What people are saying - Write a review
We haven't found any reviews in the usual places.
Other editions - View all
abundance Alaska amount analyses appears average beds biotite bodies building Bull Bulletin carried cent clay coal coarse color Company considerable consists contains copper County course Creek deposits depth described dikes district east exposed extends fault feet feet thick feldspar field formation Geological gold grain granite gravels gray head hills important inches included iron Island joints known less lignite lime limestone localities lower Maine masses material measures mica miles minerals mining Mountain nearly occur opened operations origin oxide pegmatite places plant portion present probably prospects quarry quartz Railroad range region reported ridge River rock sand sandstone schist seam shale sheets shown shows side silica specimen stone stream strike structure surface Survey tests texture thick thin United upper valley vein vertical wide
Page iii - ... publications of the United States Geological Survey consist of (1) Annual Reports, (2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral Resources, (6) Water-Supply and Irrigation Papers, (7) Topographic Atlas of United States — folios and separate sheets thereof, (8) Geologic Atlas of the United States — folios thereof.
Page viii - SCHRADER, FC, and SPENCER, AC The geology and mineral resources of a portion of the Copper River district, Alaska.
Page 215 - 24. List of Marine Mollusca, comprising the Quaternary fossils and recent forms from American Localities between Cape Hatteras and Cape Roque.
Page 409 - More commonly the larger crystals will be found either in clusters at intervals through the "vein," in places connected by streaks of small crystals, or collected along one or both walls of the pegmatite, with some of the crystals partly embedded in the wall rock. Where there is a quartz streak within the pegmatite, the mica occurs on either or both sides of it...
Page 11 - When all the folios are completed, they will constitute a Geologic Atlas of the United States. A folio is designated by the name of the principal town or of a prominent natural feature within the quadrangle. It contains topographic, geologic, economic, and structural maps of the quadrangle, and in some cases other illustrations, together with a general description. Under the law copies of each folio are sent to certain public libraries and educational institutions. The remainder are sold at 25 cents...
Page 133 - They are developed mainly on the softest and most soluble rocks, along the axes of anticlines, the most enduring strata on the limbs of the folds forming the rims of the valleys. At distances of 2 to 5 miles apart openings or
Page 32 - ... the Colorado Canyon both vertically and horizontally jointed. If these are true granites and are still in contact with the rocks into which they were intruded and show genuine sheet structure the phenomenon would conclusively prove that such structure may occur independently of solar heat and load. Mr. SF Emmons similarly stated that in the Mosquito (Park) Range, in Colorado, the pre-Cambrian granite and schist are cut by horizontal joints to a depth of 50 feet below their contact with the overlying...