IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 23 



which represent the first marine transgression over the truncated surface of the 

 Upper Cretaceous Chalk, were repeatedly assigned to the Campanian, Maestrichtian 

 or Danian. As a result, these beds were generally excluded from the Paleocene, 

 although they have been recently proved to be of definite basal Tertiary age and 

 correlated with the " Tuffeau de Ciply " of Belgium (Damotte & Feugueur 1963). 

 Similarly the lagoonal, clayey and lignitic deposits which lie between the " Cernay 

 conglomerate " or its equivalents and the base of the Cuisian, were included by some 

 authors within the Paleocene, while others placed them at the base of the Eocene. 

 Therefore, the Paleocene in the Paris Basin was very poorly defined and was generally 

 taken to include various rock units between the Upper Cretaceous and the basal 

 Eocene such as the " Tuffeau de la Fere " and the " Argile de Vaux-sous-Laon " ; 

 the " Sables de Bracheux et de Chalons-sur-Vesle " ; the " Travertin de Sezanne " ; 

 the " Calcaire de Rilly " and the " Conglomerat de Cernay ", and by some authors 

 the " Argile plastique " and the " Lignites du Soissonnais " as well, but its lowermost 

 and uppermost limits remained uncertain. Moreover, the fact that the Paleocene, 

 as defined above, in its type region, is represented by non-marine and very near- 

 shore deposits which were mainly zoned on the basis of their floral and mammalian 

 contents, made any correlation with the corresponding marine deposits practically 

 impossible. The shallow water marine fauna of the " Sables de Bracheux " and its 

 equivalents, which were described by Farchad (1936) and Rouvillois (i960) proved 

 to be largely of a localized nature and hence, of little value in correlation. 



As a result, various authors, e.g. Mangin (1957), suggested that the term Paleocene 

 should be dropped altogether and the Eocene be extended downwards (as it was 

 originally defined) to include at its base the youngest Lower Tertiary formations. 

 However, the fact that the Paleocene, in its type region and in other parts of the 

 world is generally represented by a particular sedimentary cycle and/or biological 

 unit, distinguished from that of the overlying Eocene, favours its separate treatment. 



On the other hand, long before the introduction of the term Paleocene, several 

 stages had been established to describe various segments of the succession represent- 

 ing the time span between the uppermost Cretaceous and the basal Eocene, e.g. the 

 Landenian (1839), the Heersian (1851), the Montian (1868) and the Thanetian (1873). 

 In addition various stages were introduced later, e.g. the Sparnacian (1877), the 

 Seelandian (1924) and the Ilerdian (i960). Moreover, the Danian which was 

 wrongly introduced (1846) as the youngest stage of the Cretaceous system, was 

 proved, as stated above, to represent the oldest stage of the Tertiary, and is thus 

 included as the lowest stage of the Paleocene series. However, as these type sections 

 are widely spaced, were designated by different authors, and are represented by 

 different facies (continental, lagoonal, shallow- water and deep-water marine deposits), 

 it became difficult to establish the true stratigraphical relationship between one 

 stage and the other, and between each stage and the corresponding part in the type 

 area of the Paleocene. Nevertheless, to avoid the difficulty of correlation with the 

 peculiar facies of the type Paleocene in the Paris Basin, different authors tended to 

 use various sets of the above-mentioned stage names to represent the basal Tertiary, 



