82

Wickenden and Shaw note that ‘although this section indicates that the Goodrich consists chiefly of sandstone, exposures elsewhere in the area point to the presence of several fairly thick shale bands”, for example ‘‘on Hul- cross Creek, 2 and 4 miles above the forks of Alvin Creek, and on Walton Creek, 4 miles above the forks... on Walton Creek they are about 60 feet thick and occupy a position approximately 300 feet above the base of the formation”.

The contact of the Goodrich with the underlying Hasler formation is fairly sharp on Hulcross and Walton Creeks, marked by ‘‘a change from dark grey shale below to hard, massive sandstone above; at the remaining localities the contact is transitional through several beds of alternating sandstone and shale’’.

Wickenden and Shaw found it difficult to measure this formation because in few sections are both the upper and lower contacts exposed. Such a section, however, was found on Bowlder Creek, where a thickness of 550 to 600 feet was measured.

Fossils are abundant in the Goodrich formation at some localities in Pine River Valley. All are marine. Shells of the genus Oxytoma are common, and indeed the Goodrich could be called the Ozytoma sandstone. A variety of Posidonomya nahwisi isa very characteristic fossil, and has been collected on the north side of Pine River Valley 2 miles west of Bowlder Creek; on the west side of Hulcross Creek Valley, north of the west branch; from a shaly member 1 mile above Alvin’s cabin on Huleross Creek; in a gully west of Johnsen Creek; and elsewhere. Ozxytoma pinan a and Pleuromya kissoumt were collected on a mountain east of the east branch of Commotion Creek. Tancredia stelcki is from the north side of Pine River Valley, 2 miles west of Bowlder Creek. Pleuromya wickendeni and Lucina? goodrichensis, collected by C. R. Stelek, are from the south valley wall east of Young Creek.

The Goodrich formation does not outcrop on the banks of Peace River near the canyon; it has evidently been removed by erosion, even from the synclines. It does, however, outcrop on high uplands south of the canyon and in the valley of Moberly River. Beach and Spivak (1944) state that the “Goodrich formation is exposed on the south side of Peace River, on Tworidge Mountain, and near Pete Lake in the Moberly River region. Its thickness is estimated to be 550 feet’’, and it comprises ‘‘a series of interstratified, buff to light grey, medium- to coarse-grained sandstones, and black, sandy shales. On Burnt Trail Creek, the lowermost 50 feet of the Goodrich includes 20 feet of coarse conglomerate containing varie- gated chert pebbles + inch to 14 inches in diameter. Underlying beds are of medium- to coarse-grained, grey, crossbedded sandstone, with some clay ironstone bands’’.

Beach and Spivak measured a section near the base of the formation on a creek north of Tworidge Mountain; in descending order it is as follows:

Thickness

z Feet

Sandstone, fine-grained, greenish [Niet oe couoberongedonooee 122 Sandstone, thin-bedded, grey; thin shale beds................. 21 Shale, black, fissile; ironstone concretionary bands............. 42 Sandstone, grey, fine-grained, partly micaceous................ 41 Sandstone, grey-green; some concretionary bands.............. 29 Sandstone, quartzitic, grey-green............................ 11 Shale, black, sandy; carbonaceous fragments; fossils............ 6 Rotalithickness sere erent ee eee eee 272