Document Type : Original Research
Department of Earth Sciences, Chalus Branch, Islamic Azad University, Chalus, Iran
The development of knowledge of morphotectonic and seismotectionic during the past 10 years in the country reveals containing valuable information about the history of activity of a fault. These surveys in addition to reveal the activity of faults, they can be used in estimating the movement and rate of fault activity and detection of motion of shells blocks. This paper aims to identify fault in the sea and coastal-foothill areas and possibility of its activation and subsequent of marine hazards including tsunami and liquefaction, and to achieve this goal, it was investigated the structure status of region, coastal fractures and sea context, the shell motions and the status of stress field. The study region is semi western of south of Caspian and mainly in the range of Astara fault and Caspian fault and outcome of studies conducted is based on geophysical data and remote measuring in coastal- foothill part and then on the sea context. The result of data indicates that the draught faults are extended and their activity is likely and subsequently we will have producing massive waves (tsunami) caused by the fault activity. Studies have shown the regions of coasts of Noshahr and Chalus, Ramsar and Tonekabon in Mazandaran and coasts of Rudsar- Langrud and Lahijan in Gilan province has the highest risk of drowning and its reason can be heterogeneous topography of various depths in the sea in the cities.