D Mokhtari
Abstract
The fluvial systems and landscape of the semiarid environments of northwestern Iran have preserved evidence of Quaternary environmental and tectonic changes. Djolfa-Hadishahr tectonic depression is a plain along Aras River in this territory. Data on the fluvial systems have been synthesized to evaluate ...
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The fluvial systems and landscape of the semiarid environments of northwestern Iran have preserved evidence of Quaternary environmental and tectonic changes. Djolfa-Hadishahr tectonic depression is a plain along Aras River in this territory. Data on the fluvial systems have been synthesized to evaluate the roles of tectonic, base-level and environmental factors in plain landscape. The satellite images were used to determining of morphometric characteristics and limiting the boundaries of studied drainage basin and alluvial fans limitation. Structural features analyzed via geological and geoelecteric sections and field studies included: thickness, orientation, fault effectuality and stratification. The results showed that geomorphologic and morphometric characteristics of fluvial systems specially on alluvial fans, influenced severely by Quaternary tectonic, base-level and other environmental changes. Because nowadays Djolfa-Hadishahr plain evolution is controlled by human constructive activities, this research emphasize on geomorphological considerations before every landscape changes in study area. This considerations could explain the human impact on plain nowadays and at the future via analyzing of main morphodynamic features.
D. Mokhtari; M. R. Nikjoo
Abstract
Tectono-geomorphologic features such as pressure ridges along strike-slip faults provide a reliable way to determine the fault displacement. The E-W trending active and strike-slip northern Mishow Fault is continuation of great Tabriz fault, that its ...
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Tectono-geomorphologic features such as pressure ridges along strike-slip faults provide a reliable way to determine the fault displacement. The E-W trending active and strike-slip northern Mishow Fault is continuation of great Tabriz fault, that its activity has created numerous geomorphologic traces. We document pressure ridges about Baghlar basin as a geomorphic effect of northern Mishow fault, based on tectono-geomorphic interpretation of field geologic and geomorphic observations. our results show that Pressure ridges of study area by the names of Sisdah and Tapah-Bashy, are developed along northern Mishow fault, which resulted from long-term tectono-geomorphic growth in Quaternary, specially. Present pressure ridges development indicate neotectonic movements in the study area. Occurrence of three phenomena of river diversion, river capture and continous go back of elbow of capture in a small segment of Baghlar basin, are the most important effects of high dynamics and durability of slope instabilities in pressure ridges. This case study, thus, provides a good example for understanding the long-term tectono-geomorphological evolution of a major intracontinental strike-slip fault.
D. Mokhtari
Abstract
Tabriz fault, oriented NW to SE, on its NW continuation that includes Mishow northern fault, is a right- lateral strike-slip fault and one of the most seismically active zones in Azerbaijan of Iran. Studies on different parts of this fault indicate that there are numerous geomorphologic ...
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Tabriz fault, oriented NW to SE, on its NW continuation that includes Mishow northern fault, is a right- lateral strike-slip fault and one of the most seismically active zones in Azerbaijan of Iran. Studies on different parts of this fault indicate that there are numerous geomorphologic features due to tectonic activities along it. Sag ponds are one of the features that in spite of their importance from geologic, geomorphologic and tectonic point of view have not been studied in this area. Therefore, this paper attempts to study several sag ponds along Tabriz and northern Mishow faults including Bostan-Abad Ghouri-ghol, Payam, Aralan, and Mishow Ghouri-ghol dry sag ponds. An introduction to sag ponds as a geomorphic effect of the strike-slip faults to recognition of active faults is the main goal of the paper.
All of these sag ponds are bounded by stike-slip and normal faults, subjects for previous investigations, field observations and geomorphic indices such as offset and deflected drainage and displaced terraces and alluvial fans. Obtained results from sag ponds and infilling of these basins by young Quaternary deposits indicate that Tabriz and northern Mishow faults are active faults, capable of generating relatively strong earthquakes in the future.