PETROLEUM AT CONTROLLER BAY. 95 
[nearest visible rock is steeply dipping conglomerate, which outcrops 
la few feet away, but the oil can be seen only on the surface of the soil, 
jthe direct source not being visible. 
The upper part of the valley of Burls Creek contains many seepages 
at which the oil oozes directly from steeply dipping shales that here 
contain a large amount of glauconitic grains, making the rock green. 
(Large calcareous concretions are abundant, and many of them take 
the form of septaria nodules with calcite fillings. Organic remains 
are frequently seen in the concretions. The soft shale is also rich 
in organic material, some beds being so dark as to suggest in appear- 
ance impure coal. No coal was seen by the writer in the vicinity 
or anywhere else in these rocks. The rocks seem to be very strongly 
impregnated with oil in this locality and seepages are. numerous, but 
large surface accumulations are rare. Broken shale recemented by 
(ferruginous material was seen here as on Redwood Creek. 
Some seepages with considerable surface accumulation of oil were 
[seen along the edge of the tidal flat close to the wagon road halfway 
between Burls Creek and the mouth of Bering River. Outcrops 
i|were absent in the immediate vicinity, but fragments of shale indi- 
cated the presence of such rock. 
Several seepages have been reported from ChilK&t Creek. The 
largest one seen by the writer is in the west bank of the creek, 1 h 
Imiles above the forks of the wagon road. The oil reaches the surface 
through soft brecciated shale with a steep westerly dip. The seepage 
is associated with a black sulphur spring. 
Many seepages have been reported in the group of hills centering 
around Mount Nichawak. Those seen by the writer were small, but 
the oil issued directly from the rock, which is shale resembling that 
at the seepages west of Bering River. Others are reported to be 
located on the banks of a small lake that is said to be covered at times 
with oil. 
Other seepages have been reported from various parts of the Con- 
troller Bay region, but they have not been seen by the writer. Refer- 
ence should be made to those in the vicinity of Cape Yaktag, about 
75 miles east of Controller Bay. The amount of oil is said to be very 
large, the flow being continuous from several of the seepages, one of 
which has been estimated to yield several barrels of oil per day. The 
oil is said to come directly from the rocks, which are shales and sand- 
stones of Miocene age, and to come from a line of seepages located 
along the crest of an anticline parallel to the coast. 
Inflammable gas comes to the surface of the water in large amounts 
in several places. The largest of the ' 'gas springs" seen by the writer 
are in Mirror Slough and in Katalla River. The former is sufficient to 
furnish a large continuous flame. The composition of the gas is not 
known. It issues from the mud on the bottom of the slough. 
>-& j 
