Palaeoproterozoic supercontinents and global evolution: correlations from core to atmosphere

Abstract

The Palaeoproterozoic era was a time of profound change in Earth evolution and represented perhaps the first supercontinent cycle, from the amalgamation and dispersal of a possible Neoarchaean supercontinent to the formation of the 1.9-1.8 Ga supercontinent Nuna. This supercontinent cycle, although currently lacking in palaeogeographic detail, can in principle provide a contextual framework to investigate the relationships between deep-Earth and surface processes. In this article, we graphically summarize secular evolution from the Earth's core to its atmosphere, from the Neoarchaean to the Mesoproterozoic eras (specifically 3.0-1.2 Ga), to reveal intriguing temporal relationships across the various 'spheres' of the Earth system. At the broadest level our compilation confirms an important deep-Earth event at c. 2.7 Ga that is manifested in an abrupt increase in geodynamo palaeointensity, a peak in the global record of large igneous provinces, and a broad maximum in several mantle-depletion proxies. Temporal coincidence with juvenile continental crust production and orogenic gold, massive-sulphide and porphyry copper deposits, indicate enhanced mantle convection linked to a series of mantle plumes and/or slab avalanches. The subsequent stabilization of cratonic lithosphere, the possible development of Earth's first supercontinent and the emergence of the continents led to a changing surface environment in which voluminous banded iron-formations could accumulate on the continental margins and photosynthetic life could flourish. This in turn led to irreversible atmospheric oxidation at 2.4-2.3 Ga, extreme events in global carbon cycling, and the possible dissipation of a former methane greenhouse atmosphere that resulted in extensive Palaeoproterozoic ice ages. Following the great oxidation event, shallow marine sulphate levels rose, sediment-hosted and iron-oxide-rich metal deposits became abundant, and the transition to sulphide-stratified oceans provided the environment for early eukaryotic evolution. Recent advances in the geochronology of the global stratigraphic record have made these inferences possible. Frontiers for future research include more refined modelling of Earth's thermal and geodynamic evolution, palaeomagnetic studies of geodynamo intensity and continental motions, further geochronology and tectonic syntheses at regional levels, development of new isotopic systems to constrain geochemical cycles, and continued innovation in the search for records of early life in relation to changing palaeoenvironments.

Antarctica and supercontinent evolution: historical perspectives, recent advances and unresolved issues

“…Attention switches to the Mawson Continent for reconstructions of Nuna -which is believed to have assembled by the collision of multiple continental blocks along a series of Palaeoproterozoic orogens, with the final stages of assembly at 1.9 -1.8 Ga (Zhao et al 2004;Reddy & Evans 2009;Evans & Mitchell 2011). Important questions in Antarctica include whether the Mawson Continent extends as far as the Miller and Shackleton ranges, and, if so, whether there is a continuous 1.7 Ga orogen between these outcrops and the Gawler Craton of South Australia (Payne et al 2009).…”

Paleomagnetism of the Amazonian Craton and its role in paleocontinents

“…This supercontinent has received different names: NENA (Gower et al 1990), NUNA (Hoffman 1997), Columbia (Rogers & Santosh 2002), or Paleopangea (Piper 2010). Reddy & Evans (2009) advocate the name NUNA because it is older than the name Columbia. However, Meert (2012) argues that the NUNA paleocontinent defined by Hoffman (1997) differs little from the NENA proposed by Gower et al (1990).…”

Palaeoproterozoic of India: an introduction

“…A relatively rapid change in the Earth's surface processes has been anticipated across the ArchaeanPalaeoproterozoic boundary as a consequence of changes in the crust -mantle system and tectonic regime (Condie 1989(Condie , 1997Eriksson et al 2004;Reddy & Evans 2009). The Palaeoproterozoic era (2500-1600 Ma : Plumb 1991) represented perhaps the first supercontinent cycle, from the amalgamation and dispersal of a Neoarchaean supercontinent to the formation of the 1.9-1.8 Ga supercontinent Nuna (Reddy & Evans 2009), and encompasses one or more global tectonic event that coincides with fundamental changes in the integrated system of core, mantle, lithosphere, hydrosphere, atmosphere and biosphere (i.e.…”

“…The Palaeoproterozoic era (2500-1600 Ma : Plumb 1991) represented perhaps the first supercontinent cycle, from the amalgamation and dispersal of a Neoarchaean supercontinent to the formation of the 1.9-1.8 Ga supercontinent Nuna (Reddy & Evans 2009), and encompasses one or more global tectonic event that coincides with fundamental changes in the integrated system of core, mantle, lithosphere, hydrosphere, atmosphere and biosphere (i.e. an integrated Earth System).…”

“…an integrated Earth System). An integration of seemingly disparate geoscience disciplines is therefore an essential prerequisite to understand these changes (Reddy & Evans 2009); and that was the aim of the UNESCO-IGCP 509 project (2005-2009) on Palaeoproterozoic Supercontinents and Global Evolution.…”