98 



8. V. WOOD, JTJN., AND F. W. HARMER ON THE 



At Withersdale the uppormost layers consist of brown obscurely 

 stratified marly brick-eartli, which is the character the deposit 

 assumes in the Norfolk cliffs near Weybourne. These are overlain 

 very unconformably by the Upper Glacial clay, which in some of 

 the excavations is in its turn overlain by Plateau gravel. This 

 marly brick-earth appears, from other and not far distant excava- 

 tions at lower levels, to pass down into alternations of laminated 

 brick-earth and loamy sand, interstratified in which there occur in 

 one of the excavations beds of rolled pebbles. On the north side of 

 the Waveney at Starston the Contorted Drift presents the character 

 which it possesses at Elsing and Lyng (see section VII.), of a gritty 

 earth enclosing small flints and minute fragments of chalk, Nume- 

 rous as are the excavations in the Contorted Drift around Harleston, 

 they do not afford the means of showing in a satisfactory way the 

 interglacial excavation of the main valley of the Waveney, but only 

 of the small tributary valley at Starston. They, however, show 

 abundantly the considerable thickness in which this drift originally 

 extended across the region now occupied by that valley, along the 

 line of section XVII. 



Fig. 17. — Section XVII., across the Waveney Valley near Harleston. 

 (Length 4| miles. Vertical scale 17| times the horizontal.) 





N.W. 



Tributary valley. 



Large pit 

 (see fig. 18). 



East End 

 of Harleston. 



Excavations 6 furl. N.W. by 

 W. of Withersdale church, 

 River the lower one in a large 



Waveney. sand-gall in No. 6. 



1. The probable position of the Chalk. 



6. The Contorted Drift, which may perhaps be underlain by the Lower 



Grlacial sands, and even by the Chillesford (Crag) beds. 



7. Middle Grlacial. 



8. Upper Glacial. 



10. Postglacial valley-gravel and recent alluvium. 



N.B. The central portion of this line of section is conjectural for want of 

 open sections such as occur at either extremity. 



It is not unlikely also that the interglacial main valley is con- 

 cealed beneath the alluvium which covers the bottom of the ex- 

 ceptionally wide elbow in the valley at this point. 



The importance of the Starston excavation consists in its having 

 afforded, when we examined it in 1871, the only indication besides 

 the bed a of the Yare valley which we have been able to discover of 

 a land surface having existed during the interval represented by the 

 unconformity and denudation that we have been describing. 



In this excavation (section XVIII.) there occurs upon the denuded 

 surface of the Contorted Drift, and between it and the overlying 



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