Summary: | In the southern Selwyn Range, Hadrynian Miette Group strata form a thick conformable sequence. A distinctive carbonate unit in the middle Miette Group is assigned to the Old Fort Point Formation. Facies variations in the middle Miette Group, from grit dominated in the east to pelite dominated in the west, delineate a channel or fan lobe margin. === Structures in the southern Selwyn Range developed during three main phases of deformation. The Fraser River Antiform, the dominant structure, formed during D$ sb2$. The Selwyn Range Fault cross-cut the earlier Fraser River Antiform during early D$ sb3$. The Fraser River Antiform tightened during late D$ sb3$, when the Selwyn Range Fault was reactivated, forming a 100m thick shear zone. The Chatter Creek Fault (D$ sb3$ or latter) has compressional and dextral motion, both with minor displacement. === Metamorphism was initiated during D$ sb2$ and peaked during D$ sb3$.
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