 In depth the lesser fractures are not tilled and are therefore less conspicuous. The veins of the district, both copper and silver veins, belong to three distinct systems. The oldest lodes have a general east-west course, the Parrot, Anaconda, and Syndicate...  Bulletin of the United States Geological Survey - Seite 175von Geological Survey (U.S.) - 1903Vollansicht - Über dieses Buch
 | 1903 - 988 Seiten
...disintegrated granite between, soft enough to yield to the pick. In depth the lesser fractures are not tilled and are therefore less conspicuous. The veins of the...enormous development work expressly made to develop the structure and continuity of veins for the various lawsuits between the mining companies. The silver... | |
 | Samuel Franklin Emmons - 1903 - 462 Seiten
...Syndicate lodes being examples. Another set of fractures has a northwest-southeast course, and lias displaced the earlier veins. A still later set has...enormous development work expressly made to develop the structure and continuity of veins for the various lawsuits between the mining companies. The silver... | |
 | Arthur Lakes - 1905 - 456 Seiten
...REGION. MONTANA. r first two systems, says Mr. H. Weed, are heavily mineralized, the last shows a little ore broken off from earlier deposits and included in the fault debris. The copper veins were at first worked as silver veins. The surface gossan was soon replaced in depth-... | |
 | Walter Harvey Weed - 1907 - 408 Seiten
...with rotted or disintegrated granite between, soft enough to yield to the pick. In depth the lesser fractures are not filled and are therefore less conspicuous....earlier deposits and included in the fault de•bris. The silver veins surround the copper lodes on the north, west, and southwest. Their course and geologic... | |
 | Walter Harvey Weed - 1907 - 398 Seiten
...copper and silver veins, belong to three distinct systems. The oldest lodes have a general cast-west course, the Parrot, Anaconda, and Syndicate lodes...earlier deposits and included in the fault debris. The silver veins surround the copper lodes on the north, west, and southwest. Their course and geologic... | |
 | Walter Harvey Weed - 1907 - 408 Seiten
...first two systems are heavil mineralized ; the last shows a little endogenous ore, but the materia mined is mainly the ore broken off from earlier deposits and included i the fault debris. The silver veins surround the copper lodes on the north, west, and southwest. Their... | |
 | Eugene Thomas Hancock - 1910 - 284 Seiten
...formed later. The last, or northeast-southwest, system of fractures shows a. little ore, but the mineral mined is mainly the ore broken off from earlier deposits and included in the fault debris. The ore-bodies have also frequently been displaced by either strike or dip faults. The strike faults... | |
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