24 FAIRBANKS AND RAMPART QUADRANGLES. 
During 1907 additional material was obtained and referred to Dr. 
T. W. Stanton for determination. The following is quoted from his 
report : 
While the fossils are fairly well preserved, they have been considerably dis- 
torted, so that it is not practicable to make specific determination. The better 
preserved forms appear to be undescribed. The following list will show the 
forms recognized in each lot : 
4278. 7 AP 271 (Spur of Wolverine Mountain). 
Hemiaster? sp. Lucina sp. 
Pecten sp. Pleuromya sp. 
Inoceramus of. labiatus Schloth. Pachydiscus sp. 
Cuoullsea sp. Pachydiscns V sp. 
4279. 7 AP 278 (Ridge on left limit south fork of Quail Creek). 
Hernia sterV sp. Pachydiscns sp. 
Oucullsea sp. Pachydiscus? sp. 
4280. 7 AP 279 (Right limit south fork of Quail Creek). 
Pachydiscns sp. 
These fossils evidently all belong to practically a single horizon which is 
confidently referred to the Upper Cretaceous. * * * The species of Ino- 
ceramus is very likely one that has been previously found on the Yukon, but 
the specimens in the present collection are too imperfect to serve as the basis 
for a positive identification. The most important forms are ammonites, which 
make up the bulk of the collection and which I have referred, in some cases 
doubtfully, to the genus Pachydiscus. These are unquestionably Upper Creta- 
ceous types. 
These Cretaceous rocks have been abundantly intruded by dikes 
of granular igneous rocks of intermediate composition that are de- 
scribed below and, furthermore, are much seamed witli small quartz 
veins, many of which are ferruginous. 
CENOZOIC ROCKS. 
TERTIARY. 
Rocks determined as Kenai (Eocene) occur along the Yukon above 
Rampart and are found also for a short distance up the valley of 
Minook Creek, where they contain a small amount of coal. They 
are conglomerates, sandstones, and clays resting unconformably upon 
the older rocks. In some places they are hardly consolidated suffi- 
ciently to withstand the pick, and prospect holes have been sunk into 
this formation under the impression that the material belonged to 
the stream deposits. These rocks are tilted but otherwise are little 
changed. The same formation is found in considerable areas south 
of Tanana River (see PL I), where it carries some good lignitic coal 
seams. 
