66 



Man : The Rigidity of North-west Yorkshire. 



whistle, and to it may be due the disturbed state of the Car- 

 bcjniferous rocks in that district. 



How far the rigid block extends in an easterly direction is 

 doubtful. To the north-east, there is considerable folding 

 about the Northumbrian coal-field, but to the south-cast, 

 north of Pateley Bridge, the block sinks beneath the Permian 

 rocks of Ripon, and may occur undisturbed some way east of 

 the outcrop of these rocks. 



We will now consider the geology of the tract of Edenside 

 in further detail. 



This region is a geological syncline, or hollow of an earth 

 wave against the rigid block, w^hich shows proofs of the 

 development of the wave at many geological periods. 



The earUest formation of the fold of which we have direct 

 evidence occurred after the formation of the slate rocks, and 



CZlTR/AS. EZZ3 PERMIAN. SnSijl UPPEI? CARBONIFEROUS, ggt"? CARSON; 

 i22 SILURIANJ E33 COMSTOpj limestone E^^ beds below CON'uMESTonE. E] 



CORE. 



Diagrammatic Section across Edenside. 



before that of the Carboniferous strata, though, as hinted 

 before, a still earlier movement may have taken place before 

 the Lower Palaeozoic slate rocks were deposited. The result 

 of the movement before Carboniferous times was to bend 

 down the Coniston Limestone away from the rigid block, so 

 that older rocks occur to the east of it, and newer ones to the 

 west. The older rocks reappear in the Lake District, so that 

 the Coniston Limestone must come up again from beneath the 

 newest slate rocks on the east side of the Lake District ; that 

 is, on the w'est of the Edenside tract. This geological trough, 

 having been once formed, continued to give along much the 

 same lines again and again. We find the Carboniferous rocks 

 bent down in the same manner as the Coniston Limestone, to 

 the east of Edenside, between Milburn and Melmerby, and 

 they again rise up on the west side of Edenside, so that newer 

 Carboniferous rocks came to the surface in the middle of this 

 depressed tract near Appleby. That this movement was 



Naturalist 



