Trace elements at the intersection of marine biological and geochemical evolution

LJ Robbins, SV Lalonde, NJ Planavsky, CA Partin… - