LLVSSIC ROCKS OF TILE CARLISLE RASIN. 



287 



consists of two great faults, which abut against each other at New- 

 biggin, on the Pctterill. Both faults have a downthrow to the north. 

 The more westerly ranges from a point a little north of Pose Castle, 

 on the Caldew, to Ncwbiggin ; the other from Newbiggin to Bracken- 

 bank, on the Eden, about two miles above the railway bridge at 

 Wethcral. This Brackenbank and J^ewbiggin fault is known to 

 exist for many miles eastward of the Eden ; it has also (as I believe) 

 a considerable extension westward, in the direction of Cummers- 

 dale. 



The Lower Permian beds which are cut off by these faults are 

 the Penrith Sandstone, a bright red rock remarkable for the scale 

 on which it is false-bedded, and a red shaly series overlying it, and 

 directly underlying the St.-Bees Sandstone. The Penrith Sandstone 

 is well shown in the Petterill, a little below "Wreay Bridge. The 

 junction of the Penrith Sandstone with the overlying shaly beds (which 

 in this locality contain gypsum) may be seen in the little streamlet 

 which runs into the Petterill from the east, after crossing the Car- 

 lisle and Penrith road about midway between Springfield and Carle- 

 ton Hill. A little lower down the Petterill, but just above the road 

 from Newbiggin Bridge eastward, there is a quarry in St.-Bees 

 Sandstone. 



North of the faulted line the St.-Bees Sandstone is the only Per- 

 mian rock seen*. About Brampton it occupies a broad belt of 

 country between the Carboniferous formation on the east and the 

 Triassic rocks on the west. In the Eden it is well shown between 

 Brackenbank and Wetheral Bridge, and thence as far down as the 

 junction of the Eden and Irthing. In the Hether Burn, the Line, 

 and Cardwinley Burn sections are very abundant. In the Line the 

 full thickness of the St.-Bees Sandstone does not appear, owing to 

 Carboniferous rocks being brought in by a fault close to Brackenhill 

 Tower, above which spot no Permian beds are seen ; but in the 

 Hether and Carwinley Burns there is an almost continuous series of 

 sections, from Carboniferous rocks below the St.-Bees Sandstone to 

 the Triassic beds above it. In both streams (as in Shalk Beck) a 

 thin breccia is seen at the base of the Permian formation, and there 

 is no fault at the junction with Carboniferous rocks. In the Esk, 

 north of the railway bridge between Scots Dyke and Biddings junc- 

 tion stations, the St.-Bees Sandstone may be seen, on the right bank 

 of the stream, on both sides of the Border-line ; it also appears 

 in Moat Quarry and the cliff on the south side of the railway 

 between Moat Quarry and the ancient fortress known as Liddel 

 Strength. West of the Esk it is visible in the neighbourhood of 

 Scots Dyke, both in the Glinger Burn and Sark ; also in many parts 

 of the Kirtlewater, south of Xirtlebridge. It is well shown in the 

 railway-cutting on the north side of the road from Annan to Kirtle- 

 bridge, in the Annan water about Annan, and at Tordoff Point 

 on the Solway. 



The dip of the St.-Bees Sandstone, which varies, as a general rule, 

 from north to north-west between Maryport and the Caldew, slowly 

 * Except a very thin breccia at its base. 



