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Figure 8.

Summary cartoon showing the three stages of craton creation and stabilization, with the times at which these stages operated in the Wyoming craton (WC). (A) Initial stage in which thickened mafic crust, possibly formed over a mantle plume, partially melts at depth to form small volumes of zircon-bearing felsic melt. (B) Middle stage in which a trondhjemite-tonalite-granodiorite (TTG) crust forms from both mantle and crustal sources. Subduction is one potential mechanism for transporting mafic crust to depth for partial melting. (C) Final stage of Archean crustal evolution in which continental freeboard has increased and evidence of magmatic arcs, continent-continent collisions, and terrane accretion is abundant.

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