マレーシヤ国・マムート鉱山の試錐について
1971 年 21 巻 106 号 p. 179-185
詳細
1971 年 21 巻 106 号 p. 179-185
Under the contract with Overseas Mineral Resources Development Company Limited, a prospecting project by diamond drillings in the Mamut mine, Sabah, Malaysia, was carried out as a joint venture of Sumiko Consultants Co., Ltd., and Nikko Exploration and Development Co., Ltd., during the period of fifteen months from June, 1968 to August, 1969.
The project was divided into two stages, the first and the second. The outline of these stages is shown in the following table :
1 st Stage
2 nd Stage
(from June to November, 1968)
(from December, 1968 to August, 1969)
No. of holes 21 55
Total length 4, 297m 11, 424m
Drilling length per one shift 7.03m 7.95m
Core recovery 81.8% 83.0%
In pursuing the works of these stages, the following considerations were made :
Transportation : All of the drilling machines and tools were transported by the cableways because of rugged topography and thick vegetation.
Drilling Machine : High speed-type machines which have good efficiency for hard rocks were used. Diamond bits were selected carefully in accordance with the hardness of rocks.
Cutting Oil and Chemical Grout : Some amounts of cutting oil were added in circulating water in order to increase the cutting efficiency. The wall was protected from caving by chemical grout in many fractured zones.
