Geological MagazineHenry Woodward Cambridge University Press, 1912 |
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Page 2
... felspar , nepheline , and sodalite , and a light - grey part in which ferro - magnesian minerals , are quite subordinate , while twinned crystals of orthoclase are conspicuous and with a marked tendency to orientation along the line of ...
... felspar , nepheline , and sodalite , and a light - grey part in which ferro - magnesian minerals , are quite subordinate , while twinned crystals of orthoclase are conspicuous and with a marked tendency to orientation along the line of ...
Page 3
... felspar is high and slightly exceeds that of the nepheline . The ferro- magnesian minerals are of minor importance , their chief constituent being an amphibole , so that this rock may be added to the comparatively restricted list of ...
... felspar is high and slightly exceeds that of the nepheline . The ferro- magnesian minerals are of minor importance , their chief constituent being an amphibole , so that this rock may be added to the comparatively restricted list of ...
Page 64
... felspars seem to belong chiefly to the andesine variety , but they approach labradorite in the central parts of the ... felspar often stellate in arrangement , bound together by a central cluster of granular augite ( Plate IV , AF in ...
... felspars seem to belong chiefly to the andesine variety , but they approach labradorite in the central parts of the ... felspar often stellate in arrangement , bound together by a central cluster of granular augite ( Plate IV , AF in ...
Page 65
... felspar laths . There are several such patches both in the tachylite and in the ' stony rock ' , but they are more numerous in the latter . In all cases , however , the patches in this contact variety of the Cleveland Dyke are much ...
... felspar laths . There are several such patches both in the tachylite and in the ' stony rock ' , but they are more numerous in the latter . In all cases , however , the patches in this contact variety of the Cleveland Dyke are much ...
Page 66
... felspars are of a more alkaline type than the inner zones ; and even whole crystals of albite occur . Thus , as differentiation by crystallization proceeded we had felspar material of a more alkaline type crystallizing out , and it is ...
... felspars are of a more alkaline type than the inner zones ; and even whole crystals of albite occur . Thus , as differentiation by crystallization proceeded we had felspar material of a more alkaline type crystallizing out , and it is ...
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Common terms and phrases
abundant analcite anticline apical system appear augite band basal beds Boulder-clay Brachylepas British calcareous Cambrian Chalk character cherts clay Coal Coal-field Coal-measures conglomerates contains Cretaceous crystals deposits described Devonian district dolerite drumlins dykes earthquakes east evidence fault fauna feet felspar formation fossils fragments fringe genus Geol Geological Survey geologists Glacial gneiss granite gravel Grit Hill horizon ibid igneous rocks intrusive Journ later laterite lavas Lias Lower margin marls miles mineral Museum Naissanti nepheline occur Old Red Sandstone olivine origin outer paper peristome pits plates portion present probably Professor quadratus Quarry quartz radial Radiolaria Rhætic ridges River rows sand schists Schlüter sedimentary shales side Silurian South species specimens strata structure sulci surface tachylite Tertiary teschenite theralite thick titanaugite unconformity Upper valves volcanic Waipara Weka Pass Stone Woodward zone
Popular passages
Page 266 - Chessy deposits, that is, in a quartzose rock scattered in nuggets varying from the size of a pea to that of a walnut. All the ores carry, besides iron and silica, a small percentage of manganese and alumina, together with an amount of zinc varying from two to eight per cent.
Page 193 - On Fossil Cycadean Stems from the Secondary Rocks of Britain. Trans. Linn. Soc., vol. xxvi. pp. 675-708, pi.
Page 141 - On the Sources of the Materials composing the "White Clays of the Lower Tertiaries...
Page 342 - Notes on Stone Implements from Otaru and Hakodate, with a few general remarks on the Prehistoric Remains of Japan,
Page 68 - The work on which this paper is baaed was commenced in 1908, and was assisted in 1909 by a grant from the Government Grant Committee of the Royal Society, for which grateful acknowledgment is made.
Page 570 - Livr. 81. (13) A contribution to our knowledge of Wealden Floras, with special reference to a collection of plants from Sussex. Quart. Journ. Geol. Soc. vol. LXIX. p. 85. (14) Antarctic Fossil plants. British Antarctic (Terra Nova) Expedit. 1910. Nat. Hist. Report, Geology, vol. I. No. 1. London. (142) Wealden Floras. Hastings and East Sussex Naturalist, vol. n. No. 3, p. 126. Seward, AC and N. Bancroft. (13) Jurassic Plants...
Page 280 - ... formula for camphoronic acid. — On Pettenkofer's method for determining carbonic anhydride in air, by Prof. Letts and RF Blake. By employing precautions suggested by the authors, Pettenkofer's method can be made of great accuracy and delicacy.
Page 46 - Hill; but an examination of several exposures has failed to produce any Cretaceous fossils, while the occurrence in places of vast numbers of Balani points to a Tertiary age for the beds. As this limestone stretches right across the AtlanticPacific watershed between Cartago and San Jose, it yields clear evidence of an inter-oceanic connexion in this area in Tertiary times. Of the igneous rocks, the most interesting feature is the presence of many boulders of monzonite, indicating a plutonic mass...
Page 342 - THE STONE AGE IN JAPAN ; with Notes on RECENT GEOLOGICAL CHANGES WHICH HAVE TAKEN PLACE.
Page 82 - Note on the Correlation of some Cornish Beds with the Gedinnian of Continental Europe": GEOL. MAG., NS, Dec. V, Vol. I, pp. 403-7, London, 1904. * 3. B. Hill, "On the Relation between the Older and Newer Palaeozoics of West Cornwall,