Transactions of the Geological Society of South Africa, 1-3. kötetThe Society, 1896 Vols. 1-6, 49-68 include its Proceedings. |
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A. R. Sawyer Atherstone auriferous banket basin Black Reef Botha's boulders Cape Colony carbon Carboniferous clay coal beds coal measures coast conglomerate beds contained DAVID DRAPER denudation deposits depth diabase diamond district dolomite Drakensberg Dwyka Conglomerate dyke Elsburg series evidence existence extending Exton fact farm fault feet formation formed fossils fragments Geological Society geologists glacial glaciers glomerate gold granite horizontal Hospital Hill Hospital Hill slates igneous rocks Johannesburg Karoo Karoo beds Kimberley Klerksdorp Krugersdorp layers limestone Lydenburg lying Magaliesberg Main Reef series matter miles mineral mines Molengraaff Molteno Natal northern numerous observations occur ocean origin outcrop overlying paper pebbles period portion position present Pretoria Prister Prof quantity quartz quartzites Rand Rietfontein River schists sedimentary shales similar SOCIETY OF SOUTH South Africa southern specimens strata surface Table Mountain Sandstone theory thickness tion Transvaal underlying Vaal Vaal River valley volcanic Witwatersrand
Népszerű szakaszok
79. oldal - Hold out your hand," said He, at the close of a lecture that fairly electrified the world of science, as with a loud hiss a snowy substance, burning like a coal but in reality intensely cold, escaped in the palm of my hand from the strong iron vessel in which, with a pressure of fifty atmospheres, he had liquefied carbonic acid gas- — the very gas resulting from the combustion of the diamond, consisting of one atom of carbon, and two of oxygen.
38. oldal - foundation of the geological history of this country upon which we to-day are endeavouring to build the superstructure. It has always been a matter of surprise to me that so few persons have read the literature on South African geologv which has already been published.
106. oldal - ... the deposition of this formation cannot be accounted " for except by reference to glacial action. It is by the " action of glaciers, coast ice, and icebergs, and by it ' alone, that fine silt and boulders of many tons weight can ' be deposited simultaneously on the same sea or lake
79. oldal - For a substance to crystallize," he says, -> its molecules must be free to move. * * * The diamond, we know, is neither soluble nor fusible. It is the element carbon crystallized, and is consumed by heat. How, then, could it survive as a crystal in the center of a volcano? The key to solve this mystery was placed in my hands over half a century ago by one of the greatest philosophers of the age. whose lectures I had the privilege of attending. * * * > Hold out your hand...
62. oldal - Thou shalt not make to thyself any graven thing, nor the likeness of any thing that is in heaven above, or in the earth beneath, or the waters under the earth : Thou shalt not adore them nor serve them.
57. oldal - ... have been transported from places, commonly in higher latitudes, by some agency which (1) could carry masses of rock hundreds of tons in weight, and which (2) was not always dependent for motion on the slopes of the surface.
51. oldal - ... no means very clear on the point. As far as the sedimentary theory is concerned my point of difficulty has been the absence of the usual markings generally found in the sedimentary ironstones ; at the same time, I agree that there has been a great deal of change in the nature of the oud klip since deposition, and at places the iron has been dissolved and re-deposited. Since the writing of my paper I have observed at certain places, where deposited in a black clayearth, that the pebbles of " oud...
74. oldal - ... which rocks, originally fused, and when in liquid fusion, poured into veins and dykes in pre-existing rocks, are subsequently altered in specific gravity and arrangement of minerals, by the action of water acting at temperatures which, though still high, would be quite inadequate to fuse the rock ; and pyro-metamorphism, by which rocks originally stratified by mechanical deposition from water, come to be subsequently acted on by heat, and so transformed into what are commonly called the metamorphic...
50. oldal - ... hour, we proceeded on our voyage, and met with no obstacle till the evening, when we arrived at the foot of a long and strong rapid, where we encamped near the mouth of a considerable river called Umatallow, which enters the Columbia here. This river takes its rise in a long range of blue mountains, which runs nearly east and west, and forms the northern boundary of the great Snake nation. Opposite to our encampment, on the west side, is situated a large mound or hill of considerable height,...
68. oldal - ... origin. It shows, however, that the lower portions of crystalline rocks very generally assume a granitic type, and it suggests that if at any part of the earth we could bore deep enough iuto the crust we should probably come to a granitic layer.