GEOLOGY 



CROMER FOREST BED 



Overlying the Chillesford series at Kessingland and exposed also at 

 the foot of the cliffs at Corton is the Cromer Forest Bed — the Cromerian 

 or zone of Elephas meridionalis — a series of freshwater and estuarine de- 

 posits, comprising dark peaty clay with seeds and other plant lemains, 

 greenish stony clay, and gravel some lo or 15 feet thick. The dark 

 peaty clay forms a black bed, perhaps an old lacustrine deposit, which 

 lies in hollows above the rootlet bed, and these strata at Kessingland 

 appear generally to occupy an eroded surface of the Chillesford Clay. 

 The greenish stony clay is penetrated by roots, and has been termed the 

 rootlet bed ; remains of freshwater shells are found in the XJnio bed, a 

 gravelly layer at the base of the black bed, in which occur Unto pictorum 

 and Pisidium astartoides ; while remains of elephant, hyaena, rhinoceros 

 and deer are found at different horizons in the Forest Bed Series. 



These interesting layers have attracted much attention from John 

 Gunn, J. H. Blake and others, while the organic remains from Corton 

 were specially looked after by J. J. Colman.' The bed with rootlets 

 was first described by S. R. Pattison in 1863.^ 



It is however a difficult task to clearly make out the sequence along 

 the cliffs from Kessingland to Corton, because not only does the Forest 

 Bed Series rise very little above the sea-level, but a great portion of 

 the cliffs along their base is usually obscured by talus and blown sand. 

 It requires an attentive study on many occasions during successive winter 

 and spring seasons before a clear notion of the relations of the strata can 

 be gained. 



The story however has been made out, and Mr. Clement Reid 

 remarks that the Pliocene land fauna and flora is mostly of temperate 

 species. There were forests of oak, Scotch pine, beech, birch, elm, 

 hazel, hornbeam and cornel. The lakes were full of yellow water-lily, 

 water-crowfoot and various existing species of pond weeds ; their shores 

 were occupied by thickets of alder and willow, by osmunda, or dense 

 growths of reeds and sedges.' 



PLEISTOCENE AND RECENT 



GLACIAL DRIFT 



It must be borne in mind that the divisions in geological time are 

 simply convenient groupings. The Pliocene and Pleistocene periods 

 merge imperceptibly whether we consider the physical changes or the 

 strata which furnish the records. 



The Glacial Drifts of earlier Pleistocene age were spread irregularly 

 across the entire country, and to this mantle of clays, sands and gravels 



* Blake, 'Geology of the country near Yarmouth and Lowestoft,' Geol. Survey (1890), p. 17 ; 

 Prestwich, ^art. Journ. Geol. Soc. xxvii. 463 ; E. T. Newton, ' Vertebrata of the Forest Bed Series.' 

 ^ Geologist, vi. 207. 

 ^ Natural Science, vii. 176 ; 'Pliocene Deposits of Britain,' pp. 146, etc. 



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