Precambrian supercontinents and supercycles - an overview

Abstract There is ample evidence that supercontinent cycles on Earth have been operating since the Late Paleoproterozoic. Evidence for the supercontinent cyclicity arises from multidisciplinary observations from geology, geochronology, geophysics (e.g., paleomagnetism, seismology, heat flow), isotope geology, and geochemistry. This overview summarizes current views of Precambrian supercontinent episodicity or cyclicity. In addition, paleogeographic reconstructions based on global key paleomagnetic poles and kinematic models of Paleo-Mesoproterozoic Nuna supercycle, Meso-Neoproterozoic Rodinia supercycle, and the Phanerozoic Gondwana/Pangea supercycle are explored. The lifecycle of supercontinents is tested by geological, geophysical, and geochemical data coupled with secular evolution trends of Earth. Results suggest that (1) supercontinent cyclicity has a characteristic (quasi-) period of ~700–500 million years, supported by planetary secular evolutionary trends, but other periods are also present; (2) supercontinents Nuna, Rodinia, and Gondwana/Pangea have different configurations and secular evolutionary trends possibly due to different tectonic styles of assembly; (3) globally averaged plate velocity during the Precambrian reveals a wave-like pattern with peaks and lows corresponding with features in several secular evolution indices including the distribution of U−Pb ages, passive margins, metamorphic events, tectonic proxies, and magmatic activity; (4) the data suggest three tectonomagmatic lulls during the Proterozoic, but the proposed Mesoproterozoic quiescent period, coined as “boring billion” years of Earth history (1.8–0.8 Ga) appears to be seen mainly by atmospheric and biospheric data rather than tectonomagmatic activity; and (5) tectonic processes driving supercontinent cyclicity are interactive, with feedbacks from all six spheres of the Earth—the geosphere, cryosphere, hydrosphere, biosphere, atmosphere, and magnetosphere.