Evolving mantle convection from bottom up to top down

Mitchell, Ross N.; Brown, Michael; Gernon, Thomas; Spencer, Christopher J.

doi:10.1016/j.xinn.2022.100309

Cited by 1 publication

(2 citation statements)

References 3 publications

(8 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sudden outburst of biogenic carbonate platforms globally around 2.5 Ga (Fig. 10) may thus share a common triggering mechanism, showing a link of deep Earth processes such as a transition from bottom-up to top-down mantle convection 69 and the oxygenation of the atmosphere near the Archaean-Proterozoic boundary 3,[66][67][68] . As protocontinents were generally stabilized by intraoceanic arc amalgamation around the Archaean-Proterozoic boundary 2 , biogenic carbonate platforms were built as a consequence.…”

Section: Discussionmentioning

confidence: 99%

“…As protocontinents were generally stabilized by intraoceanic arc amalgamation around the Archaean-Proterozoic boundary 2 , biogenic carbonate platforms were built as a consequence. The sudden rise of oxygen from these oases eventually led to global change and the later GOE event started about 2.45 Gyr, making Earth a more habitable planet [66][67][68][69] .…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Passive margins in accreting Archaean archipelagos signal continental stability promoting early atmospheric oxygen rise

et al. 2022

View full text Add to dashboard Cite

Significant changes in tectonic style and climate occurred from the late Archaean to early Proterozoic when continental growth and emergence provided opportunities for photosynthetic life to proliferate by the initiation of the Great Oxidation Event (GOE). In this study, we report a Neoarchaean passive-margin-type sequence (2560–2500 million years ago) from the Precambrian basement of China that formed in an accretionary orogen. Tectonostratigraphic and detrital zircon analysis reveal that thermal subsidence on the backside of a recently amalgamated oceanic archipelago created a quiet, shallow water environment, marked by deposition of carbonates, shales, and shallow water sediments, likely hosts to early photosynthetic microbes. Distinct from the traditional understanding of passive margins generated by continental rifting, post-collisional subsidence of archipelago margins represents a novel stable niche, signalling initial continental maturity and foreshadowing great changes at the Archaean-Proterozoic boundary.

show abstract