1970 Volume 20 Issue 100 Pages 182-189
The regional geological survey, which was planned for prospecting the metallic ore deposits in the 27 hopeful districts in Japan, is carried out by the Metallic Minerals Exploration Agency of Japan.
The geophysical exploration methods are employed for this regional geological survey especially in the "Kuroko" type ore deposit areas, to obtain some effective information, the structure of basement rocks and of ore-bearing horizons.
The geophysical exploration methods include gravity, seismic, sonic and other methods, the first of which is the most effective exploration method to get information of the regional geological structures such as faults, folding, doming and/or basin structures. The seismic method is used for obtaining the quantitative information about the depth of basement rocks and/or ore-bearing horizons, and the sonic exploration method is used for obtaining the same information in the near shore area.
The results of gravity and seismic prospecting in the Kita-Shimane district and of sonic prospecting in the Shimoita district are presented in this paper, which are good examples showing effective geophysical exploration methods applied to "Kuroko" deposit areas.