Testing the importance of sagduction: insights from the Lewisian Gneiss Complex of northwest Scotland

Earth's Earliest Phaneritic Ultramafic Rocks: Mantle Slices or Crustal Cumulates?

“…Most researchers interpret that East Pilbara Terrane represents a Paleoarchean terrane formed via regional hot stagnant‐lid tectonics featuring partial crustal convection (e.g., Collins et al., 1998; François et al., 2014; Johnson et al., 2017; Moore & Webb, 2013; Van Kranendonk, 2010; Van Kranendonk et al., 2007; Wiemer et al., 2018), driven by episodic mantle plume events and gravitational instability (e.g., Fischer & Gerya, 2016; cf. Miocevich et al., 2022), although a plate tectonic origin has also been proposed (e.g., Kusky et al., 2021). The proposed model involving partial convective overturn cooling (Collins et al., 1998) predicts that the East Pilbara Terrane experienced episodic supracrustal volcanism and tonalite petrogenesis followed by quiescence during ∼10 to ∼100 million years cycles of mantle plume activities.…”

Paleoarchean metamorphism in the Acasta Gneiss Complex: Constraints from phase equilibrium modelling and in situ garnet Lu–Hf geochronology

“…Deciphering the mechanisms of formation of ancient continental crust and its evolution to form stable cratons are keys to understanding geodynamic processes operating in the late Hadean and Archean (e.g., Bédard, 2018;Brown et al, 2020;Hastie et al, 2016;Johnson et al, 2014Johnson et al, , 2017Korenaga, 2021;Miocevich et al, 2022;Moyen, 2011;Palin, White, Green, Diener, et al, 2016). However, direct constraints on Earth's earliest history are sparse and commonly derived from rocks that have undergone multistage reworking and recrystallization during subsequent tectono-thermal events (Moyen & Martin, 2012;Wiemer et al, 2018).…”