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DETAILED DESCRIPTION
Satya Fault

The Saiya fault, with a mapped length of 15 miles, extends south-
easterly from near Saiya Lake across Omineca River, and probably across
Yuen Creek 2 miles from Omineca River. Its extension in either direction
is obscured by drift, and the dip of the fault is not known. Throughout
most of its mapped length the fault separates northeasterly dipping Sustut
strata to the southwest from older, in part northeasterly dipping, Takla
formations to the northeast. The rocks on the northeast side of the structure
thus appear to have moved upwards relative to those on the southwest
side. Brecciated, rusty Takla rocks, cut by a network of white veinlets,
mark the fault about 5 miles southeast of Saiya Lake, and nearby Sustut
beds display many narrow fractures, some of which are polished as though
by differential movement. At Omineca River, about 34 miles upstream from
the mouth of Yuen Creek, Sustut strata are exposed within 200 fect of
Takla volcanic rocks, and the intervening drift-covered area is thought to
mantle the fault zone. As the fault is approached from southwest to north-
east the dips of the Sustut beds change from northeast, through gentle
southwest, to about vertical at the edge of the drift mantle, as if dragged
by the northeast side of the fault moving relatively upwards or towards
the northwest.

Carruthers Fault

The Carruthers fault trends about northwest along the southwest side
of the Sikanni Range for a mapped length of about 13 miles and passes
about a mile southwest of Mount Carruthers. It involves northeasterly
dipping strata of the Takla and Asitka groups, the older strata lying north-
east of the fault. Here, again, the northeast block appears to have moved
relatively upwards. Southeast for 6 miles from the ridge 1 mile west of
Mount Carruthers the fault is marked by a band of buff weathering,
flaky, carbonate-sericite-chlorite schist, 200 to 500 feet or more wide, in
which the folie strike northwesterly and dip about 60 degrees northeast.
Seven miles west-northwest of Mount Carruthers the fault zone outcrops
as several hundred feet of thoroughly fractured and slickensided pale green
rock cut by numerous quartz stringers. The displacement in this vicinity
must have been considerable, as testified by the contiguity of upper Takla
and Asitka formations, with the omission of at least the lower division of
the Takla group. The fault was not observed farther northwest, but it
may be concealed by the drift- and lava-filled depression extending towards
the mouth of Asitka River. Although traversing a terrain of considerable
relief, the trace of the fault at the surface appears to be nearly straight,
and presumably the fault plane has a steep dip.

Ominicetla Fault

The Ominicetla fault, so far as known, is entirely concealed by drift.
It is believed to trend northwesterly along the northeast side of Ominicetla
Creek and thence to extend northerly across Omineca River to terminate
at the Omineca fault. Its possible southeasterly extension or extensions
have been mapped in the adjacent Takla area (Armstrong, 1946). The
fault involves formations of mainly the Takla and Cache Creek groups,