An adit (from Latin ''aditus'', entrance)〔 is an entrance to an underground mine which is horizontal or nearly horizontal,〔Paul W. Thrush, 1968, ''A Dictionary of Mining, Mineral, and Related Terms'', US Bureau of Mines, p.12.〕 by which the mine can be entered, drained of water,〔R. W. Raymond, 1881, ''Glossary of Mining and Metallurgical Terms'', American Institute of Mining Engineers, p.3.〕 ventilated, and minerals extracted at the lowest convenient level. Adits are also used to explore for mineral veins.〔
Adits are driven into the side of a hill or mountain, and are often used when an ore body is located inside the mountain but above the adjacent valley floor or coastal plain. In cases where the mineral vein outcrops at the surface, the adit may follow the lode or vein until it is worked out, in this case the adit is rarely straight. The use of adits for the extraction of ore is generally called drift mining.
Adits can only be driven into a mine where the local topography permits. There will be no opportunity to drive an adit to a mine situated on a large flat plain, for instance. Also if the ground is weak, the cost of shoring up a long adit may outweigh its possible advantages.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
| 翻訳と辞書 : 翻訳のためのインターネットリソース|
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.