Mark Barley

TL;DR: A decline in the molar nickel to iron ratio recorded in banded iron formations about 27 Gyr ago was attributed to a reduced flux of nickel to the oceans, a consequence of cooling upper-mantle temperatures and decreased eruption of nickel-rich ultramafic rocks at the time as mentioned in this paper.

TL;DR: Observations are consistent with the corollary that subaerial volcanism only became widespread after a major tectonic episode of continental stabilization at the beginning of the Proterozoic, and propose that the rise of atmospheric oxygen occurred because the predominant sink for oxygen in the Archaean era—enhanced submarine volcanism—was abruptly and permanently diminished.

TL;DR: In this article, a decline in the molar nickel to iron ratio recorded in banded iron formations about 2.7 Gyr ago was attributed to a reduced flux of nickel to the oceans, a consequence of cooling upper-mantle temperatures and decreased eruption of nickel-rich ultramafic rocks at the time.

TL;DR: An independent and complementary record of marine Cr supply is provided, in the form of Cr concentrations and authigenic enrichment in iron-rich sedimentary rocks, to add to amassing evidence that the Archaean-Palaeoproterozoic boundary was marked by a substantial shift in terrestrial geochemistry and biology.

TL;DR: In this article, the discovery of an angular unconformity (an ancient erosion surface) beneath rocks of the 3.46-Gyr Warrawoona Group in the Pilbara craton of Australia, currently the oldest known well-preserved greenstone succession was reported.