MIDLAND UNION PRESIDENT'S ADDRESS. 171 



The question of the nature and origin of the Glacial Deposits is so 

 wide and so difficult, that, for piirposes of individual research, it is 

 well to subdivide it. The quartzite pebbles form an easily recognisable 

 division, and now that they have been shown to be fossiliferous, their 

 study will prove highly interesting. 



THE GEOLOGY OF THE NOTTINGHAM DISTRICT. 



The rocks of Nottinghamshire though generally devoid of palajon- 

 tological interest — fossils as a rule being conspicuous by their absence — 

 are yet of interest from the important evidence they furnish as to the 

 stratigraphical relationships of the lower Mesozoic to the upper Palseozoic 

 formations. Exclusive of the post-Tertiary rocks, viz., glacial and 

 alluvial clays, sands, and gravels, the rocks of Nottinghamshire 

 naturally fall into two groups of easterly-dipping formations— the 

 Carboniferous and the post-Carboniferous — which are separated from 

 each other by a clearly detined unconform ability, — an unconformity 

 that is proved by the changing strike of the outcropping coal measures, 

 and by the constantly increasing depth beneath the base of the 

 Permian I'ocks of particular coal seams going east from the Magnesian 

 Limestone escarpment on the borders of Notts and Derbyshire, and 

 which may be seen in surface exposures at Kimberley, five miles west 

 of Nottingham. 



TJie Coal Measures. — The only Carboniferous formations represented 

 in Notts occupy but a small surface area on the western borders of the 

 county, but without doubt underlie the newer rocks of the whole of 

 the county, except perhaps in its southern extremity. The coal 

 measures of Notts are of very great economic importance from the 

 large and constantly increasing supplies of fossil fuel that are drawn 

 from them, and they are destined to become of even greater import- 

 ance in the future. The fossils of this series are almost entirely 

 limited to the ordinary coal measure plants and moUusca, though 

 scanty fish remains, a fossil scorpion and one or two limuloid and 

 other Crustacea, have been found. 



TJie Permian Fortnation. — The lowest of the post-Carboniferous 

 formations consists of the following sub-divisions : — Marl Slates 

 with breccia at base. Lower Magnesian Limestone, Middle Permian 

 Marls and Sandstone, Upper Magnesian Limestone and Upper 

 Permian Marls. The last two divisions are, however, scarcely 

 seen in the county. The limestone is largely quarried for 

 building purposes, yielding a rough-hewn stone well adapted for outer 

 walls, and is also burnt for lime, while the marls are manufactured 

 into bricks and pottery. The magnesian limestone, which dies out 

 finally near Nottingham on the south, from its uniform durability has 

 come to form a very evident dip slope from the high ground overlooking 

 the Derbyshire coalfield ou the west to where it becomes covered by 

 Triassic rocks ou the east. For further information on these rocks, 

 including some interesting speculations as to their probable origin, I 



