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The upper and conglomerate bearing part, with thin coal seams, is
of non-marine origin. ‘The lower part may be of marine origin, like the
Monteith, Beattie Peaks, and Monach formations in the western sections
of the Foothills, but no definite evidence of origin is yet available.

Gething Formation

The Gething formation, in the eastern Peace River Foothills, has
received considerable attention from geologists because of its coal seams.
It has been studied by Galloway (1913), McLearn (1923), Williams and
Bocock (1932), Beach and Spivak (1944), and McLearn and Irish (1944).
It is particularly well exposed in Peace River Canyon (Sce Plate VI B),
where it has been studied in detail. It also occurs on the east slope of
Portage Mountain, the east side of Butler Ridge, in Dunlevy Valley, and
on Mount Gething.

The Gething overlies the Dunlevy formation conformably, the plane of
demarcation being drawn where conglomerates and coarse sandstones
become rare or disappear, and fine sandstone, shale, and coal seams become
more common; this change may not everywhere take place at the same
stratigraphic horizon. In Peace River Canyon, the Gething formation has
been estimated to be more than 1,400 feet thick.

Many different kinds of sedimentary rocks comprise the section of this
formation exposed in Peace River Canyon (McLearn, 1923). The shale
beds are 2 inches to 10 feet thick; some are grey to black and have a shaly
structure; others are black and carbonaceous and are fissile; still others are
arenaceous. Clay ironstone occurs both as concretions and as thin or
thick continuous layers in the shales. Thick zones of thin-bedded siltstones
or very fine sandstones (flagstones) form layers 1 inch to 5 inches thick,
and, here and there, are interbedded with dark grey shales; the latter occur
as very thin beds and may show well-defined mud-cracks. Many of the
flagstones show symmetrical ripple-marks. Beds of sandstone, from about
1 foot to 12 feet thick, vary from fine to coarse, and from massive to banded;
some are crossbedded on a large scale; some are argillaceous, some car-
bonaceous or micaceous; the colours are white, cream, pale yellowish,
yellowish grey, dark grey, and brown. Thicker beds or zones of sandstone,
from 15 to 25 feet thick, in the lower part of the Gething formation persist
for more than 2 miles in the upper part of Peace River Canyon and have
been mapped as members (McLearn and Irish, 1944; and Figure 10).
They include several kinds of sandstones—massive, evenly bedded, cross-
bedded, coarse to fine grained, and here and there may carry lenses of
conglomerate. Commonly they rest with slight erosional unconformity on
subjacent beds due to the removal of a foot or more of sediment prior to
the accumulation of the sand.

Various plant remains are found in the Gething of the Peace River
Canyon section: fronds, stems, fine woody fragments, large pieces of wood,
‘drift wood’, tree trunks lying prostrate along the bedding, vertical rootlets,
and, rarely, upright ‘stumps’. The coarser remains are in the sandstones.
Identifiable plant remains are those of ferns, cycads, conifers, and a single
seed, apparently allied to that of the living gum or Nyassa (Bell, 1944).

Shells, probably non-marine, are rare. They are poorly preserved and
indeterminate.