Ixxxvi 



PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [May 1906, 



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Assuming, therefore, that the plane 

 of deposit of the Rhaetic beds was 

 originally horizontal, the junction be- 

 tween Rhaetic and Triassic rocks, if 

 they had been affected by uplift in one 

 direction and no denudation had taken 

 place, would be high above sea-level 

 near Carlisle. Nevertheless, we actually 

 find Rhaetic deposits to the west of 

 Carlisle nearly at sea-level. How did 

 they get there ? In order to answer 

 this Question, let us consider the outcrop 

 of the Rhaetic in the northern part of 

 our island. The outcrop, on the whole, 

 passes southward from near Middles- 

 borough through Yorkshire, Lincoln- 

 shire, and Leicestershire, parallel to the 

 trend of the Pennines. But, on the 

 other side of the Pennines, almost due 

 south of the Carlisle outlier of Rhaetic 

 deposits, is another occupying a tract of 

 country east of "Wem and Whitchurch 

 in Shropshire ; and these outliers occur 

 in the tract of country which, apart 

 from the Lake-District dome, is occu- 

 pied by a continuous belt of New-Red- 

 Sandstone rock. 



If, then, the rocks of these outliers 

 were originally deposited at the same 

 level as the contemporaneous rocks of 

 the main outcrop, and as they are still 

 much at the level of the rocks of that 

 outcrop, the original plane on which 

 the Rhaetics were deposited must have 

 been deformed by an anticlinal fold, or 

 by a fault, to carry part of it over the 

 present top of the Pennine range. 



The St. Bees Sandstone abuts against 

 the Lower Palaeozoic and Carboniferous 

 rocks at the Pennine Pault ; so there 

 has evidently been movement along that 

 fault since the formation of the St. Bees 



