Abstract

Conclusions are based on some 36 sections studied by members of the GSC Operation Porcupine in 1962 in an area of about 80,000 square miles north of latitude 65° and west of longitude 132°.

Formation names used comprise the Michelle, Gossage, Prongs Creek, Cranswick, Ogilvie, Hume, Hare Indian, Canol, an unnamed shale, and Imperial—of which the first five are new.

The Michelle Formation of Emsian to Eifelian age consists of limestone, dolomite and shale developed in the Hart-Ogilvie Rivers area. The Gossage Formation applies to banded dolomites and limestones roughly coeval with the Bear Rock evaporites and breccia. The Prongs Creek Formation applies to shale, argillaceous limestone and chert developed in the Richardson Mountain uplift, and ranges in age from Lower to Middle Devonian and possibly younger. The Cranswick Formation of Eifelian age consists of limestone and calcareous shale developed in the Snake River area. The Ogilvie Formation of Eifelian to Givetian age consists of resistant grey-weathering carbonates. The Hume Formation of Eifelian to Givetian age pinches out westward near Snake River. An unusually thick sequence of green calcareous shale in the Snake River area is referred to the Hare Indian Formation, but is largely older than this formation of the type area. The Canol Shale of Frasnian age occurs mainly in the eastern part of the area. The unnamed shale refers to an interval of poorly exposed shales ranging in age from Middle to Upper Devonian present mainly in the Ogilvie Mountains. The Imperial Formation of Frasnian to Famennian age consists of clastic rocks up to 6,000 feet thick.