468 Notices of Memoirs — Papers read at Brifis/i Association, 



Bkitish Association for the Advancement of Science, Yokk, 

 1906. — Abstracts of Papers read before Section C 

 (Geology). 



I. — The Glacial Deposits of the East of England. By 



F. W. Hakmek, F.G.S. 

 rilHE eastern part of Norfolk forms a low-lying area which, could 

 JL the glacial beds be removed, would seldom rise above the 

 100 foot contour. This region, therefore, with the Fenland, was 

 the first part of East Anglia to be overrun by the North Sea ice. 

 None of the resulting moraine (similar, for example, to the Contorted 

 Di-ift of Cromer) is now found in the Fenland, as it has been 

 destroyed by the subsequent advance of the inland ice-stream to 

 which the Chalky Boulder-clay was due ; its former presence is 

 evidenced by the occasional occurrence there of igneous erratics like 

 those found on the Norfolk coast. 



At this period, moreover, the North Sea ice must also have 

 advanced over Holderness and the East Lincolnshire plain. 

 A portion of the glacial deposits of those regions may therefore be 

 of equivalent age to the Contorted Drift of Cromer. As, however, 

 the movement of the Scandinavian glacier from north to south must 

 have been gradual, the Contorted Drift maybe somewhat newer than 

 the earliest of the glacial beds of North Britain. 



Before the deposition of the Chalky Boulder-clay in East Anglia, 

 the North Sea ice had withdrawn from a great part of that regii)n, 

 and it did not reappeai*. During its retreat, however, it heaped up 

 a well-marked terminal moraine in the form of a hummocky ridge of 

 drift, in places reaching 300 feet above O.D., extending 20 miles in 

 a S.S.W. direction from Mundesley and Cromer. 



The Chalky Boulder-clay of Suffolk is blue and intensely 

 Kimeridgian ; that of Norfolk is whitish, with a chalky matrix, the 

 boundai'y between the two being clearly defined. Jurassic Boulder- 

 clay, moreover, may be traced across the Fenland from Suffolk into 

 the Lincolnshiie plain, while the chalky drift of Norfolk is 

 represented by the chalky clay which is piled against the western 

 slopes of the southern part of the Lincolnshire Wolds to a height of 

 300 and 400 feet. The behaviour of the last-named drift is 

 instructive. Due to ice crossing the chalk range through a depression 

 running from north to south in the direction of the present valley of 

 the Bain, it turns suddenly to the south-east as it approaches the 

 lower ground, instead of overflowing the latter, as it must have done 

 had that course been open to it. The separation between the Jurassic 

 and the Chalky Drift is as clearly marked in Lincolnshire as it is in 

 East Anglia. Produced from the former district to the latter, the 

 line dividing them runs diagonally across the month of the Wash. 

 The author has, moreover, traced a trail of Neocomian erratics for 

 100 miles in the same direction from the plain of the Witham to the 

 neighbourhood of Ipswich. 



