THE 



GEOLO&ICAL MAGA.ZINE. 



No. ex.— AUGUST, 1873. 



I. — On the Sukface-Gteologt of the Neighbouehood of Cross 

 Fell, in Cumberland.^ 



By C. E. De Range, F.G.S. 



THE eastern margin of the Vale of Eden, in the neighbourhood 

 of Blencairn, Ousby, and Melmerby, is abruptly terminated 

 by a steep and lofty escarpment, which rises to an eminence of 

 2892 feet at Cross Fell, 2331 feet at Melberby Fell, and 2082 feet at 

 Fiends Fell, the elevations between these points being nearly as 

 great. Eastwards, from the top of the escarpment, a large expanse 

 of elevated moorlands slope gradually towards the North Sea. 



The upper portion of the escarpment consists of successive scars 

 of limestone and grit resting conformably on " Old Eed " Sandstone 

 and Conglomerate, lying in denuded hollows of Lower Silurian 

 rocks, which form the base of the range, and abut against the 

 Permian Sandstone, brought in by the Pennine fault. 



In general aspect the Cross Fell escarpment may be compared to 

 that of the North Downs near Folkestone, the Limestone scars 

 corresponding in a scenic point of view to the Chalk (weathering in 

 very similar curves), the Old Eed and Lower Silurian to the Gault, 

 and the Permian and Boulder-clay plain to that of the Lower Green- 

 sand. 



Near Folkestone lines of springs occur at the base of the Chalk, 

 the overflow of a wedge of water partially held back by the sea, 

 after flowing down the dip of the strata. Springs occur on the face 

 of the Cross Fell escarpment, above impermeable beds of shale, with 

 a similar inwards dip, the overflow probably being caused by the 

 outlets of the water, the lower outcrop of the water-bearing stratum 

 not being suificiently large for the volume of water flowing out into 

 the streams. 



The continuity of the lower escarpment of Cross Fell is broken 

 by several valleys cut back into the breast of the hill, as Ardale, 

 between Muska Hill and High Cap. This valley runs a mile into the 

 hill to a height of 1750 feet, after which the stream flows over a 

 sloping plain and through an escarpment " Black Doo," through 

 which it has cut a V-shaped hollow. 



North of this, nearer Melmerby, is an extremely wild valley, 



1 The notes on the Cross Fell district were chiefly made during a holiday expedi- 

 tion into that country in July, 1872, and partly when in the adjacent country with 

 Prof. Hull, P.R.S., in April of the same year. 



VOL. X. — NO. ex. 22 



