Yol. 6^.~\ INFERIOR OOLITE OF THE RISSINGTON-EURFORD DISTRICT. 437 



27. Ihe Inferior Oolite and Contiguous Deposits of the 

 District between the Rissingtons and Burford. By Linsdall 

 Richardson, F.G.S. (Read June 19th, 1907.) 



Contents. 



Page 



I. Introduction 437 



II. Comparison of the Inferior-Oolite Deposits of the Bath- 

 Do ul ting and Eissington-Burford Districts 438 



III. Description of Sections 440 



IV. Conclusion 442 



I. Introduction. 



The upland district between the Rissingtons on the west and 

 Burford on the south-east is much furrowed by combes, but, owing 

 to the highest beds that have escaped denudation having been 

 inclined south-eastward, the surface has a general slope in that 

 direction. 



On the north-east lies the southern portion of the Moreton Valley, 

 on the west the flat-bottomed Vale of Bourton. The one valley 

 is strewn mainly with sand and pebbles brought from a distance, 

 the other with material of purely-local origin. Both valleys have 

 had a somewhat similar origin : the Moreton Valley has resulted 

 from the denudation of an anticline, along which the Inferior- 

 Oolite rocks must always have been thin, the Yale of Bourton 

 from the denudation of an ellipsoidal pericline. 



The western and north-western limits of the district converge 

 to the north, conjoining at the promontory-like Iccomb Hill, which 

 overlooks the narrow valley traversed by the railway between Stow- 

 on- the- Wold and Chipping- Norton Junction. On the south is the 

 Barrington-Taynton Valley, and on the south-east the neck of high 

 ground that joins the tract under consideration to the main 

 hill-mass. 



The * solid ' rock that floors the Vale of Bourton, the valley to 

 the north of Iccomb Hill, and the Moreton Valley, is Lower Lias. 

 A gentle slope leads up to the Marlstone platform, upon which 

 Little Rissington is wholly, and Great Rissington is partly built. 

 The Marlstone platform extends from Dodd's Mill northwards along 

 the eastern side of the Bourton V alley, round Iccomb Hill, past 

 Iccomb village, and Westcott, Idbury, and Fyfield to Little Milton ; 

 but on this north-eastern side of the hill-country, as the Marlstone 

 is traced from north-west to south-east, it becomes more and more 

 difficult to locate. The Marlstone also appears in places in the 

 centre of the district — in the deep valleys around Tangley and 

 Taynton. 



