| Abstract |
The target depth of geothermal energy development has increased in many countries. During the drilling and logging of deep wells, many problems have occurred due to severe conditions related to increasing well depth and rising temperatures and pressures. Developers concerned with drilling and logging of wells probably have encountered similar problems and have had similar experiences in solving them. Therefore, it is very useful to compile and exchange these experiences. Cooperative investigations on drilling and logging technology under the IEA Deep Geothermal Resources task started in March 1997. Five research programs related to drilling and logging technology were proposed by the USA, Mexico, and Japan for the mutual exchange of information. Drilling and logging data from deep geothermal wells in several countries, obtained from published papers, have been stored in the database in the DGR web site. This paper outlines the status of geothermal drilling technology experienced by the participants, based on published reports, and a future technological proposal on drilling and logging for DGR development. |