92 



MR. E. L. SHEELOCK ON THE BETATIONSHJP OF THE [Feb. 191 I. 



The floor is a hard sandstone about 3 feet thick, which has been 

 broken into 150 yards away to the south-east, and is seen to rest upon 

 a somewhat uneven surface of the dolomitic sandstone (Magnesian 

 Limestone). The junction is less marked than usual, owing to 

 both formations being sandy. 



To sum up, the sections in the Mansfield district show 

 a lateral passage of 'Permian Marl' into Bunter, as 

 distinctly as the Great Central Railway cuttings, 

 previously described, showed an upward passage. 



An unusual feature of the Bunter in the Mansfield district, which 



Fig. 6.— The sandpit of the Mansfield Sand Company, Ltd., 

 Berryhill, Mansfield. 



[The sharp line marks the unconformable junction of the Pebble Beds with 

 the underlying Lower Mottled Sandstone. The line is more evident on 

 the left, where the rock has been newly excavated.] 



may be mentioned here, is the presence of a marked unconformity 

 between the Pebble Beds and the Lower Mottled Sandstone. This is 

 very clearly seen in the huge sand-pit of the Mansfield Sand Co., Ltd., 

 south-east of the town (see fig. 6, above). Here a vertical section, 

 of about 75 feet in all, shows some 45 feet of coarse pink sandrock 

 with occasional pebbles, which are more numerous towards the 

 top, resting on about 30 feet of soft red marly sandrock, quite 

 free from pebbles, but with bands of grit in the lower part. The 



