. the Urumieh-Dokhtar magmatic belt (UDMB). The main phase of intrusion generation in various episodes of mineralization in the Sarcheshmeh area is a stock of granodiorite to tonalite (Shahabpour and Kramers, 1987) that is called the Sarcheshmeh porphyry. This stock intruded volcano-sedimentary rocks and alteration has centered on it. The oldest rock units of the area are Eocene volcanic rocks (Waterman and Hamilton, 1975), which are mainly andesites accompanying marine sedimentary rocks that is consistent with a submarine volcano-sedimentary basin environment. Granodiorite and quartz eye porphyry crop out in the northern part of the Sarcheshmeh PCD. The main objective of this study is to investigate their petrology and geotectonic environment...

Introduction: Iron oxide-apatite deposits (IOA) are considered to be Kirune-type iron ores which have been formed during Proterozoic to Tertiary eras in different parts of the world. They usually have a connection with calc-alkaline volcanic rocks (Hitzman, 2000). Apatite occurs as a major constituent of these deposits which is accompanied with magnetite and some actinolite. One of the most important features of these deposits (Frietsch and Perdahl, 1995) is higher concentration of REEs. There are some iron oxide-apatite deposits in the Tarom-Hashtjin magmatic-metallogenic belt, northwestern Iran. The Golestan Abad iron oxideapatite deposit is one of the IOA deposits at the Tarom-Hashtjin belt which is located about 30 km east of Zanjan. The Golestan Abad deposit was studied during the exploration studies, but its geological characteristics, mineralogy, texture, geochemistry and genesis have not been studied yet...

Introduction: The Seh Qaleh agates, located at 120 km NW Birjand, are parts of Central Iranian (Lut block) (Aghanabati, 2004) with geographic coordinates of 58˚ 00′ to 58˚ 30′ longitudes and 33˚ 00′ to 34˚ 00′ latitudes. The host rocks of the agates are Eocene-Oligocene tuff, andesite and basalt. Silica mineralization in the area has occurred inside the volcanic units in the form of filling cavity and fractures. Here, the agates have very attractive textures such as concentric, flow and dogtooth textures that are accompanied with jasper, amethyst, opal, calcite and gypsum. Although Seh Qaleh agates are attractive and delightful, with high economical values, there is no scientific research about them. Therefore, their petrography, geochemistry and Raman spectroscopic characteristics are reported in the present paper for the first time...

Introduction: The Chah-Mesi polymetallic vein-type ore deposit, located 40 km north of Shahre-Babak city and 1. 5 km southwest of Miduk porphyry copper deposit, is situated in the Dehaj-Sarduieh belt as a part of the Urumieh– Dokhtar magmatic Arc (UDMA) (Figure 1). The main objectives of this research study are to investigate: (1) characterization of multi-element distribution associated with Cu mineralization, in order to demonstrate prediction of elemental concentration applied to identify high-grade ore bodies, (2) evaluating the interrelationships between copper, molybdenum, iron, led, zinc, gold and silver...

Introduction: The Iranian plateau is part of the Alpine-Himalayan orogenic belt, which consists of several continental fragments separated from each other by major boundary faults and/or ophiolitic suture zones (Gansser, 1981). Generally, the tectonic evolution of Iran has been controlled by the opening and closure of the Proto-Tethys, Paleo-Tethys and the Neo-Tethys during the Precambrian-Cambrian, Paleozoic and Cenozoic, respectively. The study area is located in the northwest of Iran (the Kurdistan province) and 20 km northeast of the city of Saqez. This area is a part of the northern Sanandaj-Sirjan Zone (Aghanabati, 2005). This belt is response to opening and subduction of Neo-Tethyan oceanic crust beneath the Central Iran (Alavi, 1994). During Cretaceous-Tertiary eras, numerous granitoid bodies were formed in this belt...

Introduction: The Robaie copper area is located 95 kilometers South of Damghan in the Semnan province. The study area has coordinates between 54˚ 30΄ 37˝ to 54˚ 30΄ 42. 71˝ latitude and 35˚ 22΄ 29. 41˝ to 35˚ 23΄ 47. 54˝ longitude. Geotectonically, the study area is located in the central Iran and in the northern part of the Torud-Chahshirin volcanicplutonic belt (Houshmandzadeh et al., 1978). The Torud-Chahshirin volcanic-plutonic belt is a Tertiary magmatism in central Iran which is composed of volcanic rocks with dominant andesite composition and granodiorite intrusive with dominant diorite composition (Fard et al., 2001). Torud-Chahshirin volcanic-plutonic belt has created a favorable geological situation for base metals such as copper, lead, zinc, gold, silver and other precious and base metals, such as the Robaie copper area, Chah Messi (Cu± Pb-Zn; Imamjome et al., 2009), Kuh-Zar (Cu-Au; Rohbakhsh et al., 2018) and other instances. The main objective of this study is geology, petrography, U-Pb zircon dating and Sr-Nd isotope and also alteration, mineralization, geochemistry and fluid inclusion in the study area...

Introduction: The Ni-laterites were mostly derived from ultramafic rocks in ophiolite complexes during weathering in tropical climate. Lateritization processes result in leaching of some major elements (Si and Mg) from the source rocks and concentration of some others (Ni, Fe, Cr and Co) in the residual soils. The Ni-bearing laterites are divided into three major subgroups including oxides, silicates and clay types (Berger et al., 2011). Hematite and goethite are the main constituents of the oxides type, whereas garnierite is the main carrier for Ni in silicates type. In the clay laterite, saponite and smectite are the main Ni-carriers. The Bavanat region contains Ni-bearing laterites as discontinuous outcrops which have formed on ophiolite ultramafic rocks in the northeast Fars province. These ultramafics are remnants of Neo-Tethys oceanic lithosphere which have been emplaced on continental margin along the Zagros Suture Zone in the Late Cretaceous era (Rajabzadeh, 1998). These laterites have recently attracted some geologists to work on them (e. g. Khademi and Hasheminassab, 2010; Rasti and Rajabzadeh, 2017). The aim of this study is to determine the effects of pH, organic matter (OM) and weathering intensity on the geochemical and mineralogical characteristics of Ni-laterites in the Chesmeh Rostami area, Bavanat region...