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have not been tested. He has also noted the great variety of structure
between “the highly folded and faulted mountain structures . . . and the
almost imperceptible undulations of the plains’. Between may be struc-
tures favourable for production of oil or gas.

In the Dunlevy-Portage Mountain map-area, in the eastern part of the
Foothills, Beach and Spivak (1944) suggest that tests for oil be confined to
Triassic and older formations, as all later strata reach the surface. They
note that both the Triassic and Permian beds are marine, but the Triassic
has little porosity and the Permian beds are less consolidated and contain
numerous vugs, some of which are filled with pyrobitumen. They warn
that although the Bullhead anticline is the most favourable in the area for
a test, the east limb is steep and may be faulted. They call attention to
the difficulty of drilling through the hard sandstone and conglomerate of
the Dunlevy formation and state that this might be avoided by drilling in
the preglacial river channel between Portage Mountain and Butler Ridge.

East of the Foothills and north of Peace River, in the vicinity of Farrell
Creek, six holes were drilled in 1922 on the Farrell Creek anticline or dome
(Dresser, 1921, 1922). Beach and Spivak (1944) note that these holes
penetrated the Hasler, Gates, and Moosebar formations, and 800 feet of the
Gething. At a depth of 2,273 feet, apparently in the upper part of the
Gething, 2 feet of tar clay was encountered. Dresser (1922) reported an
oil concentration of 80 gallons a ton. It may be observed that these holes
were not carried through to the Triassic and Paleozoic and so afforded no
test of the oil possibilities of these older beds. Other structures in Peace
River Valley east of the Foothills have not been tested.

Wickenden and Shaw (1943) do not discuss the oil possibilities of the
Mount Hulecross-Commotion Creek map-area, which includes a part of Pine
River Valley. Spivak (1944), however, recommends that drilling tests be
confined to beds below the Gething. He regrets the lack of information
concerning porosity. Indeed too little attention has been given to the
study of porosity of the rocks in northeastern British Columbia.

The Commotion Creek well was carried to a depth of 6,940 feet without
obtaining oil or gas (Hage, 1944). The hole ended in the Bullhead beds,
and appears to have entered a fault zone.

In a search for oil and gas in the Plains, drained by Pine and Peace
Rivers, the comparatively gently undulating structures described by
Spieker, Dresser, Williams and Bocock, and others (See Chapter IV) should
be considered. It may be noted that some of the interpretations of struc-
ture made on the basis of earlier work have been revised in later investiga-
tions; some faulting has been recorded where before only folding had been
recognized.
PEACE RIVER TO MUSKWA RIVER

Hage (1944) has briefly discussed the oil and gas possibilities in the
Foothills and Plains between Peace and Muskwa Rivers. He considers that
the presence of porous and permeable reservoir beds is important. They
may occur at erosional unconformities, especially where limestone has been
subjected to erosion. He does not know whether such beds are in the
Palwozoic group, and suggests that a search be made for them in future
investigations. He calls attention to medium- to fine-grained sandstone in
the Triassic system. No porosity tests, however, were made by him.