Tectonics
M. Kouhpeyma; M. Talebian; L. Chen; A. Ghods; M. Ghorashi
Abstract
The Kopeh Dagh and Binalud-Alla Dagh mountains are important structural elements located in the northeastern boundary of Arabia-Eurasia collision zone. Due to existence of large cities with a long history of civilization, there is a relatively rich body of data on historical seismicity in this area. ...
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The Kopeh Dagh and Binalud-Alla Dagh mountains are important structural elements located in the northeastern boundary of Arabia-Eurasia collision zone. Due to existence of large cities with a long history of civilization, there is a relatively rich body of data on historical seismicity in this area. Nonetheless, little adequate instrumental seismic data were available prior to this study. In this paper, we utilized the temporary China-Iran local seismic network data deployed in the area for 13 months. Based on this data, we determined 37 focal solutions through first motion polarity approach suggesting a combination of strike-slip, reverse and normal mechanisms. There is a significant concentration of epicenters and focal mechanisms around the eastern Alborz - Kopeh Dagh boundary along the Atrak River. The southern and western boundaries of the Binalud Mountains also show relatively high seismic activities. The Local magnitude (ML) of the events ranges from 3.5 to 4.9 with depths of up to 20 km, mostly concentrated at ~10 km. The principal stress axes and slip vectors obtained from the focal mechanisms agree well with kinematic state of main faults and tectonic regime of the area, confirming the seismogenic nature of these faults. In addition, they are consistent with right-lateral component of slip along thrust faults in eastern Kopeh Dagh and Binalud and both laft- and right-lateral motions in the central Kopeh Dagh.
R. Akbari Jonosh; M. Ghorashi; Hasan. A. Babaei; M. Nakhaei; M. Pourkermani
Abstract
Considering Iran’s situation in drought risk area, in this study karstic waters are investigated. The study area is located in central of Iran, Semnan province. Several factors are important in Karstification and formation water resources in carbonate, among them important are petrology, topography, ...
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Considering Iran’s situation in drought risk area, in this study karstic waters are investigated. The study area is located in central of Iran, Semnan province. Several factors are important in Karstification and formation water resources in carbonate, among them important are petrology, topography, climate, geomorphology and hydrogeology are pointed out. In this research, the role of structural factors in the development of karstic water resources in Semnan province has been studied. firstly, information layers of each factor prepared. For example, tectonic elements, includes maps: lineament density, faults length density, faults intersection density and density distance from faults making use geological maps and processing of satellite images. Information layers analyzed in the geographical information system (GIS), Expert Choice Software making use geostatistical methods. In this study, multi methods like analytic hierarchy process (AHP) and Fuzzy analytic hierarchy process (Fuzzy AHP) used in study of karstic water resources.
