GEOLOGY 



TABLE OF STRATA FOUND IN SUSSEX 



Period 



Character of the Strata 



Approximate 



thickness 



in feet 



Recent 



Peat . . . . 

 Alluvium 

 Blown Sand 

 Shingle Beaches 



Very local . 

 Usually muddy. 

 Clean sand . . 

 Flint pebbles 



I to 5 

 up to 60 

 up to 20 

 up to 20 



Pleistocene 



and 

 Palaeolithic 



Brickearth . 



Coombe Rock and Valley 



Gravel 

 Raised Beach . 

 Glacial Deposit. 

 Plateau Gravel . 

 Clay with Flints 



Sandy loam 



Ans^ular detritus, mainly flint and 



c"halk 



Shingle, sand and clay .... 



Large erratics 



Angular gravel 



Angular flints and clay, on chalk . 



thin 

 thin 



Bracklesham Beds 

 Bagshot Sands . 

 London Clay . 

 Woolwich and Reading 

 Beds 



Shelly sand, clay and thin rock . . 500 or 600 



Greenish sands thin 



Clay, thin sands and Bognor Rock 300 

 Red-mottled clay, coarse sands, 



pebble beds, lignite and blue clay 80 to 130 



Upper 

 Cretaceous 



Upper Chalk and Chalk 

 Rock 



Middle Chalk and Mel- 

 bourn Rock 



Lower Chalk . 



Upper Greensand 



Gault . . . 



Lower 

 Cretaceous 



Folkestone Beds 

 Sandgate Beds . 

 Hythe Beds . . 



Atherfield Clay 

 Weald Clay . 



Upper Tunbridge Wells 

 Sand 



Soft chalk, with flints 



Harder chalk, with few or no flints 



Grey chalk, marly below. 

 Greenish sand, sandstone and malm 



rock 



Blue marl, coarse sand at the base . 



^oarse sane 



Grinstead Clay . . . . 

 Lower Tunbridge Wells 



Sand 

 Wadhurst Clay 

 Ashdown Sand 

 Fairlight Clay 



Fine sand and clay 



Sand, sandstone and chert, calcare- 

 ous above 



Shelly clay 



Blue and red-mottled clays, with 

 thin sands, Sussex marble and 

 Horsham stone 



^Sand and sandstone, with layers of 

 Tilgate stone at the top . 



Cuckfield Clay 



,Sand and sandstone 



Clay and sandstone 



Sand and sandstone 



Shaly clay . . 



Fine sand 



Clay and thin sands 



500 to 700 



200 



160 to 200 



40 to 80 

 300 



o to 140 

 30 to 100 



25 to 200 

 thin 



600 



115 

 15 



70 

 100 



100 



130 

 150 



360 



Purbeck Beds . 

 Portland Beds . 

 Kimeridge Clay 

 Corallian Oolite 

 Oxford Clay . 



Shales and limestones with gypsum . 

 Soft sandstones and shales 

 Black shale with ammonites, etc 

 Sands and thin oolitic limestones 

 Dark shale and thin limestone . 



400 

 105 

 1,290 

 222 

 over 1 20 



