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50 feet alluvium auriferous azurite basin beach bed rock belt bench gravels body bornite Bull Bulletin calcite cassiterite cents chalcocite chalcopyrite Chitina Chitistone limestone claims coal considerable Copper River cost country rock crosscut deposits depth developed dikes diorite ditch Drainage area dredge drift drill east elevation exposed Fairbanks district fault feet deep feet long Fortymile galena geologic Glacier gold granite greenstone ground gulch igneous inches intrusive investigations Island July Kasaan Peninsula Kennicott Kennicott River Kotsina River Kougarok limestone localities located lode magnetite marble masses material metamorphic mining Moffit Mountain mouth Nizina Nome occur open cut operations placer mining places porphyry portion present production prospecting pyrite quartz quartz veins region reported schist season Seward Peninsula shaft shales side southeastern Alaska square miles stream strike sulphides surface Survey thickness tributary tunnel U. S. Geol valley width Yukon zone
Seite 298 - A reconnaissance of the Cape Nome and adjacent gold fields of Seward Peninsula, Alaska, in 1900, by AH Brooks, GB Richardson, and AJ Collier. In a special publication entitled "Reconnaissances in the Cape Nome and Norton Bay regions, Alaska, in 1900,
Seite 128 - SCHRADER, FC, and SPENCER, AC The geology and mineral resources of a portion of the Copper River district, Alaska.
Seite 163 - ... azurite veins extend still farther in that direction. The ore, as it shows on the surface, therefore, extends northeast and southwest along the strike for a distance of 400 feet. The thickness, however, is more indefinite, but the very rich ore, with its included limestone, as seen at the surface, has a width of approximately 25 feet, although the thickness of ore sufficiently rich to be mined may be greater.
Seite 299 - No. 10, 1902, 68 pp. A reconnaissance in northern Alaska across the Rocky Mountains, along the Koyukuk, John, Anaktuvuk, and Colville rivers, and the Arctic coast to Cape Lisburne, in 1901, by FC Schrader and WJ Peters. Professional Paper No. 20, 1904, 139 pp. (Out of stock; can be purchased of Superintendent of Documents for 40 cents.) Coal fields of the Cape Lisburne region, by AJ Collier.
Seite 125 - Natural cements are produced by burning a naturally impure limestone, containing from 15 to 40 per cent of silica, alumina, and iron oxide, at a comparatively low temperature, about that of ordinary lime burning. The operation can therefore be carried on in a kiln closely resembling an ordinary lime kiln.
Seite 298 - No. 314, 1907, pp. 187-204. The Yukon-Tanana region, Alaska; description of the Fairbanks and Rampart quadrangles, by LM Prindle, FL Hess, and CC Covert. Bulletin No.
Seite 83 - Juneau gold belt, which has been irregularly traced along the mainland from Windham Bay to a point 10 miles north of Berners Bay, where it enters Lynn Canal. It has a total length of 120 miles and a width of less than 10 miles. In this zone gold is the dominant metal present and occurs in varying amounts disseminated with sulphide minerals in bands of schistose rock 10 to 60 feet wide; in altered diorite dikes, where it is associated with stringers of quartz ; and in quartz veins, 1 to 10 feet wide,...
Seite 118 - ... diabase, striking northeasterly and much altered and faulted, were observed intersecting the marble beds. Apparently these dikes antedate the metamorphism of the limestone and therefore the intrusion of the granite. They are, however, but a foot or two in width and not sufficiently numerous to affect the value or expense of quarrying the marble. In the present opening at the quarry only one dike is exposed. Both surface cracks and slipping planes are present in the surface exposures of the marble,...
Seite 24 - Cold Bay have been collected by the writer. They were obtained by skimming the petroleum from the surface of the pools of water where it was continually rising from the bottom of the pool. An effort was made to obtain as much of the fresher oil as possible. Vegetable and earthy impurities were removed by straining through coarse cloth. Water could not be entirely removed. Oil for lubricating purposes at the neighboring wells is obtained from these pools in this manner. The fresher oil is dark green....