A HISTORY OF NOTTINGHAMSHIRE 



the commencement of a larger group which occurs in south Yorkshire, 

 and forms the highest member of the Permian anywhere seen. The 

 Upper Marls have been called, in reference to their supposed equivalents 

 in Germany, the Banter Schiefer. There can be no question however 

 that all these red marls belong to one, i.e. Permian, group, for the base of 

 the Trias transgresses from one to the other. 



These Marls are thicker in the eastern borings, for whereas at their 

 outcrop (in south Yorkshire) there are only 50 feet of them, at Southcar 

 and South Scarle respectively there are 89 feet and ii8| feet. In the 

 former place they contain a remarkable 9 feet bed of anhydrite, and also 

 some gypsum, which is found also in the Lower Marls there and in the 

 Upper Marls at Oldcoates. 



THE TRIASSIC SYSTEM 



Although this system retains the name of Trias applied to it in 

 Germany as consisting of three parts, there are in England two only, 

 which after their German equivalents are called the Bunter and the Keufer, 

 the central member, or Muschelkalk, being the absent member. These 

 two formations together occupy the greater part of the whole county 

 the strata already dealt with forming merely the western fringe, as the 

 Jurassic form the eastern and southern fringe of it. 



The Trias on a large scale lies unconformably on the Permian. At 

 any single point it may seem to be conformable, but it passes indifferently 

 over all the members in turn from the Upper Marls to the Magnesian 

 Limestone, and passes beyond the limits of all to lie directly upon the 

 Coal-Measures. And this is not due to a simple overlap by a later 

 stratum. The Trias could not have been deposited where it is now found 

 unless the lower strata has been irregularly denuded, so as to leave outliers 

 in one spot and not in another with the Trias lying equally over all. 



THE BUNTER SERIES consists almost entirely of sandstones, which in 

 parts are plentifully supplied with pebbles, as is so commonly the case 

 with the basal beds of a new series though here through a greater thick- 

 ness than usual. The principal deposit of pebbles occurs in the middle 

 portion, from which circumstance this part is called the Pebble Beds, 

 while the portion below is called the Lower Red and Mottled Sandstone 

 and that above, when it occurs, the Upper Red and Mottled Sandstone. 



For the greater part of its range the Bunter sandstones rest upon 

 various members of the Permian strata, and are raised up with them to a 

 considerable height. Its base at Bobbers Mill is 107 feet above O.D. 

 At Hempshill the base has risen to 270 feet, while at Bulwell Spring to 

 the east it has descended to 175 feet, and at the colliery to 126 feet, these 

 last three showing the easterly dip. At the upper end of the Leen 

 valley the base appears to be at about 430 feet. At Mansfield it attains 

 its maximum elevation in a hill of 588 feet, which includes drift gravels, 

 so that its base is probably less than 500 feet above O.D. From this 

 point it descends at Warsop to 210 feet, at Cuckney to 180 feet, here 



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