Extended Data Fig. 2: Modelled melt compositions as in Fig. 3 of the main text, showing the effect of switching from fractional to batch crystallisation at different points in crystallisation history. | Nature Geoscience

Extended Data Fig. 2: Modelled melt compositions as in Fig. 3 of the main text, showing the effect of switching from fractional to batch crystallisation at different points in crystallisation history.

From: A mid-crustal tipping point between silica-undersaturated and silica-oversaturated magmas

Extended Data Fig. 2: Modelled melt compositions as in Fig. 3 of the main text, showing the effect of switching from fractional to batch crystallisation at different points in crystallisation history.

a) Fractional crystallisation to 99 vol.% (no batch crystallisation step). Crosses mark first 50, 75 and 90% of crystallization, with symbols marking state of silica saturation at 95% crystallisation. b) Fractional crystallisation to 90 vol.% (example melt paths as dotted lines), batch crystallisation to complete crystallisation (solid lines). Whole-rock geochemistry12,14,28 for BLIC shown in coloured symbols following Fig. 1: orange shades for eastern lobe of Nechalacho Layered Suite (circle), Thor Lake syenite (diamond), Grace Lake granite (cross); blue shades for western lobe of Hearne Channel/Mad Lake granite (upwards triangle), Whiteman Lake syenite (pentagon) and Caribou Lake gabbo (inverted triangle). Mineral abbreviations are clinopyroxene (cpx), feldspar (fsp), forsterite (Fo), anorthite (an), albite (ab), diopside (di), hedenbergite (hd), aegirine (aeg), olivine (ol).

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