Assessment of Relative Active Tectonics in the Bozgoush Basin (SW of Caspian Sea)

Abstract

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.

Old lake versus young taxa: a comparative phylogeographic perspective on the evolution of Caspian Sea gastropods (Neritidae: Theodoxus )

“…In conjunction with the regression, it is not unreasonable to think many of the rivers draining into the Caspian Sea may have become seasonal or dried out for short periods affecting their suitability as refugia. Furthermore, tectonic activity in the Caucasus and Alborz mountains may have affected the lifespan and suitability of springs as refugia [63][64][65][66]. Comparable examples of dramatic and sustained low stands have been shown for some ancient lakes to reduce diversity in groups to a single lineage [67].…”

Evolution of the Edea‐Eseka geomorphic units: A 'natural laboratory' of a prototype active rifting cross‐cutting the Southern Cameroon (West African) passive margin

“…The drainage network analyses aims to identify areas experiencing rapid tectonic deformation using Keller () and Keller and Pinter () geomorphic indices, notably: the hypsometric integral (HI) is used to evaluate the preserved portion of basin to the erosion; this parameter was developed by Strahler () giving the formula HI = ( H mean – H min )/( H max – H min ). According to values of HI, three types of basins can be discriminated (Dehbozorgi et al, ; Pérez‐Peña, Azañón, & Azor, ; Ritter, Kochel, & Miller, ): HI > 0.6 for young basins characterised by most of topography higher to the mean; 0.3 < HI < 0.6 for mature basins related to extensive, long‐term erosion and dissected drainage basins, and HI < 0.3 for old basins corresponding to peneplains; to constrain the tilting of the basin over a relatively large area, we used: (a) the asymmetry factor A F = (Hare & Gardner, ; Keller & Pinter, ; Pérez‐Peña et al, ); (b) the transverse topography symmetry factor TTSF = Da/Dd, very efficient to evaluate if the tilting is related to by tectonic activities (Alipoor, Poorkermani, Zare, & El Hamdouni, ; Cox, ; Eynoddin, Solgi, Pourkermani, Matkan, & Arian, ); the uplift under homogeneous lithological and climate (Wobus et al, ) was evaluated thanks to the normalised steepness index (Ksn) with Ksn = K s * A cent (Θref‐Θ) and A cent = 10 (logAmax + logAmin)/2 . We used a constant concavity (Ɵ ref = 0.45) as proposed in recent studies (Andreani & Gloaguen, ; Azañón et al, ; Gaidzik & Ramirez‐Herrera, ); the drainage density Dd (Km/Km 2 ) = ΣLu/A (Horton, ) that depends of the geology (lithology and tectonics) determined in the objective to reveal uplifting areas; the watershed slope S = H /Lb (Pareta & Pareta, ) and the deviation Dv (m) of Mvondo Owono et al () that aims to compare different river profiles and to reveal their control by lithological variations or base‐level changes (Ambili & Narayana, ; Nsangou et al, ); the concavity index IC = 2A/H of river profiles calculated in order to compare quantitatively longitudinal profile forms in different rock types and sub‐basins that are undergoing differential erosion, where river tectonically active shows higher concavity indices whilst equilibrated river profiles show lower concavity index (Ambili & Narayana, ; Bull, ). …”

Geomorphic Indices of Tectonic Activity Through the Analysis of the Drainage Systems in Pera Magroon Anticline, Northeastern Iraq

“…These classes are class 1 (of very high activity), class 2 (of high activity), class 3 (of moderate activity), and class 4 (of low activity). The regions with relatively high tectonic activity correspond mostly to the active structures in the basin (Eynoddin, 2017) which are shown in Table (7).…”