Abstract
Monocline and strike-slip faults are at the Moniwa and Aobayama hills, west of Sendai City area. The monocline trends to the northwest and southeast, and constitutes the Kagitori-Ayashi Line. The monocline is an asymmetric concentric fold formed by northeast-southwest compression, after the deposition of the Pliocene Sendai Group. The north-south trending Aoba Fault Zone crosscuts this monocline. The fault zone contains the Aoba Eastern Fault, Aoba Central Fault, and Aoba Western Fault. The Aoba Central Fault and Aoba Western Fault are dextral faults with a relative uplifting component of their eastern sides, and the Aoba Eastern Fault is a sinistral fault with a relative uplifting component of its western side. The Aoba Fault Zone is a northern extension of the Futaba Fault, and reactivated under the northeast-southwest compression as dextral faults and under later northwest-southeast compression as a sinistral fault.
