472 MR. D. BELL ON THE SHELLY CLAYS [Aug. 1895, 



31. The Shelly Clays and Gravels of Aberdeenshire, considered 

 in Relation to the Question of Submergence. By Dugald 

 Bell, Esq., F.G.S. (Read May 8th, 1895.) 



The high-level shelly gravels and clays of Aberdeenshire were de- 

 scribed in some detail by Mr. T. E. Jamieson, of Ellon, in two 

 valuable papers read to this Society in March 1882. 1 They have 

 also been treated of at some length by the Geological Survey of 

 Scotland, in their published memoir relating to the district. 2 As- 

 these deposits have been frequently, and quite recently, referred to 

 as proving a submergence in Scotland during Glacial times, to the 

 extent of 500 feet or upwards, 3 I would ask leave briefly to review 

 the facts, for the purpose of showing that they do not lead to or 

 warrant such a conclusion. 



1. There are, first, certain beds or undulating ridges of sand and 

 gravel which, according to Mr. Jamieson, contain fragments of 

 shells of Crag species. These extend along the sea-shore and for 

 some distance inland, a few miles north of the river Ythan, and 

 are found up to a height of 225 feet above the sea, but chiefly 

 between 100 and 200 feet. They rest on the grey Boulder Clay of 

 the district, which is formed of the debris of the gneiss, granite, 

 and mica-schist rocks prevailing there ; but they are different from 

 it, containing many pieces of yellow limestone and calcareous shale 

 belonging to some Secondary formation not found in situ in Aber- 

 deenshire. ' The shelly material occurs generally in the form of 

 fine pounded debris and small worn crumbs, with here and there a 

 larger bit, generally a hinge.' The evidences, as a whole, indicate 

 transport from the southward, and the inference is that, after the 

 deposition of the grey Boulder Clay, there had been a change in the 

 movement of the ice, bringing it more from the southward, and 

 that some patch of Crag along the coast, or near the estuary of the 

 Ythan, had been scoured out, and the debris carried northward and 

 partly inland by the ice in its progress. In short, Mr. Jamieson 

 considered that ' the gravel represents the scourings of the surface 

 which the ice carried along with it and shed off along its border.' 4 

 In this view it is a purely glacial deposit, and cannot be cited as 

 evidence in favour of even a moderate submergence. 



2. Overlying this shelly gravel is a well-marked bed of red clay 

 which extends over a somewhat wider area, covering much of the 

 low ground between Aberdeen and Peterhead. It ranges from the 

 sea-level up to about 300 feet, ' although there are here and there 

 some indications of it at a higher level.' These indications consist 

 of numerous water-worn pebbles of quartz and flint, similar to 



1 Quart. Journ. Geol. Soe. vol. xxxviii. pp. 145, 160. 



2 Mem. Geol Surv. Scotl. 18S6, Expl. Sheet 87. 



3 J. Geikie, ' Great Ice Age,' 3rd ed. pp. 139, 166. 



4 Quart. Journ. Geol. Soc. vol. xxxviii. (1882) p. 152 sb ssqj. 



