in Nottinghamshire and LincolnsJdre. 253 



soft blue sandstone and blue clays ' at the base of the "Waterstones in 

 this part of the county . . . They are 20 to 25 feet thick, and 

 consist of micaceous ripple-marked pale clays, shales and sandy shale, 

 of grey-green, grey-blue, or sometimes reddish tints, with occasional 

 streaks of gritty sand, calcareous nodules in places, and obscure 

 fragments of carbonized organic matter (probably plants)." 



The greenish colour of the beds is most marked where they crop 

 out at the surface ; in borings the prevailing colour is a bluish-grey 

 or grey. In many cases a thin calcareous conglomeratic sandstone 

 underlies the Green Beds and rests directly upon Eunter sand-rock, 

 but it is impersistent and may be altogether absent. It suggests some 

 slight unconformity between Keuper and Bunter, which is also borne 

 out by field mapping. 



Outcrop. At the surface I have seen the beds as far south as Oxton 

 (Sheet 126, n.s.), within 6 miles of Nottingham, and as far north as 

 iletford (Sheet 101, n.s.). In all probability they could be traced 

 further in both directions, for at Nottingham itself (Colwick Road, 

 Sneinton, Sheet 126, n.s.) the lower "Waterstones contain grey layers 

 and overlie 3 feet of greenish-yellow flaggy sand-rock, which rests 

 upon a thin conglomerate.^ 



Underground Extension. By means of borings they have been 

 traced underground over a much larger area than their mapable 

 outcrop would suggest, i.e. from Owthorpe (Vale of Belvoir, 

 Sheet 142, n.s.) in the south, to beyond Gainsborough in the north 

 and Lincoln in the east. Prom the records of some of these borings 

 a table has been constructed (pp. 254-5) to show the persistence 

 of the Green Beds, and the depth at which the Bunter Pebble-Beds 

 occur in each case with respect to Ordnance Datum (see also 

 Figure, p. 256). 



In certain cases — marked by an asterisk (p. 254) — my reading of the 

 records differs from the published account, the alteration depending as 

 a rule on the occurrence of the Green Beds, which had been overlooked. 

 The upper limits of the beds are often difficult to determine from 

 the published records, chiefly because no attempt had been made to 

 separate them from the more normal Waterstones above. Had it been 

 possible to examine all the cores, the thicknesses given in the table 

 would doubtless have shownless variability. At Owthorpe, Kuddington, 

 Newark, Tuxford, and Southwell, at least, the figures quoted are 

 probably too small, because layers of red marl sometimes occur with 

 grey and blue layers at a higher level. The cores at Clipston and 

 Hampton, which were personally examined, proved the blue-green 

 facies to be fairly thick. At Markham Moor, about two miles north- 

 west of Tuxford, a boring^ (at Mr. Mudford's house) proved 30 feet 

 of blue clay and stone resting upon red Bunter Sandstone (—54 feet 

 O.D.), from which water was obtained as soon as it was struck. 



The Hampton (Criminal Lunatic Asylum) boring for water was of 

 great interest because the normal Keuper Waterstones were remarkably 

 like the Keuper Marls. The characteristic red sandstones were so 



^ Geology of the Country between Newark and Nottingham (Meni. Geol. 

 Surv.), 1908, p. 37. 

 - Borers' record. 



