Abstract

Sabalan, with an elevation of 4,811 meters, is the second-highest mountain located in the Alborz mountain range in northwestern Iran. Although it is an inactive stratovolcano, the overall system of faults around the Sabalan peak can be considered as two common groups of linear and arcuate faults. Faults with the linear structure are mainly observed along with the NW-SE and N-S directions at the southern part of Sabalan. Arcuate faults around the Sabalan  volcano  are  almost  coincided  with  the  crater  of  the  volcano  and  have  led  to  the  penetration of volcanic masses. In this study, magnetotelluric data modeling was performed on one profile (“namely the MM profile”). The profile includes both types of fault systems in the region. By assessing and interpreting the resistivity section of the MM profile by 2D  magnetotelluric  data  inversion,  we  have  clearly  detected  the  faults  by  features  such  as  displacement  and  sudden  changes  in  resistivity  anomalies  forming  conductive  zones  with low resistivity anomaly along with the profile. The MM profile has almost continuous conductive anomaly (<30 Ω-m) between elevations of 1000 to 3000 m except in the eastern side, where a resistive block is found from the surface down to lower depths. Eight faults were detected across the MM profile. Our final represented geology section is consistent with actual observations and 2D magnetotelluric data inversion and prior studies.

Keywords

magnetotelluric, stratovolcano, fault detection, inversion, resistivity section