Vol. 67.] PERMIAX TO THE TRIAS IN NOTTINGHAMSHIRE. 97 



however, a difference in the direction of throw in a fault in the 

 Carboniferous and Permian rocks is clearly proved in the Annesley 

 district and elsewhere. 



The Wadworth section has been entirely destroyed, but a new 

 one has been opened (August 1909) at a lower level, and this 

 shows the presence of an elongated dome of flaggy limestone below 

 the Marl. The limestone, of which about 10 feet was seen, could 

 be easily matched in the Lower Magnesian Limestone of the 

 Mansfield district. The presence of the anticline, in which the 

 strata have a dip of about 10°, and which is quite similar to those 

 described above as occurring near Hucknall Torkard over Coal- 

 Measure faults, is a further indication that the strata here may 

 be disturbed by the Edlington-Wood fault. 



Geological Survey Memoirs have not been issued for the district 

 between Tickhill and Pontefract, although there are notices of the 

 Permian rocks in the Memoir on' the Yorkshire Coalfield, and a 

 brief note on the Permian of Pontefract, in the Explanation of 

 Quarter-Sheet 87 N.W., 1 which do not bear on the present question. 

 Near Tadcaster, however, the Survey Memoir (W. T. Avcline & 

 others, 1870, pp. 9, 10) states that the Middle Marl consists 



' of red or variegated marls, with beds of soft sandstone sometimes, and in 



some parts of its range gypsum The thickness of the Middle Marl varies 



considerably; it is sometimes absent altogether, and it is probable that it was 

 very irregularly deposited ; the greatest thickness in this district is somewhere 



about 50 feet The Upper Limestone differs considerably from the Lower 



Limestone, being generally harder, thinly bedded, and full of fossils. It con- 

 tains little or no magnesia [The L T pper Eed Marl (e 5 )] is probably a very 



thin irregular deposit. It is precisely similar in its lithological character to 

 the Middle Marl.' 



Minor unconformities are stated to occur between different 

 members of the Permian formation here. The most important is 

 in the railway-cutting near Tadcaster, where the 



- 1 Middle Marl has there thinned away to a mere seam, so that the Upper 

 Limestone rests almost directly on the Lower, and at the base of the former 

 there is a thin bed of gravel formed of Lower Limestone pebbles.' 



In the Harrogate district Fox-Strangways 2 noted that at the 

 bottom of the system occurs a Lower Marl and Sands very like 

 the Bunter Sandstone, but with thin seams of unctuous white clay, 

 followed by quicksand. Above is the Lower Magnesian Limestone, 

 175 feet thick. The Middle Marl follows, and is composed 

 of red marls and soft red sandstone, sometimes very like that of 

 Triassic age. The Upper Marl is not known in the district, but 

 the Bunter is represented by ' a soft, brick-red, thick-bedded sand- 

 stone, containing occasionally thin marly partings.' 



North of this district no information bearing on the present 

 •question is to be obtained from the Geological Survey Memoirs. 



1 A. H. Green & E. Russell, 1879, p. 11. 



2 C. Fox-Strangways, 1908, p. 11. 



Q. J. G. S. No. 265. h 



