Petrogenetic modeling reveals variable sediment recycling generated chemical diversity in late Archean sanukitoids, indicating modern-style plate subduction and continental weathering.
Key Points
Investigate the petrogenetic origins and geodynamic drivers behind the chemical diversity observed in late Neoarchean sanukitoid suites.
Analyzed whole-rock major and trace element geochemistry alongside zircon U–Pb and Lu–Hf isotopic compositions of late Neoarchean (~2560–2491 Ma) gneisses.
Performed thermodynamic and trace element modeling to constrain mantle melt sources, recycling percentages, and melting pressure-temperature conditions.
Dioritic gneisses were modeled from a mixed mantle source with 6% sediment-derived melts at 1.4–1.9 GPa and 1030–1060°C.
Monzodioritic and quartz monzodioritic gneisses required higher sediment melt inputs of 9% (at 2.0–2.1 GPa, 980–1050°C) and 11% (at 2.4–2.8 GPa, 1050–1070°C), respectively.
Global compilations confirm that this systematic chemical variation emerged during the Neoarchean, reflecting hot subduction zones coupled with continental emergence and weathering.