martin.] .STRUCTURE OF CONTROLLER BAY REGION. 21 
can be made to thus give the key to the major structure. Unfor- 
tunately the rocks of the Katalla formation are so homogeneous 
throughout that no strata have been so far observed which are char- 
acteristic enough to make the dominant structure evident, and the 
observations which have been made are not abundant enough to deter- 
mine the complete structural relations as suggested for another 
method. 
There appears to be a larger folding, modified by a minor folding, 
that often reveals itself merely as a crumpling in the softer shales but 
which is locally so strongty developed as to obscure the major folding 
There are thus two sets of structural features, one of which reveals 
itself in an east-west and the other in a northeast-southwest strike. 
The first is well shown in the great anticline which is described below 
as extending along the coast at Cape Yaktag; and it again appears in 
some of the exposures of this region, especially along the coast near 
Katalla. Of the second series of folds, those extending in a direction 
from northeast to southwest, one of the most illustrative is the anti- 
cline which apparently extends along the center of the Katalla Valley. 
This is paralleled by a number of other folds east of it in the penin- 
sula between Bering Lake and Controller Bay, one of the most dis- 
tinct being the anticline in the little valley nearest Bering River. The 
central part of the peninsula appears to consist of a succession of 
folds, several of which are exposed in the valley of Burls Creek. 
The structure of this region appears at first sight to be extremely 
complex, the strikes and dips being of almost indescribable irregular- 
ity. More careful studies made during the summer of 1904, have, 
however, shown that part of the irregular outcrops are of large blocks 
which have been displaced by gravity on the steep hillsides, while 
part of them may be assigned to a minor crumpling in the softer beds. 
Others may be due to faulting, but the amount of influence of this 
factor is not known. 
After the irregularities due to the above-mentioned cause have been 
eliminated, the following structural features distinctly appear. The 
prevailing strike is northeast and southwest and the prevailing dip is 
from 35° to 00°. The region between Bering Lake and Controller 
Bay consists of an undetermined number of parallel, closely folded 
anticlines and synclines, with pitching axes of which the average 
direction is N. 35° E. The most plainly developed of these folds are 
the Katalla Valley anticline, the Strawberry Point syncline, and the 
Chilkat Creek anticline. 
The structure of that part of the coal area which was visited by the 
writer is rather simple. The strike is fairly regular in direction 
(northeast and southwest), and the dip is chiefly northwestward. The 
uncertain factor is the total amount of influence of the faults. 
