IN THE ANGLO-PARIS BASIN 



A. Weald 



The Gault describes a narrow outcrop at the foot of the Downs from Folkestone in 

 the east, around the northern, western and southern borders of the Weald to reach 

 the sea again at Eastbourne (text-fig. i). Deposits of Middle Albian age are present 

 throughout and reach their greatest known thickness in Sussex. No section has yet 

 provided a complete and relatively uncondensed sequence. Although the greatest 

 degree of representation is to be found in the Folkestone area of Kent and between 

 Steyning and Ringmer in Sussex, even at these localities condensation at certain 

 horizons is very marked. Fortunately, further west in the northern Weald some 

 condensed horizons are greatly expanded, but this is offset by truncation westwards 

 of deposits of the higher subzones of the Middle Albian due to tectonic movements and 

 associated erosion within the cristatum Subzone. 



(i) FOLKESTONE 



In response to the general north-easterly dip, the Gault appears above the Folke- 

 stone Beds at the top of East Cliff, where it overlooks the harbour, and declines to the 

 shore in East Wear Bay. Copt Point is the promontary at the NE. end of East Cliff 

 at the entrance to East Wear Bay, and it was shortly after a substantial cliff-fall in 

 1959 that the section given in text-fig. 2 was measured. By far the bulk of the 

 fossils, for which the Folkestone Gault is famous, were collected from the foreshore 

 exposures in East Wear Bay (East Weir Bay of early authors), but due to cliff and 

 shore stabilising work carried out by British Railways, these sections are now hidden 

 beneath beach-sand (see Bisson in Smart et al. 1966 ; 293-296). It is worth recording 

 that in the period between 1948 and 1956 when remedial work obscured the sections, 

 a large slice of Gault extending from the top of Bed III to the base of Bed X could be 

 seen from the area now covered by the western half of the Toe-weighting to about 100 

 yds west of it. This slice was not greatly disturbed within itself, but at the line shown 

 by Bisson (Smart et al., 1966 ; fig. 17, p. 294) the dip was in the order of 70°-8o° 

 landwards. 



The Folkestone Gault has attracted the attention of many workers because of the 

 intrinsic beauty of its fossils. The early history of research is ably summarised by 

 Price (1879, 1880) whose bed notation is still broadly used today. De Ranee (1868), 

 however, was the first to divide the Gault into Lower and Upper Divisions and to 

 subdivide them further into eleven Beds. Price (1874, 1875) accepted De Ranee's 

 Upper and Lower Gault and also recognised eleven Beds but these did not coincide 

 with those of De Ranee. De Ranee later (in Topley 1875 ; 146) accepted the bed 

 notation of Price but they do not coincide lithologically. Jukes-Browne subse- 

 quently modified Price's account, and it is his reading of the section which has been 

 accepted by subsequent workers (1900 ; 69-83). Spath (1923-43) drew heavily on 

 the well preserved ammonite fauna of this locality, and indeed, the degree of repre- 

 sentation in his Monograph is largely a reflection of the high degree of representation 

 within the section itself. Spath (1923a, b, c ; 1926b), like Jukes-Browne (1900 ; 45), 

 expressed his zonal scheme for the Middle and Upper Albian essentially in terms of 

 the lithological sequence at Folkestone. 



