THE UNDERGROUND WATERS OF NORTH-WEST YORKSHIRE. 
lY. Report of the Geological Sub-Committee. 
by percy f. kendall, f.g.s. ; j. h. howarth, f.g.s. ; 
and w. lower carter, m.a., f.g.s. 
Geological Structure of the District. 
The Carboniferous rocks exposed in the area present the 
following vertical succession, according to Tiddeman : — 
Southern or Bowland 
Type. 
Feet. 
Feet. 
Northern or Yoredale 
Type. 
Millstone Grits ... 
3,900 
Millstone Grits. 
Bowland Shales 
300-1,000 
^ 1 
1 ^ 
Pendleside Grits 
400-900 
Yoredale Series. 
(inconstant) . . 
0-250 
e6 
Pendleside Limestone 
u 
O 
(with Knoll-Reefs) ... 
0-400 
400-800 
The Carboniferous 
Shales with Limestone 
2,500 
i 2 
Limestone (with con- 
Clitheroe Limestone 
3,250 
glomerates at the 
(with Knoll-Reefs) ... 
No base. 
The 
base). 
On the northern (upthrow^) side of the North Craven Fault 
the Carboniferous Limestone is seen to rest upon the Silurian 
Slates and Grits. The recent paper of Mr. Marr (Quar. Journ. 
Geol. Soc, Vol. LV., p. 327) offers a correlation of the beds 
differing somewhat from this, but for the present purposes the 
classification offered above may be accepted. 
The general dip of the rocks is to the north^vard, but there 
are minor undulations which will be mentioned. Restricting 
attention to a tract of country about tAvo miles from east to 
west, by four miles from north to south, and having Malham 
approximately as its centre, w^e find three regions separated by 
the northern and middle branches of the Craven Faults. The 
northern area consists of the white limestones of the lower part 
of the Carboniferous series resting upon Silurian Slates and Grits 
which form a narrow outcrop down to the northern fault. The 
median belt consists wholly of the Carboniferous Limestone and 
forms a high plateau, cut off on the south by a great indented 
