1867.] 



BUKTON RH^TIC BEDS NEAR GAINSBOROUGH. 



315 



4. On the Rh^tic Beds near GAiNSBORorGH. 

 By F. M. Burton, Esq., F.G.S. 



At the Meeting of the British Association at Nottingham in 1866, 

 I announced the discorery of the Rhaetic beds at Lea (a village 

 about two miles to the south of Gainsborough), which the lowering 

 of the gradients of the Great T^orthem line from Gainsborough to 

 Lincoln had laid bare. At the time this announcement was made, 

 the cutting at Lea was only partially worked out. Now, however, 

 that the line is in a more complete state, I am enabled to give more 

 accurate sectional and stratigraphical details than I could then. 



The following is a section of the various beds in the order in 

 which thej occur. 



Section of the Bhcetic Beds at Lea, near Gainsborough, 



No. of 

 bed. 



Lithology. 



Organic Remains. 



Thickness. 





Drift 



Fragments of White Lias, 



&c. 

 AvicuJa contorta, Schizadiis 



ft. in. 



20 



Black fissHe shale 



2 







chacinus. 





19 



Dark-grey stone with veins 



Fecten Valoniensis, A. con- 



3 





of black fibrous gypsum. 



torta, S. chacinus, Mo- 

 diola minima. 





18 



Black fissile shale, higblv 



A. contorta^ S. chacinus, 



3 





fossiliferous, with nests 



&c. 







of pyrites, veins of black 









fibroiis gypsum, and sep- 









taria. 







17 



Dark rubbly sandstone 





2 



16 



Black fissile shale 



A. contorta, S. chacinus. 



1 6 



15 



Dark highly pyritous sand- 

 stone. 





0^ 







14 

 13 

 12 



Black fissile shale 





1 



2 



1 6 



Dark sandstone 





Black fissile shale 



A. contorta, S. chacinm, &c. 



11 

 10 



Dark sandstone 





2 

 4 



Black fissile pyritous shale 



A. contorta, S. chacinus. 



9 



Hard grey laminated mi- 



Casts of A. contorta. Put- 



1 5 





caceous sandstone with 



lastra arenicola, Ferna 







pyrites. 



?, M. minima, with 



teeth, bones, coprohtes, 

 ripple-marks, and drift- 

 wood. 





8 



Black fissile pyritous shale 

 highly fossiliferous, with 

 septarian nodules. 



A. contorta, S. chacinus,&G. 



2 4 



7 



Hard fine-grained mica- 



A. contorta, teeth, scales, 



6 





ceous and highly pyri- 



and coprolites. 







tous sandstone, the mica 









in some places in large 









loose scales. 



Carried forward .... 





14 ^ 



VOL. XXIII. PART I. 



