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| Keywords: The Quarterly journal of the Geological Society of London (13204780465).jpg ROCKS OP THE NORTHEEN HIGHLANDS <br> 391 <br> red felspar bits of -the lowest zone The <br> pressure to which the rock has been sub- <br> jected has flattened the quartz grains ; and <br> the cleavage and alteration are similar to <br> those of the Annelidian Quartzite above <br> These beds actually lie to the east of the <br> junction so that on the strike they pass <br> under the almost horizontal gneiss East <br> of this point the Hebridean rises up and <br> meets the newer gneiss It is therefore <br> evident that this mass of quartzite is a <br> syncline sharply folded back upon itself <br> and closely squeezed in the angle between <br> the older and younger gneiss <br> The curved beds of quartzite on the slope <br> present a curious phenomenon The joints <br> are almost at right angles with the bed- <br> ding and are open much wider than the <br> planes between the beds ; so that at a dis- <br> tance the quartzite appears nearly hori- <br> zontal and the seeming beds are contorted <br> This twofold disturbance the folding-back <br> of the true beds and the contortion of the <br> slabs between the joints points to excessive <br> lateral pressure acting from the east <br> I have said that the Hebridean rises <br> towards the east so as to meet the Cale- <br> donian This is more clearly seen by de- <br> scending to the level of the stream A little <br> below the reversed fold just described <br> and a few feet above the stream is a <br> band of conglomerate about 4 inches thick <br> The pebbles which are of quartz in a ma- <br> trix of small bits of quartz and felspar <br> are flattened as if by pressure This seam <br> is un distinguishable from a thin band <br> which forms the base of the quartzite on <br> Loch Emboli It dips to the N W at 20° <br> and it rests immediately upon grey Hebri- <br> dean gneiss to the surface of which it is <br> plastered The gneiss has its normal strike <br> to the N W The dip of this conglomerate <br> shows us that the surface of the gneiss <br> slopes up towards the east and it confirms <br> the previous evidence as to the reversed <br> dip of the quartzite Following up the <br> junction we soon lose the conglomerate un- <br> der bog ; but the Hebridean can be traced <br> up the slope at about the same angle gra- <br> dually rising to the east of the quartzite to <br> meet the overhanging Caledonian <br> –º5' <br> 'S <br> £ <br> 5 <br> m <br> 2f2 36928998 113681 51125 Page 391 Text 39 http //www biodiversitylibrary org/page/36928998 1883 Geological Society of London Biodiversity Heritage Library The Quarterly journal of the Geological Society of London v 39 1883 Geology Periodicals Smithsonian Libraries bhl page 36928998 dc identifier http //biodiversitylibrary org/page/36928998 smithsonian libraries Information field Flickr posted date ISOdate 2014-03-16 Check categories 2015 August 26 CC-BY-2 0 BioDivLibrary https //flickr com/photos/61021753 N02/13204780465 2015-08-26 12 55 55 cc-by-2 0 PD-old-70-1923 The Quarterly journal of the Geological Society of London 1883 Photos uploaded from Flickr by Fæ using a script | ||||
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