Radioactivity and Geology: An Account of the Influence of Radioactive Energy on Terrestrial HistoryA. Constable & Company, Limited, 1909 - 287 Seiten |
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Radioactivity and Geology: An Account of the Influence of Radioactive Energy ... John Joly Keine Leseprobe verfügbar - 2019 |
Häufige Begriffe und Wortgruppen
accumulation actinium active deposit alpha ray Alps amount of radium appears assume atmosphere atoms average basalt beneath Boltwood calcareous calculation calories cent chlorine conductivity connexion considerable contained coral crust cubic centimetre denudation depth derived detrital earth effects electroscope emanation of radium equilibrium amount escape estimate evidence exist experiments fact Finsteraarhorn flask folds geological age geotherms Globigerina Ooze gneiss Gothard gradient gram of radium grams per gram granite halo helium igneous rocks interior involved ionization J. J. Thomson kilometres layer mass massif measurements ments method metres miles millimetre millions minerals mountain observed ocean ooze origin particles Phil phosphate precipitation probably Proc produced quantity of radium radiation radio radioactive radioactive elements radioactive energy radioactive materials radioactive substances Radiolarian Ooze radiothermal rays rivers Rutherford sedimentary rocks sediments Simplon Simplon tunnel sodium solution Strutt suppose surface temperature thermal thickness thorium tion tonnes transformation tunnel uranium
Beliebte Passagen
Seite 98 - ... Appalachian Range reached from New York to Alabama and had a breadth of 100 to 200 miles, and the pile of horizontal beds along the middle was 40,000 feet in depth. The pile for the Wahsatch Mountains was 60,000 feet thick, according to King. The beds for the Appalachians were not laid down In a deep ocean, but In shallow waters, where a gradual subsidence was in progress ; and they at last, when ready for the genesis, lay In a trough 40,000 feet deep, filling the trough to the brim. It thus...
Seite 97 - Appalachians belong, is made out of the sedimentary formations of a long preceding era ; beds that were laid down conformably, and in succession until they had reached the needed thickness; beds spreading over a region tens of thousands of square miles in area. The region over which sedimentary formations were in progress in order to make, finally, the Appalachian range, reached from New York to Alabama, and had a breadth of 100 to 200 miles, and the pile of horizontal beds along the middle was 40,000...
Seite 90 - For the rest these 2,000 meters of granite belong to the massif of the Finsteraarhorn, and, geologically speaking, they do not share in the composition of the St. Gothard. Perhaps these two massifs belong to different geological periods (as supposed for geological reasons long ago). What wonder, then, if one of them be cooler than the other.
Seite 172 - Peaceful cooling may await the earth, or catastrophic heating may lead in a new era of life. Our geological age may have been preceded by other ages, every trace of which has perished in the regeneration which has heralded our own. " Whatever be the future or the past of our world, we have the untrammelled regions of space in which such varied destinies must surely find their accomplishment. The planets may now be in varying phases of such great events. And when a star appears in the heavens, where...
Seite 81 - Its value is incalculable, not only from the scientific but from the practical point of view. The...
Seite 111 - The energy, as we have already remarked, is in fact transported with the sediments— the energy which determines the place of yielding and upheaval, and ordains that the mountain ranges shall stand around the continental borders. Sedimentation from this point of view is a convection of energy.
Seite 251 - With an interest almost amounting to anxiety, geologists will watch the development of researches which may result in timing the strata and the phases of evolutionary advance ; and may even — going still further back — give us reason to see in the discrepancy between...
Seite 97 - ... thickness ; beds spreading over a region tens of thousands of square miles in area. The region over which sedimentary formations were in progress in order to make, finally, the Appalachian range, reached from New York to Alabama, and had a breadth of 100 to 200 miles, and the pile of horizontal beds along the middle was 40,000 feet in depth. The pile for the Wahsatch Mountains was 60,000 feet thick, according to King. The beds for the Appalachians were not laid down in a deep ocean, but in shallow...
Seite 18 - Taking as the simplest and most probable assumption that one atom of radium in breaking up emits one a-particle, it follows that in 1 gramme of radium 3'4 x 1010 atoms break up per second. Counting of Scintillations. It is of importance to compare the number of scintillations produced on a zinc sulphide screen with the number of a-particles counted by the electric method, in order to see whether each...
Seite 3 - Rutherford,1 with some modifications to bring it up to recent discoveries, shows the genetic relations of the radioactive elements one to another, as well as the periods of transformation in each case. It will be seen that radium itself is a comparatively short-lived substance ; its period of transformation — that is, the period required for one-half of any given quantity of the element to transform into the next element in the line of descent — is but 1760 years.