Thousands of cubic kilometres of calc-alkaline intermediate to silicic magma erupted in eastern Nevada at ≈35 Ma. On the basis of petrologic models, crustal contribution to magmatism is slightly greater than basaltic input. The volume of crystals generated during differentiation is roughly twice that of erupted magma, implying that intrusive complements are enriched in accumulated crystals. The amount of basalt needed to drive the system thermally can be derived from the volume of crust that is heated and assimilated, and is about twice the volume of basalt needed materially.

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