Professional Paper - United States Geological Survey, Ausgaben 109-110The Survey, 1919 |
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Alaska alluvial cones altitude amount Arctic aufeis bank basalt beach beds blocks boulders Cambrian Campito canyon Cerro Gordo coast Colville Creek Dease Deep Spring Valley deposits depth dikes diorite earth east epoch erosion evidence exposed exposures fault feet thick flank Flaxman Island Fork formation formed fossils freezing frost Geology glacial glaciers granite gravels ground ice horizontal hornblende ice wedges Idem inches Inyo Range layers limestone locality lower mass material meters miles moraines mounds Mount Whitney Mountains observed occur Okpilak orthoclase Owens Lake Owens Valley Peak Pine Plateau Point Barrow porphyry probably quadrangle quartz monzonite quartzite region rhyolite ridges River rocks Sadlerochit Saline Valley sand sandstone scarp Schergin schist seen shaft shales Sierra Nevada silt slope snow stream summit surface tains temperature tion Triassic tundra U. S. Geol upper vertical west side writer zinc
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Seite 109 - ... The defendant pleaded that Scott, being a negro, and born of slave parents, could not be a citizen of Missouri, and hence could not be a party to a suit in the United States courts. The plea was overruled, but on other grounds Scott's claim to freedom was denied, and judgment rendered against him. The case was then appealed to the United States Supreme Court, where it was twice argued, in February and December, 1856. The decision was rendered March 6, 1857. Chief Justice Taney delivered the opinion...
Seite 9 - ... Canning River region, northern Alaska, by E. de K. Leffingwell. 1919. 251 pages, 35 plates, 33 text figures. Prior to the explorations whose results are here set forth the Canning River region of Arctic Alaska was practically unknown except as to its larger geographic features. The region as a whole presented an almost complete hiatus in the scientific knowledge of Alaska, and Mr. Leffingwell has performed a valuable service in mapping and describing its geography and geology. During the 10 years...
Seite 119 - The veinlets range from a fraction of an inch to several inches in thickness. The larger veinlets are quartzose and contain coarse orthoclase, muscovite, and fluorite, and are therefore pegmatitic in composition and appearance.
Seite 109 - the whole management of the works is rather calculated to create the suspicion that the proper composition of the charge is not understood. It is certain that either by an addition of iron oxide to the present charge, or by omitting the addition of the quartzose silver ores altogether, far better results might be obtained than at present." " These suggestions seem to have borne some fruit, for the old slag dumps, as sampled by the present management of Cerro Gordo, show a content of not over $5...
Seite 232 - ... where it looked as if a detached fragment of ice had been and had been melted out, leaving its mold in the clay quite perfect. " In other places the ice was penetrated with deep holes, into which the clay and vegetable matter had been deposited in layers, and which (the ice melting away from around them) appeared as clay and muck cylinders on the ice-face.
Seite 236 - ... alluvial deposit, such planes of weakness being generally determined by the presence of thin bands of silt or fine sand. As any outlet to the top is now permanently blocked, the water is forced along this plane of weakness, and there freezes; and thus the horizontal extension of the sheet of ice is begun. While thus increasing in extent, the ice also increases in thickness by additions from beneath, until it has attained a sufficient thickness so that its bottom plane is beyond the reach of the...
Seite 236 - The mode of formation of these underground sheets of ice is therefore somewhat as follows: Water, issuing from the rock beneath a layer of alluvial material, rises through the alluvium, and in summer spreads out on the surface, tending to keep it constantly wet over a considerable area. In winter, if the flow of water is large, and the surface consists of incoherent gravel, the water will still rise to the surface, and there form a mound of ice. If, on the contrary, the flow from the spring is not...
Seite 236 - ... is beyond the reach of the low atmospheric temperature above; after which it continues to increase in extent, but not in thickness or depth. With the advent of the warm weather of summer the growth of the crystosphene ceases, but the cold spring water which continues to rise up beneath it has very little power to melt it, and its covering of moss or muck, being an excellent non-conductor of heat, protects it from the sun and wind, and prevents it from thawing and disappearing. Thus at the advent...
Seite 148 - Archean gathering grounds to the east poured westward through the gaps and passes in the eastern flanking ranges of the Rocky Mountains until it reached the barrier formed by the main axial range, when, being unable to pass this, it was deflected to the northwest in a stream from 1,500 to 2,000 feet deep down the valley of the Mackenzie and thence out to sea.
Seite 44 - Owenyo consists in the main of massive, grayish, crystalline to compact limestones. The 2-foot basal bed is a blue-gray compact limestone, fossiliferous from the contact and carrying irregular lenses and stringers of sandstone whose grains were apparently derived from the Reward below. Here and there through the Owenyo, particularly in its uppei third, are layers carrying rounded chert pebbles.