YAKUTAT BAY REGION. 63 
narkedly in contrast with the Yakutat series in general lithologic character, in degree of 
nduration, and in the absence of marked folding and faulting, all of which indicate more 
ecent age. Their exact relation to the Yakutat series could not be determined, the con- 
act being hidden beneath glacial debris ; but the two series were traced to within a quar- 
er of a mile of each other. It is probable that they are separated by a fault. 
In one layer abundant plant fossils were found. The collections from this layer have not 
>een studied, but from a hasty examination F. H. Knowlton reports as follows: 
There are six or eight species of plants present, among them being minute fragments of a, conifer; two 
erns, and a number of dicotyledonous leaves. The conifer appears to be a Glypto.strobux or a very slim- 
ier Sequoia. The ferns both belong to the genus Dryopteris, one of them being in beautiful fruit. This 
Brri is hardly to be distinguished from a species now living in Jamaica. The dicotyledons seem very 
nodern in appearance, among them being one beautifully preserved leaf which I am not able at the 
aoment to distinguish from an undescribed species of Sterculia from Pliocene beds of the Cascades of 
Jolumbia River. 
So far as this hasty examination shows, none of the plants is referable to the Kenai, and if the exigen- 
ies of the stratigraphy demand that they should be referred to the Pliocene, there is nothing to con- 
radict it. 
UNCONSOLIDATED DEPOSITS. 
The unconsolidated beds include a complex series of glacial and aqueous deposits. Some 
>f these are being laid down now in the form of moraines along the termini of the glaciers and 
is alluvial fans by glacial and other streams. Some of the deposits were formed during 
arlier advances of the ice. To the latter class belongs much of the deposit making the fore- 
and and also a series of gravels forming cliffs and terraces at various points along the shores 
>f Yakutat Bay and Russell Fiord. These terraces consist of cross-bedded sands and 
winded gravels containing a large percentage of crystalline rocks. Scattered through 
hese gravels is some gold, which, when concentrated by wave action on the beaches, forms 
leposits which are worked in a small way. 
ECONOMIC GEOLOGY. 
Yakutat Bay has been a highway for a large number of prospectors on their way to the 
;old fields of the Alsek Valley. One route was over the Nunatak Glacier; another to 
lie head of Russell Fiord, thence overland to a glacier leading back to the Alsek. Natu- 
ally, therefore, the shores of the fiord have been quite extensively prospected. As a result 
here has been much staking of claims, but no discoveries of important mineral deposits 
lave so far been made. Four substances have been sought here — petroleum, coal, platinum, 
md gold. Each of these will be briefly considered. 
PETROLEUM. 
Definite information concerning the reason for the search for petroleum could not be 
)btained. Probably the principal incentive was the discovery of petroleum farther north- 
vest in a similar topographic situation ; but it is reported that surface indications of oil have 
)een seen, though the present study failed to find any of the localities. Whatever the rea- 
son, the shores of the bay were staked promiscuously, both on the glacial deposits of the 
'oreland and the hard rocks of the mountains. No explorations were made so far as could 
3e learned. 
There seems little reason to suspect the presence of oil here. The glacial deposits of the 
'oreland may of course cover oil-bearing beds, but nothing short of borings would demon- 
strate this. The rocks of the Yakutat series seem unpromising, both because of their bar- 
renness of organic remains and their shattered condition, which would seem to be most 
infavorable for the storage of oil. Altogether the prospect of finding petroleum here seems 
very slight. None of the Alaska oil wells are in rocks of this lithologic character or age. 
