Document Type : Research Paper
Author
Master of Economic Geology
Abstract
The plate tectonics is a new model for classification of sedimentary environments and lithofacies. Based on this model, Iran is divided into several different units, and each unit has its own sedimentary basins of lithofacies and, as a result, specific mines. The rift birth process in the Central Iranian Plateau crust and during Infra-Cambrian has been associated with formation of iron, nickel, cobalt, copper and magnesite mines. The Alborz orogenic belt is the result of closure of the Tethys Sea and is considered to be the site of collision of the Iranian Plate with the Turan Plate. In this belt, foreland basins are the site for the formation of coal reserves. Volcanic activities of the third era have brought about mines of volcanic and vein type in the Alborz.
The Zagros orogenic belt has been formed and is still dynamic due to submergence of the crust of the New Trthys Ocean under the micro-continent of Iran and during the collision of this micro-continent and the shield of Arabia. In this orogenic belt, Khuzestan plain and the folded Zagros belt are the focus of massive reserves of hydrocarbons. High Zagros ophiolites are sites of chromite reserves. Sanandaj-Sirjan area is a fore-arc basin, and the Isfahan-Malayer mineral belt in this area contains countless indices of lead and zinc sedimentary volcanic mines. Finally, the volcanic belt of Urumieh-Dokhtar is considered as the volcanic arc of the shell subduction system of the New Tethys Sea, and it is known in Iran as the copper belt.
The Lut block is part of the Iranian micro-continent, and the Diorite granite masses of Zahedan - Dehslam and Bazman are considered to be products of active continental margin, have been formed with the opening of the New Tethys Sea and contain tin and tungsten minerals. Plutonic volcanic belt at the southern edge of the Lut block is considered as a volcanic arc caused by submergence of the crust of the New Tethys Sea. This volcanic belt is a great source of copper and molybdenum copper deposits.
The lithofacies complex of Iran’s eastern mountains is the product of the opening of the basin between continental parts. This basin was accompanied by formation of oceanic crust, and its ophiolites have high potentials for chromite. Magnesite and asbestos ore mines are also among the characteristics of these ophiolites.
Study of dispersion of mineral reserves in tectonic units and different lithofacies is considered as an appropriate guide for seeking mineral resources.