Potentially active faults in central Mongolia

The activity of the Ereen Uul fault and the Sanglin Dalai Nurr fault in central Mongolia has not been studied in detail. The Erren Uul fault is a normal fault located 45 km southeast from Harhorin and the Sanglin Dalai Nurr fault is a right-lateral strike-slip fault located 30 km south of Harhorin next to the Hangay Mountains. Remote sensing and field observations were used to refine a map by the Mongolian Geologic Survey at a scale of 1:1,000,000 to a scale of 1:100,000. This new map covers an area of 8,072 km2 . The basin asymmetry factor, stream length-gradient index, and hypsometric curves were developed for basins adjacent to these faults. These geomorphic indices along with the refined map were used to conclude that the Ereen Uul and Sanglin Dalai Nurr faults are active.