Dominant structural trends in Zagros province (Figure 2) are NW-SE in northwestern part and E-W in southeastern

part. From tectonics view, it contains the overthrust and simple fold belts of Zagros that formed on the northeastern part of Arabian plate’s passive margin (Figure 1).

Zagros Mountains have continued to East Taurus Mountains in Turkey and have named Zagros-East Taurus hinterland. Zagros-East Taurus hinterland is external platform (fold and thrust belt) of north margin of Arabian Craton (Figure 1). Vergence of folding in this hinterland is toward south and southwest.

Dominant structural trend in Persian Gulf foreland basin province (Figure 2) is NW-SE. From tectonics view, it contains the south margin of simple fold belts of Zagros that formed on the northeastern part of Arabian plate’s passive margin. Persian Gulf has continued to end of Mesopotamian area in central Iraq and have named Persian Gulf-Mesopotamian foreland basin. Persian GulfMesopotamian foreland basin is north margin of internal platform of north margin of Arabian craton (Figure 1).

Dominant structural trend in Makran province (Figure 2) is E-W. From tectonics view, it contains the accretionary prism on trench of Oman sea subduction that has continued to Pakistan (Figure 1). Makran accretionary prism has 150 (Iran) to 350 (Pakistan) Km width that its north

part uplifted and formed Makran range.

Dominant structural trend in Bashagard province (Figure 2) is E-W. From tectonics view, it contains upper slope part of Makran accretionary prism that has terminated to East Iran Mountain belt (Figure 2). Bashagard province is a sign for bending zone of Arabian oceanic lithosphere.

Dominant structural trend in Jazmorian province (Figure 2) is E-W. From tectonics view, it contains a fore arc basin (Jazmorian plain) that has continued to Mashkel plain in Pakistan (Figure 2). Jazmorian-Mashkel fore arc basin has formed on south margin of East-Central Iran microcontinent and filled by Paleogene Turbidities and Neogene-Quaternary terrestrial sediments. Note that low seismicity in Makran and Jazmorian provinces has related to slow subduction rate and steeper dip of Benioff zone. Current subduction rate of oceanic crust (related to late Cretaceous) is 19 millimeters per year [11].

Dominant structural trend in Shahsavaran-Soltan province (Figure 2) is E-W. From tectonics view, it contains an active magmatic arc that has continued to northeast in Pakistan. Shahsavaran-Soltan magmatic arc has formed on south margin of East-Central Iran microcontinent and it contains 16 Quaternary eruptive centers with 450 km length.

Dominant structural trend in South Lut province (Figure 2) is E-W. From tectonics view, it contains a retro arc back arc basin that has continued to Helmand plain in Pakistan. South Lut-Helmand back arc basin has formed on south part of East-Central Iran microcontinent and it contains 2 Km Tertiary volcanic rocks eruptive centers with 450 km length.

Dominant structural trend in East Iran province (Figure 2) is N-S. From tectonics view, it contains the magmatic arc and its accretionary prism belt that is result of westward subduction of west Afghanistan microcontinent (Figure 1) beneath to East-Central Iran microcontinent.

Therefore, East Iran province has named Sistan or East Iran suture zone too. Recently, a dextral transpression zone (Nehbandan fault system) has developed on the eastern border of this province that it marked by horsetail splays on the northern and southern terminations (Figure 2).

Dominant structural trend in West-Central Alborz and lesser Caucasus province (Figure 2) is NW-SE. From tectonics view, it contains deformed zone (fold and thrust belt) of Cimmerian miniplate (Figure 1) that formed in northern active margin until late Triassic. Then it has rifted by tension in a back arc basin of Neotethyian subduction zone in the south margin of Cimmerian miniplate. Development of that rift stopped in the late Cretaceous and then, renewed in the Eocene by spreading in submarine arc basin of Neotethyian subduction zone. In the other word, this hinterland is result of a magmatic arc system [12] spreading in the evolutional back arc basin. After that, West-Central Alborz and lesser Caucasus hinterland has formed by deformation and regional uplift from SW part of Caspian Sea to Black sea.

Recently, Damavand and Sebalan cones have formed by late volcanism that related to final subduction of oceanic slab in south Caspian basin toward south and southwest. Five dominant orogenic phases and four deformational events in Alborz Mountain building processes have suggested by [13].

