344 



ME. J. E. MARK OS LIMESTONE-KKOLLS IN [Aug. I 899. 



any incipient folding : in the second case as the result of folding 

 carried to excess, and the consequent severance of fragments of the 

 rock. In the latter case the breccias are naturally distributed more 

 irregularly than in the former, where the breccia seems to form a 

 true bed, as indeed it is, though, according to my view, in an altered 

 condition. These breccias are apt to occur in the knoll-limestones, 

 while the other kinds are found in the deposits mantling round the 

 knolls. 



Fig. 9. — Limestone-breccia, Draugliion Qaarrif. 



[Eeprocluced from a photograph taken by R. H. Adie, M.A.] 



The reason for brecciation of some limestone-bands while others are 

 ^nbrecciated appears to be illustrated by the state of limestone-bands 

 in a disused quarry on the south side of the Skipton road, just outside 

 the village of Draughton, on the way to Skipton. Here some of the 

 bands of limestone show incipient brecciation, and where the action 

 ha^ not commenced these bands are seen to be affected by verj' close 

 i'Tregular jointing at right angles to the bedding: moreover, they 

 possess lines parallel to the bedding which are either lamination- 

 planes or joints. These limestones would naturally break up into 

 fragments when affected by earth-movement, while the more massive 

 limestones with joints remote one from another might well escape 

 brecciation. 



Breccias of this type are well exposed in the great quarry on the 

 right bank oF Dale Eeck, Ingleton, between the two branches of the 

 Craven Pault. In one place a band between the other beds, which 

 is about 30 feet thick, shows various stages of brecciation. Near 



