PROCEEDINGS COTTESWOLD CLUB 



1910 



of these two formations ? My discovery of the Shineton fossils cnabl d me 

 to answer the question. 



Working downwards in the succession in the direction of tlie Wrekin, I 

 found below the Shineton Shales a green sandstone containing Cambrian 

 fossils, and below these strata lay the quartzite, which therefore could not be 

 younger than Cambrian. This quartzite rested upon Allport's volcanic 

 series, and it rested at a discordant angle. It was therefore clear that the 

 volcanic rocks must be pre-Cambrian. I gave them the name " Uriconian," 

 from the Roman city Uriconium, which lies at the base of the Wrekin. The 

 succession thus determined proved to be the key to the Cambrian and 

 pre-Cambrian succession in the central Midlands. This area was worked out 

 by Professor Lapworth and others, with whose researches I have never inter- 

 fered, scientific etiquette demanding that each geological bishop should 

 confine himself to his own diocese. 



The succession at Nuneaton is closely similar to the order made out 

 in Shropshire. A shale with Cambrian fossils is underlain by arenaceous 

 beds with a quartzite at the base. This quartzite rests unconformably upon 

 the Caldecote volcanic rocks, which are therefore of pre-Cambrian age. It 

 would scarcely be rash to call them " Uriconian," but in the absence of 

 fossils we cannot determine the point with certainty. 



Subdivision of the Cambrian Beds in the Nuneaton-Atherston Area : — 



Merevale or Dictyonema-Shales. Thin bedded 

 greenish-grey shales (best seen in an old quarry 

 200 yards West of Merevale Abbey). 



Oldbury Shales (Black Shales of Malvern and 

 Lower Dolgelly Beds of North Wales). Mudstone 

 with carbonaceous bands, but less felspathic 

 than the underlying Purley Shales. (Chapel 

 End and quarry at Oldbury reservoir). 



Purley Shales. Purple mudstones with bands of 

 pale green shales ; very felspathic. (Purley 

 Lane). 



Camp Hill Quartzite. (Comley and HoUybush 

 Sandstone) with associated Hyolithus - Lime- 

 stones and Shales, stained red with iron and 

 manganese. 



Shale-band. 



OJ 



d. 



Tuttle-Hill Quartzite (Quarry in fork of roads 

 north of Camp Hill Farm, and opposite Midland 

 Railway Station). 



Two shale-bands with a relatively thin median 

 layer of quartzite. 



Park-Hill Quartzite with derived fragments of the 

 underlying Caldecote rocks in the basal layer. 



Unconformity. 



Pre-Cambrian I Volcanic breccia, grits and quartz-felspar tuffs, 

 (? Uriconian) \ with intrusive dykes of porphyritic basalt. 



