Using Airborne Magnetometer Data and Geomorphic Evidence to Study the Hidden Fault Path in Khorram Abad Plain

Khorram abad plain is located in the folded Zagros region and has secondary and main faults. Since these hidden faults are possible using geophysical data and geomorphic evidence, so in this research, the purpose of this evidence is to investigate and identify the path along the Khorram abad fault below the Quaternary sediments in the Khorram abad plain. In order to achieving these goals, airborne magnetic taken data from 1975 to 1977 for Khorramabad area were gotten from geology organization. After correcting, aligning micro aligning and exerting the common corrective filters on these data in the Oasis montaj 6.4.2 software and creating database for them in the software, geomorphology evidence and elevation changes were also used to prove the existence of a hidden fault in Khorram abad plain. The results showed that Khorram abad fault after crossing the mountain Yafteh and the Sefid koh, inter the Khorram abad plain and under the quaternary sediments extends along that line. The presence of linear magnetic anomalies in the next section of the obvious Khorram abad fault, geomorphic evidence such as stacks and alluvial fans and altitude variation in survey sections, Prove that this fault is hidden. This line with the trend of northwest - southeast in the central part of the study area, It passes about 38 km from the distance of about 3 km from the south of Khorram abad city.