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Assessing Inheritance Of Zircon And Monazite In Granitic Rocks From The Monashee Complex, Canadian Cordillera, James Crowley, R. L. Brown, F. Gervais, H. D. Gibson

Geosciences Faculty Publications and Presentations

Zircon and monazite from granitic sheets and dikes in the Monashee complex, Canadian Cordillera, were investigated to determine whether igneous crystallization occurred at 1.9 Ga or 50 Ma with 1.9 Ga inherited zircon and monazite. Four of the five samples are weakly deformed to undeformed, despite occurring in a gneiss dome at the structurally deepest exposed level of the orogen that elsewhere was strongly deformed and partly melted at 50 Ma. Based on U-(Th)-Pb dates from zircon and monazite, field relationships, and mineral composition and zoning, we conclude that the granitic rocks crystallized at 1.9 Ga and were metamorphosed at …