The American Journal of ScienceJ.D. & E.S. Dana, 1888 |
Dentro del libro
Resultados 1-5 de 34
Página 31
... bowlders , scoria and ashes of such an eruption . 4. Eruptive characteristics of a Basalt - volcano . - The ob- vious results of superior mobility and density in lavas , are , as in other liquids : ( 1 ) First greater velocity on like ...
... bowlders , scoria and ashes of such an eruption . 4. Eruptive characteristics of a Basalt - volcano . - The ob- vious results of superior mobility and density in lavas , are , as in other liquids : ( 1 ) First greater velocity on like ...
Página 127
... bowlders , reaching three or four feet in diameter , sometimes of Piedmont gneiss ( which crops out in the river channel within a few miles of Dutch Gap ) , but more frequently of quartzite sometimes containing Scolithus borings and ...
... bowlders , reaching three or four feet in diameter , sometimes of Piedmont gneiss ( which crops out in the river channel within a few miles of Dutch Gap ) , but more frequently of quartzite sometimes containing Scolithus borings and ...
Página 128
... bowlders of gneiss and vein - quartz ( quartzite being altogether absent ) up to two feet or more in diameter , together with hete- rogeneous sand containing a considerable element of finely divided diffused clay ; while lenticular beds ...
... bowlders of gneiss and vein - quartz ( quartzite being altogether absent ) up to two feet or more in diameter , together with hete- rogeneous sand containing a considerable element of finely divided diffused clay ; while lenticular beds ...
Página 129
... bowl- ders ) , and the upper consisting of irregularly and discontinu- ously bedded clays , with occasional intercalated beds of sand and pebbles . The clays comprising the greater part of the upper member , like those intercalated ...
... bowl- ders ) , and the upper consisting of irregularly and discontinu- ously bedded clays , with occasional intercalated beds of sand and pebbles . The clays comprising the greater part of the upper member , like those intercalated ...
Página 136
... bowlders , occur at various horizons in each member , there is some doubt as to the importance of this apparent un- conformity . Fossils . - Until recently animal remains were believed to be exceedingly rare in the formation : fragments ...
... bowlders , occur at various horizons in each member , there is some doubt as to the importance of this apparent un- conformity . Fossils . - Until recently animal remains were believed to be exceedingly rare in the formation : fragments ...
Contenido
35 | |
51 | |
60 | |
89 | |
114 | |
120 | |
143 | |
151 | |
427 | |
438 | |
448 | |
467 | |
475 | |
483 | |
490 | |
506 | |
160 | |
166 | |
179 | |
197 | |
204 | |
205 | |
212 | |
229 | |
243 | |
249 | |
258 | |
264 | |
282 | |
290 | |
298 | |
307 | |
328 | |
334 | |
341 | |
344 | |
350 | |
364 | |
367 | |
388 | |
394 | |
401 | |
407 | |
410 | |
418 | |
424 | |
39 | |
48 | |
56 | |
63 | |
71 | |
77 | |
79 | |
87 | |
162 | |
167 | |
175 | |
208 | |
222 | |
227 | |
236 | |
247 | |
254 | |
269 | |
275 | |
286 | |
303 | |
397 | |
410 | |
427 | |
443 | |
450 | |
458 | |
465 | |
472 | |
479 | |
Otras ediciones - Ver todas
Términos y frases comunes
acid angle appears arkose augite beds botanical bowlders Cambrian cent chlorite clay Columbia formation containing crater Cretaceous crystalline crystals deep-sea deflection deposits depth described determined diameter diorites displacement electrometer Emmons Eocene epidote error eruption evidence fact fauna feet fossils galvanometer Geol gneiss grating gravel hornblende Hudson Terrane hydrogen iron Journal Kilauea lake Laramie later lava length limestone liquid Lower Silurian magnetic mass measured medusa method miles mineral mountain nearly observations obtained occur paper pebbles Piedmont plain plane plates portion Potomac formation Potsdam Prof Professor quartz quartzite region relations river rocks sand sandstone schists shales side slope species specimens speculum metal strata stratigraphic sulphuric summit surface Survey Taconic area Taconic slate Taconic System temperature terminal moraine Terrane tion U. S. Geological unconformably Upper Taconic valley vapors velocity volts volume wave-length
Pasajes populares
Página 426 - Microseismic shock: recorded by a single seismograph or by seismographs of the same model, but not by several seismographs of different kinds; the shock felt by an experienced observer.
Página 75 - According to the terms of the trust, a bronze medal, and the balance of the interest arising from the fund, are to be awarded annually for the best publication, exploration, discovery, or research in the sciences of geology and paleontology, or in such particular branches thereof as may be designated.
Página 180 - This school, of high repute, was established at that place in 1812 as the College of Physicians and Surgeons of the Western District of New York.
Página 194 - But even my friend's rare dialectic skill and copiousness of apt illustration could not drive me from my agnostic position.
Página 27 - ... (1) a rising in level of the liquid lavas and of the bottom of the crater ; (2) a discharge of the accumulated lavas down to some level in the conduit determined by the outbreak ; (3) a down-plunge of more or less of the floor of the region undermined by the discharge.
Página 197 - I declare that you know niy book as well as I do myself, aud bring to the question new lines of illustration and argument in a manner which excites my astonishment and almost my envy." "As Hooker lately said in a note to me, you are, more than any one else, the thorough master of the subject.
Página 59 - The different groupings shade off' so imperceptibly the one into the other that it is impossible to erect a definite boundary between any two adjacent bodies and to say that the body on this side of the line is an element, while the one on the other side is non-elementary, or merely something which simulates or approximates to an element.
Página 163 - But to the westward it has dry declivities, which are comparatively even at base, with little running water. A direct connection is thus evinced between a windward exposure, and the existence of valleys ; and we observe also that the time since volcanic action ceased is approximately or relatively indicated, for it has been long enough for a valley to have advanced only part way to the summit.
Página 123 - ... were located; and across the necks of the inter-estuarine peninsulas the pioneer routes of travel were extended from settlement to settlement until the entire Atlantic slope was traversed by a grand social and commercial artery stretching from New England to the Gulf States. As the population grew and spread, the settlements, villages, and towns along...
Página 192 - ... of our strictly alpine species common to Europe — all but one of them arctic in the Old World — are not known to cross the arctic circle on this continent. This, however, might perhaps have been expected, as it seems almost certain that the interchange of alpine species between us and Europe must have taken place in the direction of Newfoundland, Labrador, and Greenland rather than through the polar regions.