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anorthosite Archean augite basal basin beds border bowlders Cambrian carbonate Carboniferous character classification clay coast conglomerate County Cretaceous crystalline dacite debris deposits diabases district drainage drift drumlins elevation englacial erosion evidence feet flows formation fossils gabbros Geol Geological Survey geologists glacial epoch glacier gneiss granite gravel Huronian ice epochs ice-sheet iron and manganese Jour Keweenawan Lake Superior later Laurentian limestone Lower Huronian Malaspina glacier manganese margin mass material miles mineral moraine mountains observed occur ocean Ohio origin osar oxide paleolithic Paleozoic peneplain plagioclase plateau portion pp.—Bull pp.—Geol pp.—Proc pre-Cambrian precipitation present probably pyroxene quartz quartzite region ridges river rocks sand sandstone schists sedimentary sediments shore silt Silurian slope Soc'y species specimens stones strata streams structure subglacial sulphide surface terraces Tertiary thickness tion Triassic tunnels U. S. Nat unconformity Upper Huronian valley volcanic
Page 184 - He was a fellow of the royal societies of London and Edinburgh, and a member of some other learned bodies.
Page 278 - The pieces of limestone are so markedly different from the calcareous bed enclosing them that they cannot be confounded with it. The rock fragments are of unequal distribution in the deposit, both laterally and vertically, sometimes composing almost half of it, and sometimes being almost entirely absent. They vary from a fraction of an inch to several inches in diameter and are indiscriminately mixed.
Page 412 - The geographic development of the eastern part of the Mississippi drainage system. Am. Geol., vol. xi, 1893, pp.
Page 633 - Agency of organisms; 2". Chemical precipitation; 3. By mechanical methods. It is the general opinion of geologists that limestone rocks are the result almost entirely of the consolidation of lime removed from the sea water through the agency of life, and that they consist of the remains of foraminifera, crinoids, corals, etc., or their fragments, embedded in a more or less crystalline matrix resulting from subsequent alteration of the original deposits. This, however, has been seriously questioned....
Page 211 - The Crocodilian Remains found in the Elgin Sandstones, with remarks on the Ichnites of Cummingstone.
Page 441 - The non-feldspathic intrusive rocks of Maryland and the course of their alteration.
Page 631 - I obtain 113 tons as the total amount of matter in solution discharged into the Atlantic basin per annum from each square mile of area drained into it. Of this 49 tons consist of carbonate of lime and 5.5 tons of sulphate and phosphate of lime.4 Mechanical sediments.
Page 417 - Price 10 cents. 65. Stratigraphy of the Bituminous Coal Field of Pennsylvania, Ohio, and West Virginia, by Israel C. White. 1891. 8". 212pp. 11 pi. Price 20 cents. 66. On a Group of Volcanic Rocks from the Tewan Mountains, New Mexico, and on the occurrence of Primary Quartz in certain Basalts, by Joseph Paxson Iddings.
Page 629 - Our knowledge of the conditions north of the 55th parallel is limited by the want of accurate geologic data. If Cambrian and Carboniferous rocks were not deposited in the Mackenzie river basin and also on the eastern side of the area now covered by Cretaceous strata, the inference is that during Cambrian and Carboniferous time there was a land area to the east and north of the northern Cordilleran sea that may have been tributary to the latter.