168 STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 



include many small lenses of bright coal. The dip is from 20 to 70 

 degrees, usually about 40. The ash, as shown by the analyses, is 

 rather high, the samples being prisms from the whole bed. Some 

 of the coal gives a strong coherent coke. On Hat Creek, G. AI. 

 Dawson obtained this section : ( i ) Grayish and brownish shales and 

 sandy clays, with thin layers of lignite, about 20 feet; (2) lignite 

 with shales, shaly and lenticular layers of silicious limestone, iron- 

 stone and shale; the lignite is fairly good, forms about two thirds of 

 the whole and contains much crumbling aliiber, 26 feet; (3) lignite 

 with little impurity, compact below, softer above, 42 feet, with the 

 bottom not reached. 



The lignite of the great mass is without foreign materials aside 

 from irregular masses of calcareous or silicious stumps. Analyses 

 show that the quality is good, there being only 9 per cent, of ash 

 and 8.60 of moisture. 



There are several small areas along the upper portion of the 

 Fraser River; the hgnite is unimportant but G. ]M. Dawson has given 

 some notes respecting the rocks. The material of the upper beds is 

 pale greenish and grayish white, very fine-grained and often a fire- 

 clay; at times it is rich in diatoms. The beds are mostly horizontal 

 but occasionally a local disturbance gives a dip of 20 degrees. Im- 

 pressions of roots and branches are common and two silicified stumps, 

 evidently in place, were seen. The beds turn up around the stumps 

 and thin out toward them. The lignite, at the bottom of the section, 

 is not in well-defined beds but is interstratified throughout with clays 

 and appears to have been deposited as driftwood by somewhat rapidly 

 flowing water ; it is not pure enough to be of any value. Small spots 

 and drops of amber are abundant in some layers. Little is known 

 respecting the extent or importance of the other areas. The field 

 geologists of Canada are in full accord with the palaeontologists in 

 the belief that these widely separated deposits were laid down in lakes 

 or in estuaries. 



The Eocene coals of Alaska have been studied more or less in 



detail during the last 40 years. Dall's'-^* examinations were made 



in 1875, and the essential portions of his descriptions have been 



234 W. H. Dall, "Report on Coal and Lignite of Alaska," Seventeenth 

 Ann. Rep. U. S. Geol. Survey, Pt. I., 1896, pp. 771-908. 



