| Abstract |
Increasing needs and interests arise on extremely high temperature resources from supercritical or ductile regions. Some countries with volcanic activities have been running such projects, such as IDDP and DEEPEGS projects in Iceland, the DESCRAMBLE project in Italy, JBBP project in Japan, and HADES and the GNG projects in New Zealand. Exploitation of such superhot geothermal systems demands novel downhole logging tools, which can provide valuable information on the formation properties, enable inspection of a well completion, and assist in reservoir characterisation. Most borehole measurement and logging technologies used in the geothermal sector came basically from the oil industry. But higher capability or innovative technologies need to be developed to be applied in the very demanding superhot geothermal environment. The Task A2 "Measurement and Logging", set up under Working Group 13 "Emerging Geothermal Technologies" of IEA Geothermal TCP (https://www.iea-gia.org/) undertook to collect and share information on high temperature and high pressure (HTHP) logging tools, including information from service companies and their tool services around the world. On-going tool development projects was another interest of the authors, with the idea that this might help people understand how the technology is being advanced. The data are summarised in a Google Sheet and information is limited mostly from the member countries of IEA Geothermal TCP, and can be updated further by the input from other countries and companies. |