The depressed basins of northwest central Iran are located in the structural Step and between Soltanieh-Ipac-Koshk-e-Nosrat and Qom –Zefreh system (the Indes - Qom –Khurabad faults). The main process of deformation within the basin with extension and compression of specific structures are comparable and verifiable using experimental models. The extensional structures include roll-over folds and normal faults, resulting in deep sedimentary basins during deposition of the lower and upper red formations. The younger structures, includes back-thrusts and for-thrusts, shortcut, and pop up structures represents the reversal of tectonic of primary extensional basin. These sedimentary basins have been created in relation to the growth faults and hanging wall blocks So In the presence of roll-over fold and antithetic and synthetic faults therefore are suitable for entrapment of hydrocarbons during migration. The active structural features have been identified using combination of geomorphic characteristic and seismic reflection data. Accordingly, none of the old normal faults in the Saveh- Qom and Aran basin show at the present any extensional movement and the fault activity of boundary faults and extensional folding are compressional. The active parts are: hanging wall of Saveh, restraining bending at the end of Indes fault that has stream Length-Gradient (SL) index and high value hypsometric index (Hi). The central part of Saveh-Qom and Aran basin, although show high Hi but the SL is low. This situation is due to the moderating effects of the thick lower and upper red formations and evaporative layer within the basin. In the Aran basin due to incomplete coverage of seismic lines the absence of normal faults cannot be definitively confirmed. However, the center of Aran basin as of Qom-Saveh formed push up which marks the compression of this basin and also activity of reverse and thrust faults. Based on the existing surface and subsurface data set, active deformation in this area now is transpression basin and the interior domains are in the uplift.
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