J. Shipman — Bunter Conglomerate. 497 
II. — Conglomerate at the Base of the Lower Keuper. 
By J. Shipman, Esq. 
R ECENT excavations for buildings on tbe east side of Notting- 
ham have afforded opportunities for observing the true character 
and development of the conglomerate at the base of the Lower 
Kenper, whicli did not exist when tliis district was visited by the 
Government Geological Survey. The fact that no fair equivalent of 
the Muschelkalk of Germany has been met with in England lends 
an interest to the beds at the junction of the Lower Keuper and the 
Upper Bunter which they would probably not otherwise possess. 
Thus the Geological Survey paid special attention to the scanty 
exposures of tliis junction that happened to exist twenty years ago 
in this part. The best section to be seen at that time, near Notting- 
ham, was in a lane leading from the Mansfield turnpike road, a mile 
north of the town, to the Mapperley Hills, and is thus described by 
Mr. Aveline in bis memoir on the Nottingham district (Sheet 71, 
N.E.) : — “ Near the bottom of the lane there are beds of coarse 
sandstone [Upper Bunter] slightly Consolidated, with pebbles of 
various coloured quartz, quartz-rock, and other sandstones. There 
is no good bedding visible in this conglomerate, and lying on it 
there are tliin and regularly-bedded fine sandstones of a red colour. 
This is the bottom of the Lower Keuper beds, and the line between 
the two formations is well marked, there being an apparent uncon- 
formity. There is about twelve feet of this red sandstone, and above 
it three to four feet of soft red loam, tlien a thin bed of coarse light 
sandstone, above this a bed of sand and marl, with some small 
pebbles of quartz, then alternations of dark and light-brown soft 
sandstone of various tliickness, and red marly shale, which pass up 
into the Upper Keuper red marly shale with thin beds of white 
sandstone.” Between the Bunter conglomerate beds and the “ thin 
and regularly-bedded fine sandstones ” there comes a thin bed of 
conglomerate encrusting the slightly eroded surface of the former, 
which Mr. Aveline does not appear to have noticed, or, if he did, 
probably took it to form part of the Bunter. The only conglomerate 
Mr. Aveline appears to have seen was some sixteen or seven- 
teen feet above the base of the Keuper. This conglomerate, liow- 
ever, although traceable all over the Keuper area east of Nottingham, 
consists of merely a few quartz-pebbles imbedded in yellow or 
greenish-white sandstone, never more than eight inches thick, and, 
unlike the conglomerate at the base, is not calcareous. It was not 
until two or three years ago that, discovering the calcareous nature 
of what had been always regarded as the top of the Bunter, I was 
led to exainine the junction at other spots. Since then the furtlier 
opening up of the ground along the line where the Keuper begins 
to overlap the Bunter has enabled me to collect tolerably complete 
data as to the development of the conglomerate in this neighbourhood. 
It may be here mentioned that Chemical analysis has shown that the 
matrix contains a very large proportion of magnesia as well as lime. 
Generally the conglomerate is found to occupy the slightly angular, 
HECADE II. — VOL. IV.— NO. XI. 32 
