GEOLOGICAL STRUCTURE OF SUSSEX. 



23 



Formatinns. Principal Divisions. 



ALLUVIAL DEPOSITS. 



Subdivisions. 



Localities. 



§IV. 



ALLUVIAL 



FORMATIONS. 



'Calcareous rubble, beds of gravel") ti • \.^ /-^vir 

 and sand. ^ | Brighton Cliffs. 



Chalk rubble, and beds of ochra-~| r\ ^r. •» i i • .1. 



1 -ii. 1- i,»i 11 1 I On the summits, slopes, and m the 



r.Tv tZ'. ^^ ^ I rallies, of the Downs. 



!■ Brighton HillSj hills near Piddinghoe. 



xii. DILUVIUM. ■{ chalk flints. " ' j 



Boulders of ferruginous breccia 

 Druid sandstone, &c. 



'^^^;^S^:^:X^' iNear Brighton, Arundel, &c, 

 'Blue clay, silt, &c. Lewes Levels. 



xiii. ALLUVIUM, Tufaceous depositions. Spring, near Pounceford. 



(the effect of causes<( Sand and comminuted shells "j 

 still in action.) I drifted inland by winds from >Near Shoreham. 

 l^ the sea shore. } 



The general inclination of the beds is towards the south-east, conse- 

 quently, a hne drawn from the west, tlxrough the interior of the country, 

 would pass over the basseting edges of the strata in regular succession. 

 On the surface the occurrence of a new formation is for the most part in- 

 dicated by the intervention of a rivulet or valley, by a difference in the 

 physical appearance of the country, and a corresponding change in the 

 nature of the soil and its productions. 



On the annexed map, I have dehneated the outcrop, or geographical 

 extent of the strata, with as much accuracy, and detail, as my time and 

 opportunities for examination would permit, and have subjoined a section 

 of the country, from Castle Hill, near Newhaven, to Little Horsted, which, 

 with but one exception, comprehends the entire series of the Sussex 

 formations. 



The plan of the stratification, (Table 3, fig. 1.) is merely ideal, and in- 

 tended to illustrate the arrangement of the beds, and convey a general 

 idea of the geological structure of the district. 



I shall now proceed to describe the strata according to their natural 

 order of succession, beginning with the lowest or most ancient deposit. 



