106 ALASKAN MINERAL RESOURCES IN 1905. 
. 
At a point marked A on the map (fig. 6, p. 105) a normal fault was observed in the coal 
bearing sandstones, its direction being slightly east of north and its dip 20° E. The down- 
throw, roughly estimated at 30 feet, was to the east, and the disturbed beds could be plainly 
traced on either side. It is noteworthy that this fault occurs in a bluff containing seams of 
coal of considerable thickness. 
On the shores of Herendeen Bay two faults were seen — one on the point south of Moss 
Creek Valley, the other on a point south of Lawrence Creek Valley. While both dip to the 
cast a: steep angles (80° and 60°, respectively), their line of strike is not in exact accord, the 
former- striking in a northeast direction and the latter striking slightly west of north. 
it may be noticed by a glance at the map that the strike of the beds on which these faults 
occur agrees very nearly with that of the beds just south of the coal, though the dips are in 
opposite directions. It seems probable, therefore, that the latter beds occupy the northern 
limb of an anticline, though near the I'rcM , as evidenced by the low dip. In tracing the beds 
southward along the shores of Herendeen Bay a change of dip was observed, first flatten™ 
and then gradually steepening as the faulted beds wen 1 approached. 
('lose folding was not noticed in any portion of the field and only by observation over an 
extended area, as shown above, could evidence of any folding whatever be detected. 
DESCRIPTION OF THE COAL. 
Owing both to t he early date at w hich t he coal field was visited and to the neglected state 
of the workings only a few observal i<»us could be made on individual coal seams. What- is 
said to be the largest and most promising series of beds- those at the Johnson tunnel were 
entirely covered with snow, and all information concerning them was received from those 
who in times past had worked on the property. Measurements of coal beds made by the 
writer were confined to two localities in the big exposure on the left fork and in the con- 
glomerate' at the head of the creek. 
Just below the left fork (see fig. 6, p. 105), at locality No. 1, a drift was run 150 feet along 
the strike (N. 40° E.) on a seam .'U feet thick. The seam was lost and the entrance is now 
caved in. At locality No. 2, at the niout h of t he left fork, a drift was driven on a seam strik- 
ing \. 85° Iv, for 200 feet, when again the coal was lost. As in the first instance the entrance 
had caved. This seam is that from which the Alaska Development Company mined approx- 
imately 500 tons in 1889 and from the coal of which the analysis given later (p. 108) was 
obtained. At locality No. 3 a drift now caved was run on a seam. Xo details could be 
obtained. In sandstone, much jointed and crushed, at locality No. 4, a tunnel was driven 
\. 85° 10. Caving has entirely destroyed the entrance. At locality No. 5 the same condi- 
tion exists. 
By far the most work has been done al the Johnson tunnel, marked J in fig. 0. The fol- 
lowing notes were obtained from a miner: 
A drift was driven approximately X. 50° E. for a distance of 110 feet on a coal seam of 4 
feet 6 inches average thickness. Much crushing was in evidence at this point, and the coal 
was lost. 
Though the tunnel was continued to a total distance of 205 feet from the entrance, no sign 
of the lost seam was found. Moreover, 20 feet from the face a drift for 29 feet to the left, on 
the level, at an angle of 45°, also failed to catch the coal. 
Ninety feet from the entrance an upraise was driven to the right on a slope of 45° up the 
bed. It continued at this angle for 90 feet , when a turn was made and the remainder driven 
vertically to the surface. Forty feet up the raise a drift along the coal in the direction of 
the main drift was driven for 32 feet, when the coal pinched out. 
A horizontal crosscut to the right, 93 feet long, from the fool of the upraise passed only 
two seams each 18 inches thick and a few small stringers. 
Al the mouth of the main drift a crosscut tunnel was driven in the hillside opposite in a 
westerly direction for 100 feet without encountering seams of importance. 
