Details of the Abstract
| Title of paper | Reconstructing geothermal geological models by combining geophysical, geochemical and geological studies in Tatun volcanoes area, Northern Taiwan |
| List of authors | Jian-Cheng Lee, Chien-Chih Chen, Hideaki Hase, Hsin-Hua Huang, Cheng-Horng Lin, Shenrg-Rong Song, Yi-Chia Lu, En-Chao Yeh, Gong-Ruei Ho, Chuang-Hsiang Mu, Yu-Chang Chan, Li-Wei Kuo, Yue-Gau Chen, Sun-Lin Chung |
| Affiliation(s) |
Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, Department of Earth Sciences National Central University, Chungli, Taiwan, Geothermal and Energy Research & Development (GERD) Co., LTD., Tokyo, Japan, Institute of Earth Sciences, Academia Sinica, Institute of Earth Sciences, Academia Sinica, Department of Geosciences, National Taiwan University, Taipei, Taiwan, National Central University, National Taiwan Normal University, Taipei, Taiwan, Academia Sinica, Academia Sinica, National Central University, Centre of Environmental Change Research, Academia Sinica, Taipei, Taiwan, Institute of Earth Sciences, Academia Sinica |
| Summary |
In this study, we conduct a multi-disciplinary study, including geophysics, geochemistry, and geology, with help of tens of exploration wells, to reconstruct a geothermal geological model at the shallow 5 km, for a geothermal exploration project in the Tatun volcano area, northern Taiwan. Our reconstructed geological profiles show that the Tatun volcanoes have a ~1-2-km thick of lava flows, erupted on the frontal area of the 6-8-km-thick fold-and-thrust Miocene sedimentary rocks. The seismic velocity imaging indicates a likely magma reservoir of high anomaly of Vp beneath the Tatun at the depths of 8-15, with an estimated volume of ~250-300 km3. Incorporating the regional geology with the newly acquired magnetotelluric (MT) results, when it comes to geothermal reservoir, we found three horizontally-seated low-resistive layers at different depths, which we tend to interpret as possible “cap rocks”. The underlying high-resistive zones are interpreted as potential geothermal reservoirs: 1) near-surface reservoir at depth of <200 m beneath surface deposits; 2) main shallow reservoirs at the depth of 200-500 m (downhole temperature of 150-250°C), covered by low-resistive volcanic layers (possibly clay-rich altered rocks); 3) deeper reservoirs at the depth of ~ 1-1.5 km, seemingly in the uppermost basement of quartz-rich sandstone, underneath low-resistive lobs. At least four high micro-seismicity zones with cylinder shape are interpreted as conduits of hot fluid derived from deep over-pressured zones, either along the frontal thrust of the Jinshan fault (at the depth of ~2 km), or the outer edge of the fluid saturated magma reservoir around 4-6 km depth, which is also of potential for “super hot geothermal” exploration. |
| Session Keyword | 3.0 EM methods for exploration (geothermal, mineral resources, etc.) |
| File upload |
3.0_reconstructing_geothermal_lee.pdf
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