Age and correlation These rocks were mapped by Campbell (1978) as Upper Triassic or Lower Jurassic (unit TJa) of the Quesnel River Group and are accepted as such here. Economic geology Within the confines of the detailed mapping, Quesnel Terrane hosts no economic minerals in lode deposits. Placer gold is found near Wingdam in gravels overlying the black phyllite unit, but there appears to be no rela- tionship to bedrock, because gravels overlying Snowshoe Group rocks also contain some gold in the vicinity. Both the black phyllite and Triassic volcaniclastic units host concentrations of copper, gold and lead to the southwest of the area along a trend from Quesnel River southeast to Eureka Mountain (Saleken and Simpson, 1984). The minerals occupy quartz veins and country rock in seemingly stratabound replacements or as dissemina- tions in alkalic plutonic rocks (ibid). Structure and metamorphism The structure and metamorphism were insufficiently stud- ied because of the limited mapping of the Quesnel Terrane. Ductile to semiductile folds and cleavage are overprinted by local shear and crenulations. The cleavage is southwest dipping, penetrative, com- monly parallel to bedding and the axial planes of open, tight and isoclinal folds. It is defined by pressure solu- tion selvages and accumulations of parallel, finely crystal- line white mica. Locally it defines the shear foliation in phyllonite. The fold style varies with lithology; it is paral- lel in pelite and concentric in quartzite or siltite. Folds trend west-northwest and verge north-northeast. Stretched clasts in the Wingdam conglomerate are elon- gate in the same direction as the trend of the fold axes. Shear, as recorded by zones of phyllonite, appears as bands some | to 15 m thick and parallels the contact with the Crooked amphibolite. The shear obliterates folds and is itself affected by crenulations. Crenulations trend at 120?and have axial surfaces that dip to the southwest. They may be related to region- al folds such as those marked by the Crooked amphibo- lite to the southeast. ACKNOWLEDGEMENTS Part of the work was done as a doctoral thesis at the Uni- versity of Calgary under the supervision of P.S. Simony and during tenure of a post-doctoral fellowship (NSERC). R.B. Campbell inspired the project and with J.A. Roddick suggested improvements to the manuscript. 80 REFERENCES (Includes references cited in Appendix B) Alldrick, D. J. 1983: The Mosquito Creek Mine, Cariboo gold belt (93H/4); in Geo- logical Fieldwork 1982, British Columbia Ministry of Energy, Mines and Petroleum Resources, Paper 1983-1, p. 99-112. Andrew, A., Godwin, C. I., and Sinclair, A. 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