27 
THE STRUCTURE OF SOME CRAVEN LIMESTONES. 
BY ALBERT WILMORE, F.C.S., F.G.S. 
(Read March 1st, 1906.) 
PART I. 
The Limestone Rocks which this paper deals with occur in 
the antichnal system of the Craven Lowland country. The 
district is somewhat triangular, having Clitheroe, Skipton, and 
Hellifield at the angular points. 
This interesting district has a physical geography very 
different from the district north of the Craven Fault systems 
which bound it on the N.E. side, and which may be termed 
the Craven Highlands. It nowhere rises to more than about 
700 feet above sea level, and is singularly uniform in its general 
aspect. Low, well-rounded hills, with contour lines marking 
series of concentric circles, and with the valleys betv/oen them 
more or less filled with confused alluvial and glacial drift, occupy 
ahnost the whole district. 
In the south-eastern part of the district there is a simple 
dissected anticlinal — the well-known Clitheroe anticlinal — with 
the dip and the strike on the whole very uniform on the S.E. 
side facing the Pendle range of grit hills, but with numerous 
faults and rolls on the N.W. side. Quite sharply contorted 
beds with faults occur at Sawley Grange, Foxley Bank, Grindle- 
ton, and West Bradford Brook (see Plate I., Fig. 1). On the 
south-eastern side of the anticlinal massif there are four or five 
prominent knoll-like masses, three of them forming prominent 
peninsulas, one a well-marked cape, a-nd one an island in the low 
ground of Pendleside shales (shales with limestone of the Survey), 
much of which is covered with glacial drift. These knolls — 
fine examples of the Reef-knolls of Mr. Tiddeman — have been 
the subject of much discussion, and it is proposed to refer to them 
in a later part of this paper. 
The simple anticlinal of Clitheroe and Chatburn becomes 
a much more complex system when traced east towards Skipton 