The first deformational event is one from the Syn-collision type between Cimmerian and Eurasian plates (late Triassic) and the other ones are from post-collision deformational events and in with the deformational of sedimentary cover which is result of shortening and increasing the thickness of passive continental crust in north of Cimmerian miniplate.

Dominant structural trend in Great Kavir-Northern Urmieh lake province (Figure 2) is NW-SE. From tectonics view, it contains the southern foreland basin of WestCentral Alborz and lesser Caucasus hinterland in the north margin of Cimmerian miniplate (Figure 1) since late Eocene.

Also, this foreland basin in Pishva (Varamin) is a piggyback basin that formed on thrust sheets. In Tehran area, this basin is a deformed basin [14] by active thrusting in footwall of North Tehran fault.

Dominant structural trend in South Great Kavir fold and thrust belt province (Figure 2) is NE-SW. From tectonics view, it contains fold and thrust belt that formed on the south margin of North-Central Iran microcontinent (Figure 1). This belt have deformed by collision of NW part of East-Central Iran microcontinent with North-Central Iran microcontinent, on the passive margin setting. South Great Kavir fold and thrust belt is a peneplain like area by extensive erosion.

Dominant structural trend in South Caspian-Black sea foreland basin province (Figure 2) is NW-SE. From tectonics view, it contains the northern foreland basin of West-Central Alborz and lesser Caucasus hinterland in the south margin of Eurasian plate (Figure 1) since late Eocene. Although, median part of South Caspian and Black sea basin has uplifted by collision between Eurasian and Cimmerian plates.

Dominant structural trend in Urmieh-Dokhtar province (Figure 2) is NW-SE. From tectonics view, it contains a magmatic arc that is result of subduction to beneath of southern active continental margin of Cimmerian plate. Also, Sahand and other cones (about 9) in lesser Caucasus hinterland are result of quaternary magmatism in this zone that it has marked by widespread Eocene volcanism. Urmieh-Dokhtar province has continued to south of Black Sea and Its width has increased from Naien city that many parts have covered by quaternary deposits of Dagh Sorkh Kavir, Southern Urmieh Lake, Namak and Hoz-e Soltan Lakes have formed on it. So, there are a few backland basins with Playa type sedimentation because of dip decreasing in Ben off zone (in NW part of magmatic arc). SE part of magmatic arc has formed on southwest margin of East-Central Iran microcontinent.

Dominant structural trend in Naien-Kerman province (Figure 2) is NW-SE. From tectonics view, it contains a retro arc foreland basin on the north margin of UrmiehDokhtar magmatic arc (SE part). Davaran Mountain and Bafgh-Baghin fault system [15] have developed in this province that formed on southwest part of East-Central Iran microcontinent.

Dominant structural trend in Sanandaj-Sirjan province (Figure 2) is NW-SE. From tectonics view, it contains Sanandaj-Sirjan overthrust belts that formed by metamorphic rocks of the northeastern part of Arabian plate [8]. This province has continued to the north part of Dead Sea fault in the south Turkey. Late Cretaceous-Paleogene sequences in this belt have piled up on a wedge top part [16] of Zagros proforeland basin [17], before regional metamorphism. Recently, pre-Cretaceous deformed and metamorphic rocks have exposed in this province by upthrusting of basement wedges (Figure 3).

Quaternary basins such as southern margin of Urmieh Lake, Kabodarahang depression, Mighan Kavir, Gavkhoni depression, Abarkuh Kavir, Marvast Kavir and Sirjan’s Kavir-e Namak, on the north boundary of this province with Urmieh-Dokhtar are the index cases from Supra-Arc troughs. These basins are significant in marking loss of the fore-arc basin beneath back-thrusts antithetic to the subduction direction and can explain the presence of younger molasse in a setting referred to as a suture zone [19].

Dominant structural trend in East Alborz province (Fig-

ure 2) is NW-SE in eastern part and NE-SW in western part. From tectonics view, it contains Binalod magmatic arc and its fore arc basin with volcanic activities (especially in Silurian) on northeastern of Cimmerian miniplate. Obduction of Mashhad ophiolite during late Paleozoic has result of subduction into beneath this province (Figure 4) but marine sedimentation on Kopet Dagh proforeland basin (Over thinned crust of south Eurasian plate) has continued to Eocene. Also, East Alborz fore arc basin gradually uplifted and it has formed a hinterland with SW vergence.

