• A5: Dam of Power Station No. 2

Horomankyo Area

Geological Site


Dam of Power Station No. 2

Dam of Power Station No. 2

Water held back by this small dam on the Horoman River is sent to the adjacent Power Station No. 2 (Geosite A1) via underground water pipes.

Dunite, a type of peridotite consisting largely of olivine, is found on the riverbank immediately downstream of the dam. This rock forms when molten olivine crystallizes, and the type found here contains gigantic olivine crystals measuring more than 10 centimeters across. It forms layers around 15 centimeters wide with harzburgite on both sides.

*Individual access is restricted. For more information, contact the Commerce, Industry and Tourism Department of the Samani Town Government (E-mail apoi.geopark@festa.ocn.ne.jp).