Fig. 7. East-west cross-section of the final inverted model (Fig. 5a) at north-south distances of (a) −600 m, (b) 0 m and (c) 600 m. Locations of the MT stations are also mapped and shown at the surface along with the hot spring locations.
4. Conclusion
A 3-D resistivity structure determined from a small number of MT stations sparsely distributed around the Mae Chan geothermal area provides very useful information to assess the potential for a geothermalpowerplant.IntheMaeChanhydrothermal system,hot fluid heated from the deeper granitic batholith, identified as high resistivity feature R, is stored in the fractured and weathered granite and the sedimentary rock indicated by two conductive zones C1 and C2. A fracture in the damaged zone of the fault (shown as a resistivity contrast) allows the pressurized hot fluid to reach the surface. Since the temperature of the Mae Chan hydrothermal system does not seem to be high, we propose the development of small-scale geothermal power plants over the two zones C1 and C2. Further detailed investigation with more MT coverage along with deep well drilling may be necessary in order to assess the potential to build a larger scale geothermal power plant in the area.
Acknowledgements
The authors would like to thank the Thailand Research Fund (RSA5780010) and the Thailand Department of Energy Development and Efficiency (DEDE) for the support and permission to publish this study. We would like to thank Miss. Patchawee Nualkhow for her dedicated participation during the field work. Mr. Puwis Amatyakul would like to thank the Development and Promotion of Science Talents project (DPST) for a scholarship. The authors appreciate the suggestions and collaboration of Mr. Suebsak Solkosoom, Mr. Tawan Sukho and Mr. Adisak Choosuk. We also would like to thank Dr. Kurt Strack of KMS technologies – KJT Enterprises Inc. for the MT instruments used in the field survey. The comments of an anonymous reviewer, Dr. Erika Gasperikova and the Editor are greatly appreciated.