THE CROSS FELL INLIER. oOl 



§ II. Gl]NERA.L BESCKlPriON OP THE InLIER. 



Tho Cross Fell Inlier of Lower Palaeozoic rocks is marked by 

 the occurrence of a ji^roup of pyriiinidal hills, stretchinji; in a band 

 from halt" a mile to a mile in width, for a distance of about 1() miles 

 in a general X.W. to S.Pl direction on the west side of the Pennine 

 escarpment, from a little north of the villa,2;e of Melraorby on the 

 north to the south-west flanks of Roman Fell on the south. It is 

 bounded by two great faults, which enclose it as an elongated 

 spindle-shaped mass. The eastern fracture, which may be termed 

 the Escarpment Fault, brings the Lower Carboniferous rocks 

 against those of Lower Palieozoic age, whilst the western one, the 

 Pennine Fault of tho older writers, and which Mr. Goodchild terms 

 " the Outer Pennine Fault," places the Lower Pala)ozoic rocks in 

 juxtaposition with the New Red Sandstone for many miles. The 

 lenticular inlier between these faults is furthermore broken b}' 

 another great N.W. and S.E. fault, bringing Lower Ordovician 

 rocks on the east side against the Higher Ordovician and Silurian 

 strata of the west. This is " the Middle Pennine Fault " of 

 Mr. Goodchild ; but as a great part of the displacement here was 

 produced at a much earlier date than that due to the other two 

 faults, we consider it better to speak of it as the Knock Pike- 

 Flagdaw Fault, as it is well seen between the two hills bearing 

 those names. It is true that subsequent movement has occurred on 

 this line along part of the course of the fault, so that at the north 

 •end of the Inlier the Lower Carboniferous rocks are included 

 between the Ordovician and New Eed Sandstone deposits, but to 

 the south the fault is seen to pass under the Carboniferous con- 

 glomerates of Roman Fell with little or no disturbance of those 

 rocks, and emerges again on the south-west side of the hill where 

 the Lower Palaeozoic rocks are developed. 



By means of the Knock Pike-Flagdaw Fault the lenticular inlier 

 is divided into an older eastern and a newer western portion, and it 

 will be convenient to describe these separately, commencing with the 

 older rocks which lie to the east of the Knock Pike-Flagdaw Fault. 

 Unfortunately none of the rocks which occur on that side of the 

 fault are seen to the west of it, and consequently a considerable 

 gap occurs in the succession here, though how great it is hard to say. 



§111. Detailed Description of the Strata. 



a. The Eastern Portion of the Inlier. — Most of the sedimentary 

 rocks on the eastern side of the Knock Pike-Flagdaw Fault have 

 been referred to the Skiddaw Slates, but as only few fossiliferous 

 localities have been detected in this area, the correlation has been 

 made to a largo extent from similarity of lithological character. 

 As the evidence furnished by these rocks is at present insufficient 

 to establish a detailed sequence, we shall content ourselves with a 

 fery brief notice of the deposits, for it will be necessary to devote 



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