Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/183

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1873.] JUDD-THE SECONDARY ROCKS OF SCOTLAND. 139


been worked on a very extensive scale, and subjected to the most diligent search, has never yielded a trace of such fossils. Neither has any trace of the reptilian scales or bones been found in any undoubtedly Old Red Sandstone beds. The Cherty Rock of Stotfield, too, is admitted on all hands to differ greatly from any recognized bed of cornstone, and strikingly from that which occurs in the immediate neighbourhood at Foths in the parish of Birnie, and which is of undoubted Old-Red-Sandstone age.

But in a district which is so hopelessly sealed up from the investigations of the field-geologist by overwhelming masses of drift as is that of Elgin, the generalizations founded on the examination of a few exposures of rock, miles apart, lose all their weight, if it should appear that the country has been subjected to great dislocations.

That the strata of the Elgin district have been thus broken up by a series of fractures is, I think, quite indisputable. Indeed I believe that no one acquainted with the area will deny the existence of a number of great faults ranging E.N.E. and W.S.W., and of cross fractures subordinate to these. In proof of this disturbed condition of the strata I would briefly notice the following circumstances.

1. The strata, when examined over the whole district, are found to dip at various angles, and at some points, as the Clashack quarry, are actually seen to be bent into great anticlinal folds.

2. Even in the small exposures of the strata visible, as between Burghead and Cummingstown and on the Findhorn, as pointed out by Professor Harkness*, and near Bishop-Mill as pointed out by Mr. Symonds†, there are indications of the existence of faults.

3. The repetition of strata which are unquestionably the same and have a considerable dip, at distant points (as for example, in the Spynie and Lossiemouth ridges, which are three miles apart), indicates the existence of such disturbance.

4. I may notice that Professor Harkness has pointed out the existence of these great lines of faulting, and has indicated their probable position.

5. Dr. Gordon has noticed the existence of patches of Old Red Sandstone lying at Pluscarden and Rininver in the midst of the Lower Silurian strata‡, identified in the former locality by the remains of fish, and in both by the marked mineral characters of the beds; and it seems to be impossible to account for the position of these except by admitting that the whole district has been subjected to great dislocation.

Lastly, I have shown that strata, proved by the most unquestionable fossil evidence to be of as recent date as the Lower Oolite, are found at Stotfield faulted against the older strata. The existence of this fault was recognized by Professor Ramsay in 1859.

The conclusion, to which I think all the facts which I have ad-

  • Quart. Journ. Geol. Soc. vol. xx. (1864) p. 432, fig. 2, p. 436, fig. 3.

† Edin. New Phil. Journ. New Ser. vol. xii. (1860) p. 97.

‡ Ibid. New Ser. vol. ix. (1859) p. 43.