A Khaiatzadeh; A Abbasnejad
Abstract
Multi-Criteria Decision Making methods have progressed extensively in the past decades and have been applied in various disciplines. Application of them in different fields of geology, especially in assessment of geological hazards which are usually multi-criteria in character, can be very helpful. Studies ...
Read More
Multi-Criteria Decision Making methods have progressed extensively in the past decades and have been applied in various disciplines. Application of them in different fields of geology, especially in assessment of geological hazards which are usually multi-criteria in character, can be very helpful. Studies such as the present study will widen their uses in various fields of geology. Volcanic eruptions in the past centuries attest that stratovolcanoes are more hazardous than other volcanoes and their activity may be disastrous. Hence, in this study, multi-criteria decision making methods of EN-SAW and ANP have been applied to assess and rank the reactivation hazard of Iranian stratovolcanoes (Damavand, Taftan, Bazman, Sahand, Sabalan, Bidkhan and Mesahim) as a case study. So, firstly, the criteria useful in their hazard assessment were selected which include the age of the latest eruption, the presence or absence of tectonic regime creating the volcano, the status of post volcanic activities (e.g. hot springs) and the extent of erosion. Afterwards, they were scored by several experts and lastly, by applying EN-SAW and ANP methods and using Super Decision software, the reactivation hazard scores of these volcanoes were determined and they were ranked. In both these methods, the Damavand volcano ranked first. So, its reactivation potential is higher than other ones and must given the first priority, its threats must be evaluated, its hazard zoning maps should be prepared and (as a kind of monitoring) a seismic station can be established. According to the applied methods, Bazman, Taftan and Sablan volcanoes acquired nearly the same scores. So, ranking after Damavand and it is recommended that they be considered as semi-active (dormant) volcanoes. The condition for Sahand volcano is not clear. However, Bidkhan (in Bardsir town of Kerman) and Masahim (North of Shahrebabak town) both acquired very low scores. So, they are considered as inactive and are not hazardous.
M Sheban; F Ghaemy; A Abbasnejad; F Ghaemy
Abstract
Neotectonics that is a major factor of landform development in tectonically active regions has significantly affected fluvial systems and mountain-front landscapes in the Behabad area of the Central Iran Zone. To assess tectonic activities in the area, we analyzed geomorphic indices including the mountain-front ...
Read More
Neotectonics that is a major factor of landform development in tectonically active regions has significantly affected fluvial systems and mountain-front landscapes in the Behabad area of the Central Iran Zone. To assess tectonic activities in the area, we analyzed geomorphic indices including the mountain-front sinuosity (Smf), stream-gradient index (SL), valley floor width–valley height ratio (Vf), drainage basin shape (Bs) and drainage basin asymmetry (Af). These indices were combined to yield the relative active tectonics indices (Iat). Based on Iat values, the study area was divided into four parts: Class 1 (very high relative tectonic activity, 1.52% in area), Class 2 (high, 68.58%), Class 3 (moderate, 20%), and Class 4 (low, 9.9%). The results are consistent with field observations on landforms and geology. The active tectonics indices and geomorphological evidences indicate that the tectonic activity rate in the studied area is predominantly moderate to high.
