MAKE A MEME
View Large Image
| View Original: | The_Quarterly_journal_of_the_Geological_Society_of_London_(13937403802).jpg (1760x3200) | |||
| Download: | Original | Medium | Small | Thumb |
| Courtesy of: | commons.wikimedia.org | More Like This | ||
| Keywords: The Quarterly journal of the Geological Society of London (13937403802).jpg 542 MAJOK-GENERAL C A M'MAHON ON THE HOBXBLENDE-SCHISTS <br> The facts seem to lead naturally to this conclusion and I do not <br> see how it can be avoided <br> This being so the further inferences seem natural that the eruptions <br> of diorite and granite in the cliff at Kennack Cove belong to the <br> same period as the intrusions of diorite and granite into the rocks <br> on the Kennack foreshore and that the injection of the dioritic rocks <br> at Kennack Cove in the form of quasi- banding took place during <br> the same period <br> If the rocks of the granulitic group at Kennack Cove and Cavouga <br> were injected with granite subsequent to the intrusion of the por- <br> phyritic diorite the same conclusion holds good for those on the <br> sea-shore at Holestrow Pentreath and under Yellow Cam but <br> the question remains whether the bedded granulite at Pen <br> Yoose and in that neighbourhood ought not to be separated from <br> them and whether both series viz the Pen-Yoose granulites <br> and the Kennack and Holestrow rocks of granulitic aspect were <br> injected with granite during the same or at different periods On <br> these points I think it prudent to suspend judgment for the present <br> There are several matters connected with these questions that require <br> elucidation Faults are so abundant along the coast of the Lizard <br> that the apparent relation of the granulitic rocks to the horn- <br> blende-schists differs materially in different places <br> One more exposure requires to be briefly noted At the north <br> end of Kildown Cove three strips of the granulitic group are to <br> be seen in serpentine cutting across the root of the Eny's Head <br> under circumstances that give colour to Air SomervaiFs theory that <br> the granulitic rocks have intruded into the serpentine Prof <br> Bonney's explanation of this section is that the serpentine is intrusive <br> in the granulitic group My own view is that the position of <br> the granulitic rocks here is due to faulting The more westerly <br> of the three strips has the appearance of being faulted against the <br> serpentine ; for a broad dyke of gabbro that strikes at the granulite <br> at a high angle ends sharply at the granulite and does not reappear <br> in the serpentine on the other side which it would surely do if <br> the granulite had been erupted through the serpentine and its <br> contained gabbro The natural inference is that the gabbro is cut <br> off by a fault <br> Discussion <br> The President noticed the revival of Bischofs views The <br> supposed ash-beds the late David Forbes was perhaps right in <br> considering had been produced by lava issuing into water <br> Dr G-eikie would be reluctant to accept the Author's conclusions <br> Though he had not examined the ground he could not believe that <br> the rocks there had escaped from the deformation which was so <br> manifest throughout Cornwall <br> Mr Teall commented on the complexity of the subject The <br> district had been examined by Dr Bonney and subsequently by <br> himself and although on some points the Author reconciled the 36940371 113696 51125 Page 540 Text 45 http //www biodiversitylibrary org/page/36940371 1889 Geological Society of London Biodiversity Heritage Library The Quarterly journal of the Geological Society of London v 45 1889 Geology Periodicals Smithsonian Libraries bhl page 36940371 dc identifier http //biodiversitylibrary org/page/36940371 smithsonian libraries Information field Flickr posted date ISOdate 2014-04-21 Check categories 2015 August 26 CC-BY-2 0 BioDivLibrary https //flickr com/photos/61021753 N02/13937403802 2015-08-26 05 53 32 cc-by-2 0 PD-old-70-1923 The Quarterly journal of the Geological Society of London 1889 Photos uploaded from Flickr by Fæ using a script | ||||
.jpg){kind=link}
