| Title | Tracer Response of Injection Test in Hot Spring Fluid Layer at Minami-Izu Geothermal Field, Shizuoka, Japan |
|---|---|
| Authors | Yanagisawa, Norio; Matsuyama, Kazuo; Takeda, Yasuto; Tomita, Kazuo; Yasukawa Kasumi; Sakaguchi, Keiichi |
| Year | 2013 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Hot spring; tracer; injection; fault; return ratio; optical fiber; Minami-Izu |
| Abstract | Tracer test is carried out to survey flow properties in high temperature hot spring fluid layer about 150 meter depth at Minami- Izu geothermal field, Shizuoka, Japan. About 500g of uranine was used for tracer and injected on 16 September, 2012. We monitored tracer appearance at 5 wells using optical fiber system and lab spectrometer. After 9 hours from tracer injection, first tracer appeared at Daigaku-yu (K-13) well about 70 meter distance SSE from the injection well along large fault. The tracer concentration rapidly increased and peaked at three days after injection. And the return ratio is estimated about 30%, similar to several EGS test fields. After 5 days, tracer appeared at a monitoring well about 600 meter depth and this suggests flow path to deeper reservoir. In Tamagawa-yu (K-11) about 150 meter from injection well, tracer appeared in early October. This tracer response shows the natural flow of hot spring fluid direction to east. |