A PERMIAN CONGLOMERATE BED AT MARKINGTON. 
BY REV. J. STANLEY TUTE, B.A. 
There is in the parish of Markington a small bed of Permian 
Conglomerate, the existence of which seems to be worth recording. 
It consists of waterworn pebbles of Carboniferous Limestone and 
Sandstone, with angular fragments of Magnesian Limestone, embedded 
in a matrix of harder Magnesian Limestone. The thickness of this 
bed, where it is exposed, is about a yard, and its width a few yards, 
as far as it is traceable. The difficulty of tracing it further arises 
from its position. It occurs a little below the top of a steep bank 
about 50 feet in height, overgrown with a rather dense plantation, 
in which two out-crops appear. This conglomerate bed and another 
well-marked bed, upon which it lies, reaches to the bottom of the 
valley ; and upon its eroded surface there runs the Markington Beck, 
a great part of which shortly disappears in swallow-holes and crevices 
of the Limestone. After passing underneath the hill, which is 
between Markington and Bishop Monkton, the stream bursts out in 
the latter parish. 
That this conglomerate bed once extended further to the west is 
clear from the occurrence there of boulders of this rock among the 
other boulders of the drift. There is clear evidence at hand that the 
loss by denudation has been very great, probably to the extent of 
200 feet or more. The well-marked limestone I have mentioned is 
easily recognized amongst the other Permian beds, and consists of 
smoothed lumpy blocks of greyish-brown limestone, containing many 
sparry cavities, and probably represents the Lower Limestone of the 
county of Durham, the beds of which are described by Mr. Howse as 
" thii'. hard, and knobby, and the entire thickness fissured and inter- 
sected with numerous perpendicular fissures or backs."* It occurs 
also.half-a-mile to the east, near Wormald Green, in a very fine sec- 
tion 200 yards in extent, as a bottom bed ; but I have failed to 
detect any traces of the conglomerate bed there. The section is 
* A guide to the collections of Local Fossils in the Museum, Newcastle. 
