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Notes on the Geology of the District. 



The proposed route is l)y Midway, Hartshorne, Ticknall, and Melbourne. 

 Along the line of the Ashby Road, in the immediate neighbourhood of Burton, 

 the untlcrlying rocks belong to tlic Keuper, which is the uppermost division of 

 he New Red Sandstone. The Coal Measures come to the surface a little E. 

 of Moat Bank. The line of division between these and the New Red is erro- 

 neously marked in the Survey Maps as a faulted one. The Lower Keuper here 

 lies with a slight N.W. dip upon the upturned edges of the Coal Measures, 

 which, dipping S. and S. W. occasion the outcrop of some of the most imjiortant 

 of the lower seams of coal, within a few hundred yards of the road, and almost 

 parallel with it. 



There arc indications that a small portion of the coal field near Brizlincote 

 Hall cannot have been submerged in Triassic times until a period later than the 

 deposition of the Bunter. This small patch of old Carboniferous land must either 

 have been a promontory, stretching wes'ward from the mainland, then constitu- 

 ting the eastern margin of the early Triassic sea, or, what is far more likely, a 

 small ISLAND which did not become completely suljmerged until the deposition 

 of the greater part of the Lower Keuper sandstones of the neighbourhood. 



At Bretby I'ark Lodge we cross an important line of fault, with a downthrow 

 of 240 feet, to the N.E., the result of this being that the Triassic rocks are let 

 down to a level with the Coal Measures. Of the existence of this fault there can 

 be no doubt, but a somewhat erroneous impression of its results is given by the 

 Survey Map. As a matter of fact, the strata on the W. side of Bretby Park, 

 which are faulted against the Coal Measures, and which can only be reached by 

 the boring rod through Boulder Clay, belong to the Lower Keuper division 

 of the Trias, not to the Bunter. 



A passing reference must be made to the Boulder Clay, which is seen between 

 here and Burton, capping all the hills which rise above the 380 feet contour line. 

 W. of Bretby Park, this consists of a stiff reddish clay full of fragments of 

 Mountain Limestone from the Pennine Range. On the W. side of Bretby Park 

 it consists of a stiff clay containing innumerable small fragments of CHALK, 

 and of Jurassic rocks, all of which must have been derived from the country to 

 the E. of the Pennine Range. This is the true Chalky Boulder Clay, and 

 its occurrence here — which has only recently been observed — is of considerable 

 interest, since it is the first time the Chalky Boulder Clay has been found 

 within the limits of the Ashby Coalfield. 



The Bunter, over which the road now passes, consists of coarse, light-coloured, 

 current-bedded sandstone, with quartzite pebbles. Occasionally, from the in- 

 filtration of calcareous matter, the rock forms a consolidated conglomerate. 

 The surface of the land over the Bunter Pebble Beds is very undulating, and 

 has been carved into roundeil hills and steep-sided valleys, the latter having a 

 N. and S. direction. These valleys — the two most important of which are those 

 running through Milton and Repton— have, in places, been excavated down to 

 the Permian Marls and Breccias. These Permian Marls and Breccias, owing to 

 the fact that they are unconformable both to the underlying Coal Measures and 

 the overlying Bunter, are not always present. Between the period of their 

 deposition and the deiiosition of the Bunter, a consideralile time elapsed, during 

 which the bottom of the Permian Sea was upheaved and the strata much denuded, 

 consequently, in many ]ilaces, the Bunter is found resting directly on the Coal 

 Measures. We have here an interesting case of a double unconformity between 

 three groups of strata; the stratigraphical break, however, between the Coal 

 Measures and Permian is, in our neighbourhood, much greater than that between 

 the Permian and the Trias. This is the reverse of what is seen in the coalfields 

 of N. Staffordshire and Warwickshire. 



Between Hartshorne and Ticknall the road passes over the .MILLSTONE Grit, 

 which rises to the surface from under the coal measures at the N. of the Ashby 

 Coalfield. Repton Rocks, which are sighted a little to the W. of the main road, 

 consist of a picturesque and wooded excavation in the Millstone Grit, forming a 



