8

be ascertained, but judging from the strikes and dips of the rocks to the
north and south it seems fairly certain that the quartzites dip east. Most
of the quartzites weather light brown. The talus consists of rectangular
blocks. Along the strike the quartzites change into black argillites. The
body of quartzite is about 4 miles long and about 2,000 feet thick and may
represent a delta formed at the time that the argillites were being laid down.
North of LeRoy mountain the sedimentary band consists of argillites which
in the eastern half of the band appear to have a uniform dip of 45 degrees
to the east. The thickness may be as great as 2,000 feet. In the western
part of the belt the dip of the argillites changes suddenly from a moderate
easterly dip to a steep westerly dip.

Farther north on East creek the sedimentary band narrows to half a
mile, the rocks are argillites, and the prevailing dip is eastward. From
East creek to the north end of the Theophilus igneous body the sediments
have in general very gentle easterly dips, but over areas a mile or more
wide the rocks are horizontal. There are several isolated areas of sedi-
ments near the north end of the Theophilus body. The sediments appar-
ently underlie a thin layer of volcanic rocks and appear where erosion has
cut through the overlying voleanics. The Theophilus igneous body ends
to the north by changing gradually from stratified tuffs to sediments dip-
ping northeast. These sediments overlie and merge downward into the
northern prolongation of the sediments that underlie the igneous body along
its western side.

The Kitsault igneous body is mainly composed of intrusives, but the
eastern part of the north end of the body consists partly of stratified tuffs
which interfinger with northerly striking sediments. The most westerly band
of these sediments extends several miles. It consists mainly of argillites
that form a northerly plunging syncline and conformably overlie stratified
tuffs. They contain fossils in a zone 200 feet thick immediately above the
stratified tuffs. The band of tuff is underlain on the east by sediments that
are continuous with those that underlie the Theophilus igneous body. The
tuffs of the Kitsault body are, therefore, at approximately the same horizon
in the sediments as are the tuffs of the Theophilus igneous body.

The sediments west of the Kitsault body are split into two bands by
the Klaydue igneous body. The sediments are mostly black argillites, but
beds of quartzite, greywacke, and conglomerate also occur. North of Evind-
sen creek, the strata near the western side of the northern part of the Kit-
sault body dip west at moderate to steep angles which lessen to low angles
a mile to the west. The western part of the Kitsault body in this locality
is formed of fragmental rocks, and tuffs and breccias are interbedded with
sediments in a zone 200 feet thick that dips west under the sediments. On
West creek the sediments dip south and west under the crystalline rocks
of the Klaydue body. South of this the direction of dip is variable.

The sediments west of the Klaydue igneous body are chiefly black
argillites. On Alice arm the sediments near the contact with the Coast
Range intrusives are greatly faulted and the structure is unknown, farther
east the strata exhibit westerly dips. Farther north at Klayduc mountain,
the band of sediments is less than half a mile wide between granite on the
west and crystalline volcanic rocks of the Klaydue body on the east and