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Not AvailableThe ancient history of the Earth is marked by pivotal times recorded in Precambrian terrains, providing crucial insight into the evolution of the crust-mantle system and the geodynamic processes operating in the evolving Earth. This research focuses on the Zimbabwe craton, an important ancient terrain where fundamental concepts of Archean tectonics were first defined and that remains largely uncharacterized by high-precision isotope studies. We integrate in-situ LA-ICPMS zircon U-Pb ages and Hf isotope compositions of magmatic samples and river sands to investigate the Paleo- and Meso-Neoarchean (∼3.6–3.3 Ga and ∼2.9–2.7 Ga) crustal evolution of the craton. Zircon U-Pb data from gneiss complexes and granites within the central part of the craton, which encompasses the Sebakwe proto-craton that experienced tectonic stability temporarily between 3.3 and 3.0 Ga ago, define a main magmatic event at 3.6–3.5 Ga and minor components at ∼3.3 Ga, ∼2.9 Ga, and 2.7 Ga. Outside of the central part of the craton within the Odzi-Mutare area the magmatic record is dominated by zircon U-Pb ages between 2.9 and 2.8 Ga. A similar age distribution is recorded by detrital zircon from modern sediments with age clusters in the Paleoarchean at 3.6–3.5 Ga and 3.4–3.3 Ga, with the latter being more prominent, and in the Meso-Neoarchean at 2.9–2.8 Ga and 2.6 Ga. The Paleoarchean magmatic components yield Hf isotope compositions within 4 epsilon units of CHUR (ƐHf(3.6-3.3Ga) + 2 to –4), similar to the isotope compositions of detrital zircons (ƐHf(3.6-3.3Ga) + 2 to –6). Meso-Neoarchean magmatic components yield Hf isotope compositions with ƐHf(i) between CHUR and +2 at ∼2.9–2.8 Ga, while detrital zircons range from ƐHf(i) + 4 to –9 at ∼2.9–2.6 Ga. Data from the Zimbabwe craton indicate crust formation in the Paleoarchean (3.6–3.3 Ga) that involved juvenile magma additions and a possible derivation from a ∼3.8 Ga chondritic source and craton-wide crust forming episodes between ∼2.9 and 2.6 Ga that involved crustal reworking in various degrees along with new additions of juvenile material. The Hf isotope record of the Zimbabwe craton aligns with the global isotope record—with chondritic to sub-chondritic Hf isotope compositions at ∼3.7–3.6 Ga, the appearance of juvenile additions after ∼3.5 Ga, and mixing trends after ∼3.0 Ga—supporting formation of a long-lived depleted mantle reservoir after ∼3.6 Ga. 

Plate tectonics is a fundamental factor in the sustained habitability of Earth, but its time of onset is unknown, with ages ranging from the Hadaean to Proterozoic eons1–3. Plate motion is a key diagnostic to distinguish between plate and stagnant-lid tectonics, but palaeomagnetic tests have been thwarted because the planet’s oldest extant rocks have been metamorphosed and/or deformed4. Herein, we report palaeointensity data from Hadaean-age to Mesoarchaean-age single detrital zircons bearing primary magnetite inclusions from the Barberton Greenstone Belt of South Africa5. These reveal a pattern of palaeointensities from the Eoarchaean (about 3.9 billion years ago (Ga)) to Mesoarchaean (about 3.3 Ga) eras that is nearly identical to that defined by primary magnetizations from the Jack Hills (JH; Western Australia)6,7, further demonstrating the recording fidelity of select detrital zircons. Moreover, palaeofield values are nearly constant between about 3.9 Ga and about 3.4 Ga. This indicates unvarying latitudes, an observation distinct from plate tectonics of the past 600 million years (Myr) but predicted by stagnant-lid convection. If life originated by the Eoarchaean8, and persisted to the occurrence of stromatolites half a billion years later9, it did so when Earth was in a stagnant-lid regime, without plate-tectonics-driven geochemical cycling.