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PROC. COTTESWOLD CLUB vol. xiii. (3) 



The Salisbury Meeting 



The Vale of Pevvsey is an interesting example of a 

 particular phenomenon of geomorphy. It illustrates what 

 has been called a " valley of elevation," the result of the 

 denudation of an anticlinal fold. The vale has been 

 formed along the axis of the anticline, while the materials 

 were carried away by the rivers which drained north and 

 south from the anticline. Of these rivers the Salisbury 

 Avon is the only one now in existence. It started on 

 the high ground of the anticlinal axis when the Vale of 

 Pewsey was still filled with strata as high as the hills 

 which bound it ; and, cutting for itself the channel which 

 now forms a gorge south of Upavon, it carried away the 

 softer rocks which separated the north and south Chalk 

 hills around Pewsey. In doing this it developed a series 

 of lateral streams more or less along the axis of the 

 anticline, and these streams now form its head waters. 



Fig. 15. Diagram of Kennet Syncline and Pewsey Anticline. The dotted 

 lines show the former position of the Eocene. The horizontal 

 lines the gorge cut by the Avon. 



The annexed diagram. Fig. 15, shows the structure of 

 the anticline, roughly indicating the general formation 

 of the county from north of Swindon to south of Pewsey, 



