<<>u in:.] NULATO PROVINCE, PICKART MINE. 49 
From comparison with similar sandstones seen in the Colville River 
drainage that year, Schrader came to the conclusion that the sand- 
stones of the upper Koyukuk are probably of Upper Cretaceous age. a 
The coal bed at Tramway Bar is described as having a thickness of 
nearly 12 feet, the middle 9 feet being comparatively pure lignite. 
The following analysis was made of a sample collected by Schrader 
at this time: 6 
Analysis of coal from bed at Tramway Bar. 
[Analyst, George Steiger, U. S. Geol. Survey.] 
Per cent, 
Moisture 4. 47 
Volatile matter 34. 32 
Fixed carbon 48. 26 
Ash 12.95 
100. 00 
Fuel ratio 1. 40 
The coal does not make a coherent coke. From this analysis it will 
be seen that this coal should be grouped with the bituminous coals of 
the lower Yukon. The coal bed is practically undeveloped, but the 
coal has been locally used to some extent for blacksmithing purposes. 
Pickart coal mine. — This mine, one of the oldest on Yukon River, is 
located 10 miles above Nulato, on the right bank, and 12 miles below 
Koyukuk River. Below the Koyukuk the Yukon flows nearly west to 
within a mile of the coal mine; then it turns abruptly to the south and 
follows along the foot of a series of sandstone bluffs, in which the coal 
is contained, and which are almost continuous to Nulato. 
These sandstones carry plant fossils which have been referred to the 
Upper Cretaceous. At the coal mine these are probably fresh-water 
deposits, but they rest conformably on marine sandstones carrying 
abundant fossils, also referable to the Upper Cretaceous. The coal 
bed at the Pickart mine is stratigraphically about 75 feet above the 
contact of the marine and fresh-water beds. The sandstones between 
the coal beds and the marine beds are continuously exposed and show 
considerable cross bedding, but no evidence of unconformity or fault- 
ing. Above the Pickart coal there is a great thickness of sandstone 
carrying fossil plants, and one small coal seam. About 1 mile up 
the river fragments of sandstone carrying marine fossils of Upper 
Cretaceous age were found, which probably came from the sandstone 
overlying the coal bed, though they were not traced to their bed-rock 
source. These sandstones are exposed continuously along the river 
for 1 mile above the coal mine. In this distance the strike and dip 
frequently change, and there is probably some faulting as well as fold- 
ing. Along this stretch the cliff face rises about 100 feet above the 
a Schrader, F. C, A reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey No. 20 
(in press). 
b Coal Resources of Alaska, p. 565. 
Bull. 218—03 4 
