326 



M. F. L. COENET ON THE UPPER CEETACEOtTS SERIES 



have excavated the existing valley in which the river Haine like- 

 wise flows from east to west. 



The subjoined diagram (fig. 1) gives a general idea of the super- 

 position of these beds. It is taken from north to south and passes 

 by the town of Mons, situated on an isolated hill in the middle of 

 the valley of the Haine. 



Fig. 1. — Section througJi the Haine Valley. 

 (Yertical scale 1 : 20,000 ; horizontal scale 1 : 160,000.) 



Mons. 



Eribus 

 Hill. 



Ciply. Fault. 



Tertiary 

 Strata. 



(\. Upper Ypresian System. Sands with Nummulites planulatus, 

 I 2. Lower Ypresian System. Clay (London Clay). 

 •{ 3. Landenian System. Sands and Clays (Thanet Sands). 

 I 4. Montian System. Freshwater Limestone and coarse marine 

 \^ Limestone. 



Cretaceous J 5. Upper Cretaceous beds with phosphate of lime. 

 Strata. 1 6. White Chalk, Grreen Marls and Sands, &c. 



Palaeozoic 



Strata. 



Carboniferous 

 Series. 



Devonian ] 

 Series. / 



'7. Schists, Psammites, and Sandstones with coal 



(Coal-measures). 

 1 8. Carboniferous Limestone (Mountain Lime- 

 y stone). 



Sandstones, Quartzites, Schists (Lower Devonian 1. 



The denudation which has excavated the valley in which the 

 Tertiary strata are deposited has cut deeply into the Cretaceous 

 beds, but has left intact on the southern slope the zone marked 

 No. 5 in our diagTam. This zone contains the phosphatic beds, 

 which I now proceeed to describe. 



In their various geological publications, M. Briart and the author 

 of this paper have established in the Cretaceous series of the 

 province of Hainaut six great divisions or stages which they have 

 subdivided into groups. The two upper stages are constituted as 

 follows : — 



6th Stage. 



5th Stage. 



r Tufaceous Chalk of Ciply (Tufeau de Ciply). 

 \Malogne Conglomerate (Poudingue de la Malogne). 

 ( Brown Phosphatic Chalk of Ciply. 

 I Coarse Chalk of Spiennes. 

 ■ White Chalk of Nouvelles. 



White Chalk of Obourg. 

 j White Chalk of Trivieres. 

 l^ White Chalk of St. Vaast. 



I shall only discuss here the beds above the White Chalk of 

 Obourg. 



