14 



CRETACEOUS GROUP. 



A TABLE OF THE CRETACEOUS GROUP OF ENGLAND. 



SUBDIVISIONS. 



LITIIOLOGICAL CHARACTER. 



LOCALITIES. FOREIGN EQUIVALENTS. 



Upper Chalk 



o 



pi 

 o 



o 

 o 



Eh 



w 

 Pi 

 o 



H 



Lower Chalk, and 

 Chalk-marl. 



Chloritic BIarl 



Upper Green sand 



Nearly pure carbonate of lime, with 

 minute fragments of Shells and 

 Foraminifera, forming a white or 

 yellowish-white, soft Chalk ; the 

 upper beds of v/hich are interstra- 

 tified with laj'ers of flints, or tabu- 

 lar layers of dark silex coincident 

 ■with the stratification. 



Hard Chalk, without flints, sometimes 

 passing into Chalk-marl or hard 

 Grav Chalk. 



Light-coloured marl, full of green 

 specks of silicate of iron, with 

 numerous fossils. 



Siliceous sand, or nearly calcareous 

 sand, with grceu grains ; the rock- 

 often contains nodules of chert and 

 masses of limestone. 



Isle of Wight, 

 Lewisham, Grays, 

 Northfleet, Nor- 

 wich, Brighton, 

 Dover, Flam- 

 borou2:h Head. 



Crate blanche, French. 

 Obere Kreide, Germans. 

 ■ Etage Sinonien, d'Orb. 



Dover, Folkestone, 

 Lewes (Sussex), 

 Swafiham, Nor- 

 wich. 



Chard, Chardstock, 

 St. Catherine's 

 Down, Isle of 

 Wieht. 



TJntere Kreide,Qiexm&xis, 

 . Planer, Germans. 

 Craie tnffeau, French. 

 Etaye Tiironien, d'Orb. 



crayeuse. 



Gault . 



'l 



Dark-blue tenacious clay, sometimes 

 marly, with some concretions. 



Warminster, De- / 

 vizes,ChuteFarm, 

 Petersfield, Cam- 

 bridge, Char- 

 raouth, Dorset. 



Isle of Wight, 1 

 Folkestone, Char- 

 mouth. 



Glauconie 

 French. 

 \ Tourtia, Belgians. 

 GrUnsand, Germans. 

 Etage Cenomanien, d'Orb. 



Red Chalk 



A thin bed of hard, red Chalk, deeply a 



coloured by the pero.xide of iron, Hunstanton Cliflf, 

 and having numerous small sili- \ -Noriolk ; riley 

 ceous grains and pebbles of quartz, 1 "^y' Yorkshire. 

 &c., strewed throughout the mass. 



^ Gault, Germans. 

 Etage Albieii, d'Orb. 



Speeton Clay. 

 [Upper part.] 



^ Lower Green sand . 



'A grayish-coloured clay, the upper 

 portion containing Neocomian, tiie 

 lower portion Poitlandiau species 

 of fossil shells. 



A great areuacous formation, com- 

 posed of ferruginous sands with 

 green grains, dark-coloured clays 

 and clayey sands ; and in some 

 localities,bands of limestone known 

 as Kentish Rag. 



Filey Bay, York- 

 shire. 



Isle of White, 

 Folkestone, 

 Ilythe, Maid- 

 stone. 



Terrain NSocomien sitpc- 

 rieur of Swiss and 

 French. 

 Etage Aptien, d'Orb. 



