340 



FURTHER PROOFS OF THE FLOW OF THE TRENT 

 ON THE KEUPER ESCARPMENT AT GAINSBOROUGH. 



F. M. BURTON, F.L.S., F.G.S. 



That a river once flowed on the top of the Gainsborough 

 escarpment, which could, to all appearance, have been none 

 other than the Trent, I have shown in ' The Shaping of Lindsey 

 by the Trent.'* Since the publication of this work I have met 

 with further proofs bearing out and confirming this view. 



To make the matter clear it will be well to recall the position 

 and status of the Trent at the time it ran in this old course. 



The mean level of the Trent near Gainsborough is about 

 twenty feet above O.D. The Keuper escarpment on the east 

 of the town is eighty feet higher than the river, or about one 

 hundred feet above O.D. When the escarpment was consider- 

 ably higher than it is at the present time, a subsequent stream 

 of the Humber captured the Trent somewhere about, but 

 considerably higher than the region of Newark, and turned 

 that river from the ' Lincoln Gap,' through which it formerly 

 flowed, into its present course. 



At the time of the capture the Trent valley had no existence, 

 but it was carved out at a later period by the Trent, as that river 

 gradually cut through the soft yielding marls of the Keuper 

 on the west, thus leaving the hard Upper Keuper rocks standing 

 out, and forming the present-day escarpment, which runs, 

 with some few breaks in its continuity, from Hardwick Hill on 

 the north, to Xew^ton Cliff, and beyond, on the south. 



The land on the summit of the escarpment at Gainsborough 

 rises a little as we proceed eastwards, and attains a height of 

 one hundred and twelve feet above O.D., after which it slopes 

 gradually away to the Lower Lias clays beyond ; and on this 

 slope, in a field which has recently been drained, I met with 

 distinct traces of a river bed, exactly like the one I have before 

 described, agreeing with it in all respects, both as to its level 

 and its contents — quartz, quartzites and sandstones — all of 

 which are smoothed and rounded by river action, and imbedded 

 in a matrix of yellowish clay. 



The river in this locality probably ran, at the time, in two 

 channels, separated from each other by about seven hundred 

 yards — one on the present brink of the escarpment, and the 



* See 'The Naturalist,' 1907, p. 261. 



Naturalist,. 



