A HISTORY OF NORFOLK 



were here and there laid down before the final melting away of the ice, 

 but for the most part they appear to have been due to the torrents thus 

 caused. Hence they may truly be regarded as Flood Gravels and their 

 formation may have initiated some of the main lines of drainage which 

 they partially occupy. They contain no contemporaneous fossils, if we 

 except the broken molar of an elephant mentioned by Mr. Reid.^ 



Occasionally these gravels occur in curious isolated sinuous ridges 

 or they appear like ' barrows ' ; such features having resemblances to 

 eskers have been noticed near Blakeney and also near Ringstead St. 

 Peter. 



Loam, perhaps newer than the Chalky Boulder Clay, occurs locally ; 

 the more noteworthy deposits being at Holkham and Burnham Overy, 

 and along the margin of the alluvial tracts at Brancaster and Hunstanton. 

 Here there is a brown loam with a few stones, 8 feet thick at the Cliff 

 Gardens, Hunstanton, which has been compared with the Hessle Clay of 

 Holderness. Although some of the loams may simply be decalcified 

 Chalky Boulder Clay, it is probable that all are not of this character. 



Possibly of the same age as this Brown Boulder Clay is the marine 

 gravel known as the ' Raised Beach ' at Hunstanton. Near the gasworks 

 there is a pit showing about 30 feet of sand and coarse gravel, with streaks 

 of clay and pebbles of hard white Chalk, Red Chalk, and various erratics. 

 It rests on a bed of seemingly rearranged Boulder Clay, and it contains 

 examples of common living species of Ostrea, Mactra, Cyprina, Tellina, 

 Purpura and Cardium. 



The several divisions of the Glacial Drifts have now been described, 

 and it will be readily admitted that they form a complex group. No 

 section is known which, in one exposure, exhibits all the divisions in 

 succession ; but by carefully studying the evidence furnished by cliff- 

 sections and pits, and elsewhere by well-borings, such as those at 

 Dereham, North Walsham, etc., we may obtain a good idea of the rela- 

 tions of the beds. We shall also learn that there are many exceptions to 

 orderly sequence, the result partly of irregular accumulation, partly of 

 subsequent disturbance. We should also be prepared to admit that 

 during the Glacial Period, while land-ice exercised the most potent 

 influence, there were periods when floating ice and coast ice may also 

 have taken a share in the production of the phenomena.* 



VALLEY GRAVEL AND LOAM 



The deposits of valley gravel and loam in Norfolk do not occur 

 over very extensive areas, excepting near Narborough and along the 

 Fenland borders south of Lynn. They fringe the rivers at a higher 

 level in their valleys than the alluvium, but are not always clearly to be 

 separated from bordering tracts of Glacial gravel. 



' Geology of Cromer, p. 94. 



* A capital * Bibliography of Norfolk Glaciology, including the Cromer Cliffs, with the 

 Forest Bed Series,' by W. Jerome Harrison, was printed in the GhiciaHiti' Magazine for 

 1897. It includes brief abstracts of the papers. 



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