| Title | Conduction Dominated Geothermal Regime in the Sengan Region, Northeastern Honshu, Japan |
|---|---|
| Authors | Matsubayshi, O. |
| Year | 1983 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Exploration; Japan; Honshu; Sengan Region; Thermal Conductivity; Temperature Gradients; Rhyolitic Rock; Self Seating; Alteration Minerals; Subsurface Hydrology; Hachimantai Volcanic Region |
| Abstract | The Sengan Region, one segment of the backbone range of Northeastern Honshu, has a very unique thermal structure. Heat flow determined in holes with depths 200 to 500 m is higher than 120 mWm-2 anywhere within the region of approximately 40 km (E-W) x 50 km (N-S) mostly covered with young volcanic risks thicker than 500 m. In contrast to other Japanese geothermal target areas such as Hohi, Kyushu, the Sengan Region is characterized by the absence of shallow temperature inversions indicating transient horizontal water flow or thermal convection, except for the immediate vicinity of the known reservoirs under exploitation. This pattern may be related to the characteristic mode of volcanic history of the region. |