Bulletin - United States Geological Survey, Issue 660

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Page 58 - Harder, EC— Manganese deposits of the United States, with sections on foreign deposits, chemistry, and uses: US Geol.
Page 148 - ... coming into the main valley at a right angle on its north side. The main valley was seen continuing north-westward some twenty miles beyond this point. Above the portage the valley varies from a quarter of a mile to a mile in width, and as the grade is heavy, the river rushes through it as an almost continuous heavy rapid, which does not freeze over. Only a narrow margin of ice was found along the shore, and over it travel was slow and difficult. " Where the main stream issues from the...
Page 99 - The ore is a brown hematite, interbedded in the rock in irregular pockets, from a few inches to a foot or more in thickness. The...
Page 93 - River, several small pits have been sunk for manganese on the summit of the mountain, and a tunnel forty feet long has been run into the north side about twenty-feet below the summit. The gray novaculite forms the crest of the ridge and the siliceous shale comprises the slopes. The tunnel has reached the novaculite through the shale. The manganese is in the form of a crystalline pyrolusite, mixed with a hard, massive ore, and occurs in irregular nests, from a quarter of an inch to three inches in...
Page 98 - The manganese-bearing deposit varies from 1 to 2 feet in thickness and dips almost vertically. The ore, however, composes only a small part of this and usually occurs as thin seams and pockets from a fraction of an inch to over 2 inches in thickness, scattered irregularly through the rock. Occasionally, however, the ore widens out locally into pockets, of somewhat larger size. Sometimes the ore disappears altogether or- is represented only by a stain in the rock, but widens out again at irregular...
Page 37 - Rogers, HD Description of the geology of the state of New Jersey. 1840. QE141 1835. 2707 Report on the geological survey of the state of New Jersey. 2d ed. 1836. QE141 1835. 2708 Vermenle, CC Report on watersupply. 1894. (New Jersey. Geological survey. Final report, v. 3 ) QE141 1888.
Page 17 - ... red to reddish black, is formed. This is the more common phase, while the crystalline, specular form which results from pronounced recrystallization is more local in its occurrence. Some of the hard, red Jaspilite shows oolitic texture. In places in the Cuyuna district there is a very hard, dense, siliceous, ferruginous chert to which the term jasper is sometimes applied. This rock, however, varies in color from brown or reddish brown to black, and is simply a very siliceous ferruginous chert....
Page 58 - ... geologists ; consequently, but few have been described. The writer recently received a number of specimens of limestone from the lowest marine Jurassic beds of Washington County, Utah, which upon study prove to represent algal deposits. The algal colonies have formed calcareous masses which range In size from a fraction of an inch to over a foot in diameter. They are spherical or egg shaped and have a concentric structure which becomes distinct on weathering. The rock Is light yellowish brown...
Page 15 - ... are believed to be the original rocks from which the iron-bearing formation of the Cuyuna range in its various phases is largely derived. Such rocks have been reported from many parts of the district, having been found in the deep drilling.
Page 5 - ... igneous metamorphosed rocks interlayered with each other in beds and lenses and usually having steep dips due to extensive folding, (2) igneous rocks intruded into the metamorphosed rocks subsequent to their metamorphism and deformation, and (3) younger rocks which lie horizontally on the eroded surfaces of the rocks of the other two classes.

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