Fluid electric conductivity logging; Useful application for charactreization of water-conducting features

水みちの特性把握のための流体検層の有効な適用方法について

竹内 真司; 天野 健治  ; 竹内 竜史  ; 三枝 博光

Takeuchi, Shinji; Amano, Kenji; Takeuchi, Ryuji; Saegusa, Hiromitsu

Fluid electric conductivity logging (FEC logging) and other fluid logging techniques have been carried out in the deep borehole in the granite to identify water-conducting features (WCFs). Also transmissivity have been estimated from the FEC logging and compared with the one estimated from hydraulic packer testing targeted on the same WCFs. From the results of the investigations, FEC logging can be used for identification of WCFs in detail than the other fluid logging techniques. Transmissivity estimated from FEC logging can be used for the supplement for the one from hydraulic testing in the borehole without the skin effect such as due to drilling mud and/or due to drilling damage. Based on the results above, one of the efficient methods for better understanding the groundwater flow in the borehole, that is the FEC logging for identification of the WCFs followed by the hydraulic testing focusing on the identified WCFs, is addressed.