Prepare by: Pars Geological Research Center (Arian Zamin) August 2012
Position, boundaries and area of Iran Iran is located in southwest of the Continent of Asia like a bridge connecting three continents of Asia, Europe, and Africa. It is bounded to Azerbaijan, Armenia, Turkmenistan and Caspian Sea in north, to Afghanistan and Pakistan in east, Oman Sea and Persian Gulf in south, and to Turkey and Iraq in west. The country of Iran is part of Iranian Plateau that is a vast and high land, which is bordered with Caspian Sea in north, Amu Darya, Syr Darya and Kora River plains in northeast, Sindh and Punjab River plain in southeast, Oman Sea and Persian Gulf in south and Tigris River plain in southwest (Fig-1). The total area of the plateau is 2,600,000 km 2 of which approximately 1,648,195 km 2 is accounted for Iran and the rest covers Afghanistan, Pakistan and some former Soviet Union republics. The area of Iran is 3.7% of the area of the Continent of Asia and 1.09% of the total land on the Earth's land surface. Iran geographic coordinates are between 44 and 63 5 30 eastern longitude and 25 to 40 north latitude. The time difference with the easternmost point and westernmost point is about one hour and eighteen minutes. The perimeter of Iran is about 8700 km of which 2700 kilometers (or nearly one third) forms sea borders (Persian Gulf, Oman or Makran Sea and Caspian Sea) and the rest borders with land, rivers and lakes.
Fig-1: Iran geographic location and its neighbors
Administrative Division Based on the latest administrative division system provided posted on MOI (Ministry Of Interior of Iran) Website, Iran consists of: 31 provinces, 385 counties, 961 districts, 1120 cities, 2473 rural districts Demographic numbers
Geological Setting of Iran From a global tectonic point of view, Iran is part of the Alpine-Himalayan orogenic belt that extends from Atlantic Ocean to western Pacific. Most European and Asian geologists believe that this belt represents the Great Tethys Sea once located between two large continents, Gondwana and Eurasia, during Paleozoic-Mesozoic periods.
Structural Units of Iran Iran has been divided into several structural units, each characterized by a relatively unique record of stratigraphy, magmatic activities, metamorphism, orogenic events, tectonics, and overall geological style (Fig-2).
Fig -2 Structural map, metallogenic and mining provinces
Structural Units of Iran (continued) Central Iran Located as a triangle in the central part of Iran, Central Iran is one of the most important and complicated structural zones in Iran. In this zone, rocks of all ages, from Precambrian to Quaternary, and several episodes of orogeny, metamorphism and magmatism can be recognized. Sanandaj-Sirjan This zone is located to the south-southwest of Central Iran, and the northeastern edge of Zagros Range. A striking feature of this zone is the presence of immense volumes of magmatic and metamorphic rocks of Paleozoic and Mesozoic ages. Zagros This zone extends from Bandar Abbas in south to Kermanshah in northwest, and continues through to Iraq. Zagros is indeed the northeastern edge of the Arabian plate. Alborz Alborz range is located in northern Iran, parallel to the southern margin of Caspian Sea. Azarbaijan There are three scenarios for Azabaijan and its geological setting: It could belong to Central Iran. The northeastern corner of Azarbaijan could be included in Alborz, and the southeastern part in Sanandaj-Sirjan. Azarbaijan lies in a zone called Azarbaijan-Alborz, and this zone is bounded in north by Alborz fault, in west by Tabriz-Uromieh fault and in south by Semnan fault. The eastern boundary with Binalood zone is still controversial.
Structural Units of Iran Geological Zones of Eastern Iran Eastern Iran can be divided into two parts: Lut Block: located to the west of Zabol-Baluch zone. It extends for about 900 km in a north-south direction. Flysch zone (Zabol-Baluch): this zone is located between Lut Block to the west and Helmand (in Afghanestan) to the east. Southeastern Iran (Makran zone) this zone is located to the south of Jazmurian depression. Its western boundary is Minab fault; to the south it is restricted to Oman Sea and to the east it extends into Pakistan. Kopeh-Dagh This basin is located in the northeastern Iran. In this basin, a thick sequence of continuous marine and continental sediments were deposited (about 10 km). No major sedimentary gap or volcanic activities during Jurassic to Oligocene have ever been reported. This sedimentary complex provides suitable conditions for accumulation of hydrocabons.
Ophiolite series and ultramafic rocks of Iran Ultramafic and mafic units of Late Precambrian-Early Cambrian age (Takab and Anarak regions) Ultramafic and mafic rocks of Upper Paleozoic (Fariman, Shanderman and Asalam areas). Ophiolite series of Early Cretaceous-Paleogene age. These rocks show typical features of ophiolite sequences and are thought to be related to the closure of Neothetys. Kermanshah-Neyriz-Oman belt Makran (South of Jazmurian) Ultramafic-mafic rocks related to flysch zone in Khash-Nosrat Abad- Birjand belt Ultramafic and mafic rocks north of Dorooneh fault, Torbat Jam-Torbat Heidarieh-Sabzavar-Fariman regions Central Iran-Naeen-Baft-Shahr babak Khoy-Maku
Basement of Iran With regard to the available data on the geology of Iran and Middle East, and a comparison of the Iranian and Arabian basements, it seems that stabilization of the basement in Iran occurred in the Late Proterozoic to Early Cambrian. This is supported by similar Gondwanaian features in both Iranian and Arabian basements. It is believed that the Arabian shield was the continuation of Mozambique in Eastern Africa prior to the development of Red Sea. The cratonization happened transitionally from Africa toward Iran because Central Africa has a basement of Late Archean-Early Proterozoic while in the Northern Africa there is no Archean basement; besides the extent of Precambrian domains decreases from Central Africa towards north. The oldest known sedimentary unit in Iran is Kahar Formation, which is well exposed in Alborz and Azarbaijan. The uppermost layers show an age of about 650 million years based on the paleontology and stratigraphic evidence; the basal layers are thought to be as old as 800 my. The oldest rocks in Iran, based on the radiometric ages, are as old as 900 million years. This is the time when Doran-type granites and Gharehdash series appeared.
Numbers and statistics about mineral deposits and fossil fuels reserves in Iran Proven and probable reserves of metallic and nonmetallic deposits of the country is proclaimed to be around 55 billion tons. There are 62 types of mineral deposits in Iran, which puts it in the category of countries having large number of mineral deposits with high variety (Table-1).
Table-1 Deposits of Iran by category
Main mineral deposits and fossil fuel reserves in Iran The next slides show numbers and statistics about main mineral deposits and fossil fuel reserves in Iran as compared to the world.