GEOLOGY 



IN Buckinghamshire from the valley of the Great Ouse on the north 

 to that of the Thames on the south there are outcrops of a series 

 of geological formations, which are tilted gently towards the south- 

 south-east. Through the northern belt range portions of Jurassic 

 strata which serve to connect the county with midland regions. There 

 we find traces of the Lias, with uplands of Oolitic limestone or stone- 

 brash, and a broad vale of Oxford and Kimeridge Clays, modified towards 

 the south by outlying hills of limestone capped by Cretaceous sands and 

 clays. Still further south we come to the vale of Aylesbury which is 

 largely formed of Gault clay ; and this is succeeded in the central part 

 of Buckinghamshire by the bold Chalk range of the Chiltern Hills, 

 which, forming part of the London Basin, slope gently south-eastwards, 

 and are eventually covered by Eocene deposits and by the gravels of 

 the Thames valley. 



Throughout the entire area there are various superficial deposits on 

 hill and in vale, which help to diversify the soils of this essentially agri- 

 cultural county. 



Of the industries directly connected with the geology, those of 

 lime-burning and brick-making are the principal ; but changes here, as 

 elsewhere are in progress. The smaller brickyards cannot compete with 

 the larger, while the local road-mending materials have given place to 

 more durable stone obtained from a distance ; hence in remoter regions 

 there are fewer pits or ' geological sections ' than was formerly the case, 

 and except as lime-works many small quarries have been abandoned. A 

 striking instance of the changes is noted by Mr. A. Morley Davies, who, 

 in writing of the Thame valley in 1898, says : ' Now however the stone- 

 pits seem all abandoned and mostly levelled over ; the only one I saw 

 was being used to store Leicestershire /oad-metal.' 1 



Phosphatic deposits were formerly worked, but owing to foreign 

 competition the industry is being gradually extinguished in this country. 

 Elsewhere the market and nursery gardens of the Thames valley, the 

 dairy lands of Aylesbury, and the beech woods used for chair-making at 

 High Wycombe, give rise to occupations due more or less directly to the 

 nature of the soil. 



The county is one which is by no means devoid of interest to 

 geologists, and our knowledge is especially associated with the names of 



1 Proc. G(ol. Assoc. xvi. 19. 

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