226 PETROLEUM IN THE NORTH-WEST TERRITORIES. 



locality for petrolenm is met with on this river ten miles from its 

 junction with the main Athabaska, at which distance, Professor 

 Macoun says, " the men pointed out a tar-spring in the stream, at 

 which they very often got tar." 



He also states that tar oozes from the black shales, 150 feet thick, 

 at the forks of these two rivers. Sir John Richardson says these 

 shales are underlaid by soft limestone, " which forms the banks of 

 Athabaska River for thirty-six miles downwards " (from the forks). 

 " The beds vary in structure, the concretionary form rather prevail- 

 ing, though some layeis are more homogeneous and others are stained 

 with bitumen." Limestones, occupying a similar position, re-appear 

 on the Peace River near the oil-spring, already' referred to, and are 

 there described by Professor Macoun as " almost wholly made up of 

 those bi'anching corals (Alveolites) so common in Devonian rocks, 

 intermixed with a species of Zaphy-entis in great abundance, some of 

 the higher strata being largely made up of these." When at a part 

 of the river about midway between the foi'ks and Athabaska Lake, 

 a distance of about one himdred miles, the same gentleman remarks : 

 " I found below a light grey sandstone, partly saturated with the tar, 

 and overlying this, there was at least fifteen feet of it completely 

 saturated, and over this again, shale lai^gely charged with alkaline 

 matter. This was the sequence all the way, although at times there 

 was much more exposed. Where we landed the ooze from the bank 

 bad flowed down the slope into the water and formed a tarred sur- 

 face extending along the beach over one hundred yards, and as hard 

 as iron ; but in bright sunshine the surface is quite soft, and the men 

 when tracking ''along shore often sink into it up to their ankles." 

 Sir John Richardson says : '^About thirty miles below the Clear- 

 water River the limestone-beds are covered by a bituminous deposit 

 upwards of one hundred feet thick, whose lower member is a con- 

 glomerate having an earthy basis much stained with iron and colored 

 by bitumen. * * Some of the beds above this (conglomerate) 

 stone are nearly plastic from the quantity of mineral-pitch they con- 

 tain. Roots of living trees and herbaceous plants push themselves 

 deep into beds highly impi-egnated with bitumen ; and the forest 

 where that mineral is most abundant does not suffer in its growth. 

 * * Further down the river still, or about three miles down the 

 Red River (of the Athabaska), where there was once a trading 

 establishment, now remembered as ' La Vieux Fort de la Riviere 



