391 
J^'OTES ON A JUNCTION OF COAL MEASURES AND MILLSTONE GRIT 
AT HAWKESWORTH QUARRY, HORSFORTH. 
BY ARTHUR R. DWERRYHOUSE, D.SC, F.G.S. 
(Read 20th February, 1908, Manitscript received 
20th February, 1908.) 
Over a considerable tract of country, from the neighbour- 
hood of Thorner to Horsforth, the Yorkshire Coalfield is cut off 
to the north by a fault, or series of f?.ults, which brings in the 
Millstone Grit. 
To the north of this line of fault there are several outliers 
of Coal Measures which exhibit the normal junction with the 
Millstone Grit. 
These are at Chapel Allerton, Hawkesworth Quarry, Rawdon, 
and BaiJdon, and it is in one of these, viz., at Hawkeswortli 
Quarry, that the exposure described in the present note occurs. 
The section in the quarry is continued to the neighbouring 
railway cutting and shows the Coal Measure shales dipping to 
the southward and resting upon the " Rough Rock," the upper- 
most member of the Millstone Grit series. 
Both the shales and grits are quarried, the former for brick- 
making and the latter being an excellent building stone. 
In the course of the removal of the overlying shales, the 
surface of the Millstone Grit has been exposed over a consider- 
able area, and during a recent visit of the members of the Leeds 
Geological Association I noticed that this surface presented a 
very curious appearance, consisting of a number of hummocks, 
flat on the top, with steep sides, and separated from one another 
by hollows, which on investigation I found to be old water 
channels. 
The whole surface resembled in a striking manner the 
sandbanks which form the submerged delta of the Mersey, and 
which are exposed at low water of spring tides. 
The deposition of mud followed the formation of the 
channels immediately, as otherwise the outlines of some of the 
smaller runnels must have been obliterated. 
