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Geomorphic indices are useful tools for studying relative active tectonics of a specific area. In this study, the relative active tectonics of Bozgoush region (NW of Iran) has been investigated based on Geomorphic indices. The studied indexes include: the stream length-gradient (SL), hypsometric integral (Hi), the ratio of valley floor width to valley height (Vf), the shape of the drainage basin (Bs), the sinuosity of mountain front (Smf), asymmetric factor of drainage basin (Af) and transverse topographic symmetry factor (T). In the present study, gathered data from various morphometric indexes of six basins are aggregated, and their obtained result is provided as relative active tectonics of the region or Iat index that shows a proper illustration of the relative active tectonics of the mentioned region. In order to develop a correct analysis of the mentioned area, the AHP (analytic hierarchy process) model with a studied weight, the final overlapped layer of relative tectonics is prepared with applying coefficients. With the comprehensive field studies, evidences like deep valleys, river bed immigration, landslides, sudden change in river cycles and surfaces of faults were found that are in good consistence with obtained data of relative active tectonics of the region. After measuring these indexes, it was found that Aydoghmush and OujanChay basins have a high relative active tectonics. With regard to the obtained results of present study, it seems that Tabriz fault has the most seismic and motional potential in northern basins of the region. In addition, in Aydoghmush basin, in southern part of the region, Qeynarjehchartagh fault has a high active tectonics that according to the estimated values has been identified as an active young structure in the region.

The Late Jurassic aged Lisar granite in North Iran is in tectonic contact of the form of thrust and strike slip faults with Upper Cretaceous sandy limestone and is covered by Paleogene polygenetic conglomerate in the Talesh Mountain at the western continuation of the Alborz range. The rock samples of the granite are pink coloured and coarse-gained with K-feldspar, quartz, plagioclase, biotite and amphibole. The Lisar granite is more likely emplaced in an extensional environment indicated with numerous space fi lling silica-rich aplitic veins in the rocks. The granite samples are moderately altered and feldspars are changed to sericite and clay minerals and biotite is partially converted to chlorite. The Lisar granite has derived from a high K magma and is A-type in nature, belonging to A 2 subgroup. The rock samples of granite are characterized by distinct negative Eu anomaly and a decrease from LREE to HREE contents. The parental melts of the granite were generated from partial melting of a lower continental crustal source with possible contribution from the mantle materials. The Lisar granite represents Cimmerian post-collision magmatism in north Iran following closure of Palaeotethys Ocean and subsequent collision. IntroductionPalaeomagnetic studies show that Iran was a part of Gondwana up to Early Carboniferous (Alavi, 1991;Majidi, 1991;Mirnejad et al., 2013; Shafaii Moghdam et al., 2015), Gorgan schists (Ghavidel et al., 2007;Delaloy et al., 1981), metamorphic rocks of the Gasht and Masuleh area (Clark et al., 1975) and Shanderman eclogites (Zanchetta et al., 2009;Omrani et al., 2013). The Palaeotethys suture can be traced to the east to Afghanistan and China and towards the west into Turkey . The Palaeotethys ocean closed 225 Ma ago which followed by uplifting of the Turan plate and emplacement of allochtonous nappes on the Iranian plate (Stampfl i, 1993). Magmatic activities, especially granitoid magmatism, related to the Palaeotethys subduction are well documented along the suture in China. The magmatic arc at Yunnan area (southwestern Yunnan, China), with basaltic-andesitic to granodiorite composition has an age of 292-282 Ma (Hennig et al., 2009). I-type and S-type granitoids of Hindu Kush in Afghanistan have ages of 210, 112 and 193 Ma, respectively (Debon et al., 1987). These granites with roughly Triassic age are traced westward into east of Iran, where the Binalud granites and granodiorites, dated 256 to 211 Ma (Majidi, 1978;Berberian and Berberian, 1981), are intruded into * Corresponding author: Mohssen MOAZZEN moazzen@tabrizu.ac.ir

Regarding the seismicity of the Zagros and the Red Sea regions, the present study has investigated and analyzed the seismicity with M ≥ 5 of these regions with obtaining seismicity coefficients, geometrical characteristics including depth, earthquake dispersion and focal mechanism of earthquakes, and their relation to each other. The estimated b-value for these two zones is approximately the same, being equal to ∼1.2. However, the total number of earthquakes in the Zagros is much higher (approximately 5.5 times), when the ratio of small to large earthquakes is about the same amount. In this study, focal depth of more earthquakes occurred and located in the Zagros and Red Sea respectively in depth of 15–20 km and 10–15 km from the earth surface, indicating that the Zagros Crust is thicker than the Red Sea.