Supplemental Material: Deep-time thermal history of the Great Unconformity in the Grand Canyon, USA: Combined zircon (U-Th)/He and K-feldspar 40Ar/39Ar thermochronometers

Additional modeling methodology and results. In particular the Supplemental Material contains comparisons of measured versus modeled (U-Th)/He zircon ages modeled in both QTQt and HeFTy, detailed Ar/Ar MDD modeling methods, Domain 2 QTQt models, and an assessment of grain selection for HeFTy models.