Ins RECONNAISSANCE T X NORTHERN ALASKA IN 190] 



Here the coal is abundant and conspicuous. In the talus at the foot of the blurt's 

 it is strewn about in detached blocks and bowlders ranging from I to several feet 

 in diameter. Its occurrence in place in the blurt's is for the most part in the lower 



half of the section, where it appeal's in half a dozen or more beds that are from 1 to 

 :; or more feet in thickness, ami are eon forma I tie with the Colville series, of which 

 they form members. The beds lie for the most part nearly horizontal or dip very 

 gently northward, and are well exposed for a distance of probably V> or more miles 

 along the river. They are represented by the dark or black layers in PI. VIII. 



The associated rocks, of which a fuller description is given under the head of 

 geology, consist in general of heavy beds of partially consolidated silt, soft shale, soft 

 sandstone, very impure limestone, and intermediate types of deposits. 



So far as observed in ascending the geologic section, the coal layers in most 

 eases are underlain by a heavy bed of soft sandstone or shale 3 to 6 feet thick, with 

 an intervening thin 6 to 8 inch layer of shaly under clay. The shale bed often 

 contains fragmental lignitic plant remains. 



As shown in the table of analysis (p. Hi), where it is indicated by No. 620, 

 the coal seems to be a good quality of lignite, with volatile matter 30.33 and fixed 

 carbon 30.27. As the specimen was considerably weathered, it is probable that the 

 analysis here given may fall somewhat short of representing the average efficiency of 

 the coal. On several occasions the coal was used by the party in camp fires, and 

 gave good satisfaction. It burned readily and yielded considerable heat. 



The coal in general presents a dull-black appearance, and at first appears massive, 

 but on closer observation is found to contain nearly horizontal, more or less discon- 

 tinuous beds and thin layers of highly metamorphosed material, which is of a deeper 

 black and has a somewhat high anthracitic luster. The main bod}' of the coal seems 

 to be composed largely of a mass of similarly well-metamorphosed, short, and glisten- 

 ing needles or spicules, variously compressed together in horizontal arrangement, 

 presenting somewhat the appearance of an imperfect fibrous or wood} T structure. 



From the known occurrence of such lignite and lignitic plant remains in the 

 Kenai (Oligocene) elsewhere in Alaska, and from the position of tills coal in the beds 

 above the Upper Cretaceous and below fossil-bearing Pliocene beds, the coal is 

 inferred to be Oligocene. The vegetable fragments collected from the shale beneath 

 the coal were examined by Doctor Dall, who suggests that they are probably the 

 needles of Sequoia langsolorffii or some related conifer. He also suggests that the 

 mass of this coal is probably composed of the trunks of Sequoia. 



From an economic point of view, it should be stated that this coal is probably 

 not suitable for export or for steaming purposes, and, though it is abundant it is 

 unlikely, from its remoteness, under present conditions of the country, to prove to 

 be of value for local use. It is not difficult of access, however, and could readily be 



