. Bulletin of the British Museum (Natural History), Geology. Mans the mid-Cenomanian non-sequence is lost in the complex successions of the 'Sables de Maine'. The Upper Cenomanian of this area has already been discussed in the section on the Cenomanian/Turonian boundary. The most interesting feature of the 'axe de Merlerault' is that its trend is almost parallel to those plotted in the south-west of England, and appears to belong to the same structural suite. The same trends appear again in north-east France where both Jefferies (1963) and Robaszynski (1971) have described the succession in th
. Bulletin of the British Museum (Natural History), Geology. Mans the mid-Cenomanian non-sequence is lost in the complex successions of the 'Sables de Maine'. The Upper Cenomanian of this area has already been discussed in the section on the Cenomanian/Turonian boundary. The most interesting feature of the 'axe de Merlerault' is that its trend is almost parallel to those plotted in the south-west of England, and appears to belong to the same structural suite. The same trends appear again in north-east France where both Jefferies (1963) and Robaszynski (1971) have described the succession in the quarry behind the station at Bettrechies, 4 km north- west of Bavay (Nord). The 'Sarrazin de Bellignes' was regarded as Middle Cenomanian by Marliere (1939: 356, fig. 36; 1965) while Robaszynski places it within the Lower Cenomanian. The overlying 'Tourtia de Mons' contains a microfauna which indicates a position within Zone 14(i-iia). The overlying chalk contains elements of a Turonian fauna, and was included within the 'couches a grosses globigerines' by Robaszynski (1971). The relationships are very similar to those at Membury where a 'tourtia' is overlain by glauconitic chalk containing a Zone 14(i-iia) fauna. At Membury the underlying greensand may be comparable with the Sarrazin, although we have no faunal data from this level. The two successions are compared in Fig. 52. It is significant that Inoceramus labiatus first appears 1 m up the succession at Bettrechies. The position of the first appearance of/, labiatus at Membury is not known as there is a gap in the exposures at this critical level. Marliere (1965) suggested that the 'Tourtia de Mons', when traced into the centre of the Anglo- Paris Basin, could be equated with the Totternhoe Stone. This correlation has proved correct, but we place the mid-Cenomanian non-sequence at the upper surface of the Totternhoe Stone and not the base, as indicated by Fig. 52 Submergence of the Dartmoor and Ardennes Massif
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