Dominant structural trend in Torbat-e Jam-Neyshabour province (Figure 2) is NW-SE in eastern part and NESW in western part. From tectonics view, it contains the Torbat-e Jam-Neyshabour retro arc foreland basin on northeastern part of North-Central Iran microcontinent.

A magmatic arc has formed on north and parallels to this province that it has underthrusted beneath East Alborz province since Paleogene. Torbat-e Jam-Neyshabour retro arc foreland basin has filled by erosion of that magmatic arc.

Dominant structural trend in Kopet Dagh province (Figure 2) is NW-SE. From tectonics view, it contains the Kopet Dagh hinterland or Kopet Dagh fold and thrust belt that formed in passive margin of Eurasian plate until late Triassic and then marine sedimentation on Kopet Dagh proforeland basin has continued to Eocene.

Kopet Dagh hinterland has uplifted related to Karakorum foreland basin in northeast along Eshghabad fault.

Dominant structural trend in South Caspian province (Figure 2) is NW-SE in eastern part and N-S in western part. From tectonics view, it contains the South Caspian remnant oceanic basin [21] and northern foreland basin of Central Alborz hinterland.

Therefore it is a hybrid basin over an old island arc that it has formed by southward Paleotethyan intraoceanic subduction. This province is subducting beneath to Apsheron-Sill ridge [22] on north boundary of South Caspian now [23].

Dominant structural trend in Great Kavir-Taibad province (Figure 2) is NW-SE in eastern part and NE-SW in western part. From tectonics view, it contains the Maiamay-Taibad marginal back arc basin with Sabezevar Ophiolites and Torbat-e Heydarieh volcanic rocks that inverted in paleogene.

Dominant structural trend in Khaf-Bardeskan province (Figure 2) is NW-SE in the eastern part and NE-SW in the western part. From tectonics view, it contains the northern active margin of East-Central Iran microcontinent (Figure 1). It has formed by southward subduction of oceanic lithosphere (under Maiamay-Taibad marginal back arc basin) that named Sabzevar Ocean [24].

Lut Plain-Gonabad back arc basin on the Lut microcontinent (eastern portion of East-Central microcontinent) has placed on the west of East Iran Mountain belt.

Dominant structural trend in East-Central Iran province (Figure 2) is N-S. From tectonics view, it contains back arc (retro arc) basin that it has related to westward subduction of west Afghanistan microcontinent beneath to East-Central Iran microcontinent. Recently, horsetail splays in northern termination of Nehbandan fault system have developed in the northern part of this province.

Dominant structural trend in East-Central Iran province (Figure 2) is N-S. From tectonics view, it contains an ancient island arc on the west of the Lut Plain-Gonabad province that it has accreted to this along Nayband fault system (western border of the Lut microcontinent) by eastward subduction in Pre-Cambrian.

Dominant structural trend in East-Central Iran province (Figure 2) is N-S. From tectonics view, it contains a few ancient island arcs [25] that they have accreted together by eastward subductions [6].

Neoproterozoic-Phanerozoic Tectonic column in Cimmerian miniplate under Iran country area (Figure 1) are at least contain 8 tectonic stages between 7 below events:

1) Compressive event of late proterozoic (Pan African orogeny); 2) Tensional event of Infra-Cambrian-Late Paleozoic (equivalent to movements of Caledonian and Hercynian orogenies) that it has marked by some sedimentary gaps such as in lower Paleozoic and Carboniferous sequences on the Alborz basin; 3) Compressive event of late Triassic (Early Cimmerian orogeny); 4) Tensional event of Late Jurassic; 5) Compressive event of Late early Alpine orogeny; 6) Tensional event of the Middle Alpine orogeny; 7) Compressive event of the Late Alpine orogeny.

Two later tensional events are related to back arc spreading (Figure 6) that it has been inverted by consequence compressive events.

Neoproterozoic-Phanerozoic Tectonic column in Eurasian plate under Iran country area (Figure 1) are at least contain 5 tectonic stages between 4 below events:

1) Compressive event of late proterozoic (Cadomian orogeny); 2) Compressive event of Late Paleozoic (Hercynian orogeny); 3) Compressive event of late Triassic (Early Cimmerian orogeny); 4) Compressive event of the Late Alpine orogeny.