M Ebrahimi; H Kouhestani; M.A.A Mokhtari; M Feizi
Abstract
The Aqkand area is located at 48 km north of Zanjan and is a part of the Tarom subzone within the Western Alborz-Azerbaijan structural zone. Acidic rocks exposed in this area consist of Oligocene rhyolite-rhyodacite, perlite, pitchstone and ignimbrite. Rhyolites and rhyodacites are exposed as domes and ...
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The Aqkand area is located at 48 km north of Zanjan and is a part of the Tarom subzone within the Western Alborz-Azerbaijan structural zone. Acidic rocks exposed in this area consist of Oligocene rhyolite-rhyodacite, perlite, pitchstone and ignimbrite. Rhyolites and rhyodacites are exposed as domes and lava flows. Perlites are located at the lower parts of the rhyolitic-rhyodacitic domes. Geochemical investigations indicate calc-alkaline nature along with magmatic arc affinity for the studied rocks. These rocks are characterized by LREE-rich patterns with high LREE/HREE ratio and distinctive negative Eu anomaly. Positive anomalies of Rb, Pb and Th on the spider diagrams suggest continental crust involvement in the genesis and evolution of the parental magma. Based on tectonic setting discrimination diagrams, Aqkand acidic rocks are plotted in the post-collision tectonic setting. In overall petrographic, petrologic and geochemical evidence demonstrate that during the final stages of the continental collision, the thickened sub-continental lithosphere in the Alborz was delaminated and replaced by hot asthenospheric mantle. Rapid upwelling of hot asthenosphere gave rise to the partial melting of sub-continental lithosphere which produced the Oligocene basaltic rocks of the study area. Emplacement of basaltic magma in the upper part of the continental crust led to the partial melting of the crust and generation of the acidic magmas. Rapid cooling of acidic lavas led to the generation of glassy rocks such as obsidian which are changed to perlite in contact with meteoric and warm waters.
A. Kamali; M. Moayyed; M. Jahanbakhsh Ganjeh; H. Pirooj; M. Jokar; A. Ameri
Abstract
The studied area is located at southeast of Myaneh, in east Azarbaijan province. The tourism industry, especially geotourism is a new approach for improving of coexistence of human and nature, in order to make economic benfites is nowadays very important for local development. By evaluation of natural ...
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The studied area is located at southeast of Myaneh, in east Azarbaijan province. The tourism industry, especially geotourism is a new approach for improving of coexistence of human and nature, in order to make economic benfites is nowadays very important for local development. By evaluation of natural potential of areas with direction, planning and physical developments in the direction of tourisms industry and absorption of tourist especially in national and international scale, can help to provide job opportunities.This study, by investigating a small sample of geotourism potential of the country, tries to help a new approach towards the natural resources of the country. Threfore in this study, for investigation and evaluation of geotourism potentials of the study area, the taget function and traversing the geomorphological and geological features are carried out. In the model, using advantage coefficient (dij), it is possible to allocate tourism potential preferential to different locations and announce the location with highest advantage coefficient as top tourism localities. This research is a case study for using advantage coefficient model for the Qaflankuh area in east Azarbaijan. This area has unique, intact historical and natural features that can attract tourists. The variety of rocks in the area (andesite, basalt, rhyolite, ignimberite, fissure dykes, agates, perlite, faults, agglomerates, volcanic breccias, and volcanic bomb) has provided spectacular sights for every geosciences and geography. Qaleh Dokhtar and Pol- Dokhtar are example of historical-cultural sites. The results of this study, introduces the study area as a scientific geopark and as a natural history museum.
