GEOLOGY 



they are thus described by Mr. Aveline : ' The shales have a thickness 

 of about 15 feet; they are of a blue and light brown colour, have a 

 marly character and are interstratified with bands of hard compact lime- 

 stone, full of fossils.' Of these he records Scbizodus scblotbeimi, S. truncates 

 and Pleurophorus costatus, and plant remains in some of the harder bands. 1 

 In the memoir on the sheet to the north, 82 S.E., are described 

 two sections of about 20 feet, seen in road-cuttings over the edge of 

 the Magnesian Limestone escarpment near Skegby and on Fulwood 

 Top. Here the limestone passes down into beds of soft sandstone of a 

 brown colour, interstratified with which are more or fewer bands of 

 hard compact fossiliferous limestone. These contain the same organic 

 remains as those named above, except that Bakewellia ceratophaga takes 

 the place of Scbizodus scblotheimi. In colliery sinkings this portion of 

 the series cannot easily be recognized except by finding the breccia below 

 and the Magnesian Limestone above. Between these limits at Linby Col- 

 liery there are alternations of blue bind and various bands of limestone, 

 28^ feet in all; at Shireoaks the record of ' limestone bands and bands of 

 blue metal, 1920 feet,' represents the same beds. At South Scarle there 

 are 138 feet in the same interval, and at Southcar as much as 185 feet 

 between the lowest massive limestone and the Coal-Measures. The 

 following records of these last two borings through post-Carboniferous 

 strata are given for reference : 



SECTION OF BORING AT SOUTH SCARLE 2 SECTION OF BORING AT SOUTHCAR ON THE IDLE 3 



ft. ft. 



River Gravel 21 Alluvium 32 



Lias 29 Upper Keuper '05^ 



Rhaetic 15 Lower Keuper [533] .... ~| z oj_ 



Keuper Marls 688 [Upper Red Sandstone, 75^] . . j 



Keuper Sandstones 2o8 Hunter Pebble Beds [273^] \ i 



Bunter Pebble Beds 318^ [Lower Red Sandstone, 161] . . J 4 



Lower Red Sandstone . . . . 223 Upper Permian Marls with 9 ft. 



Upper Permian Marls . . . . 1 1 8^ seam of Anhydrite and some 



Upper Limestone 43^ Gypsum 89 



Middle Permian Marls . . . . 150 Upper Limestone 53 



Magnesian Limestone .... 68 Middle Permian Marls with Gyp- 

 Sandstone 20 sum veins [148] 132 



Marl Slate 118 Magnesian Limestone [56] . . 273 



Breccia i [Grey Limestone and Shales, 201] 



2,022 1,727^ 



Coal-Measures, see p. 7. Coal-Measures, see p. 8. 



The term Marl Slate here used is the name of a group occupying a 

 similar position in Durham. The characters of the groups are scarcely 

 identical, the latter being a fissile rock with many fish-skeletons in the 

 intervals of the laminae, and not containing the shells found in the 

 former near Nottingham. It will be seen that the group has greatly 

 thickened towards the east. 



1 Geol, Survey Mem. sheet 71, N.E. 



1 Dalton, Geol. Survey Mem. sheet 83. This account differs from those given by all earlier writers. 

 3 Dunstan, Midi. Inst. Mm. Civ. and Mecb. Eng. Trans, vol. xiv. Extra details in square brackets. 



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