GEOLOGY 



Rollwright or Rollerich Stones, are masses of one of the higher Inferior 

 Oolite limestones distinguished as the Chipping Norton Limestone. 1 



The county boundary just includes areas of the Northampton Sands 

 south and east of Long Compton, near Whichford and near Epwell ; and 

 there are several small outliers in the same neighbourhood. According 

 to Professor Judd, the beds forming these tracts consist of limestone, 

 sands and ironstones. In the outlier west of Whichford, beds of white 

 freestone are underlain by sands. 2 



The higher clayey and calcareous beds of the Great Oolite just 

 enter the county in a long faulted strip east of Whichford, and again as 

 an outlier, partly let down by faults, to the east of Compton Winyate. 

 At Traitor's Ford east of Whichford the beds consist of marly limestone 

 and oolite ; while east of Compton Winyate they are very similar. 3 The 

 lowest beds usually consist of clay with Osfrea and Gervillia, and may 

 represent the Upper Estuarine Series of the midland counties. 



PLEISTOCENE AND RECENT 



The deposits in our district which next succeed to those last 

 described are certain irregular patches of sand, gravel, and stony clay 

 which lie sporadically over the edges and fill up hollows in the surface 

 of the older rocks. They belong to a time so long subsequent to the 

 formation of the Oolitic beds that during the interval the Upper Jurassic 

 rocks and some of the Cretaceous were not only deposited to the thick- 

 ness of several thousand feet over a slowly sinking sea bottom, but were 

 subsequently by gradual upheavals of the earth crust raised above the 

 sea-level and worn down by rain and rivers to a surface configuration 

 much the same as obtains at the present time. Over the irregular land 

 surface so produced were strewn the glacial deposits or Drift, the pro- 

 ducts of glaciers and ice-sheets which at this time spread over much of 

 the northern hemisphere. By the combined influence of astronomical 

 causes and geographical changes the temperature had become reduced ; 

 the moisture falling on the earth's surface accumulated as snow ; the 

 separate tracts of permanent snow invaded the intermediate ground till 

 at the maximum much of the northern hemisphere was buried under a 

 thick pall of ice, which over Britain extended as far south as the valley 

 of the Thames. 



As has been shown by the researches of local glaciologists notably 

 Dr. Crosskey, D. Mackintosh, and Mr. W. J. Harrison the Midlands 

 were the meeting-place of three great glaciers; 4 one descended from the 

 Arenig mountains in north Wales and entered our district by way of the 

 Vale of Llangollen and the plain of Shropshire, scattering blocks of Arenig 

 rocks about the country between Birmingham and Bromsgrove. The 

 second or Irish Sea Glacier was made up of confluent ice-flows from the 



1 H. B. Woodward, op. cit. pp. 151-2. 



* H. B. Woodward, op. cit. p. 156. 3 H. B. Woodward, op. cit. pp. 333, 335. 



4 For an excellent summary on the Glacial Geology of the Birmingham District see W. J. Harrison, 

 Proc. Geol. Assoc. xv. (1898), 400. 



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