T1IK TlMASSir SYSTKM 



and is about 500 feet thick ; the latter (Red Marls) are estimated 

 at 950 feet. 



The Kirklinton sandstone is only seen in the eastern part <>t 

 the basin, its outcrop elsewhere being concealed by the Drift 

 deposits. It consists of soft sandstones, which are in some part.- 

 re- 1, in others white, or sometimes mottled red and white, and they 

 are probably the equivalents of the Cheshire " waterstones." 



The Keuper marls are also for the most part buried beneath 

 Drift, Imt near Carlisle the sandstones are covered by red and grey 

 marls, which are exposed in several places on the banks of the 

 Eden. West of Carlisle there is believed to be a fault of consider- 

 able magnitude, for borings have shown that a great thickness of 

 red shaly marls with gypsum and rock-salt is brought into the 

 wi-stern and deeper part of the basin.-' 



Keuper marls also occur beneath the northern part of the Isle 

 of Man, borings having proved a thickness of 557 feet with 21 

 of rock-salt, one of these being 16 feet thick. Below are 800 

 feet of sandstone, part of which is probably also of Keuper age. 



In Ireland the largest area of Trias occurs in the valley of the 

 Lagan, and extends from Lurgan to Belfast, and thence along the 

 northern shore of Belfast Lough as far as Black Head. The beds 

 are also seen at intervals along the coast to the northward as far as 

 Red Bay near CushendalL They are thickest in the southern part 

 of the area near Belfast. Rock-salt is found at Carrickfergus, 

 where the general succession is as follows : 



| Red marls with gypsum ..... 700 

 ivruit.i- Rock-salt and blue clays ..... 150 



( Brownish sandstones . . . perhaps 20 



o /Soft red and yellow sandstones with grey 



er l and buff shales 800 



Writing of the Trias in the Isle of Man, Professor Boyd 

 Dawkins remarks that " the unexpected presence of the Saliferous 

 Marls is a link uniting the Triassic strata of the north of the island 

 with those of Barrow on the one hand, and Carrickfergus on the 

 other. It is very probable that these three salt-fields belong to 

 one great saliferous basin underlying the Irish Sea, extending south 

 ward and easlwanl to join that of Fleetwood [in Lancashire], and 

 to the south in the direction of the great salt-field of Cheshire." 10 



4. Mendip and Bristol Cliannel Area 



It is convenient to deal separately with this area because its 

 connections with the areas to the north and south are narrow, and 

 because it exhibits a somewhat peculiar local fades of the Keuper. 



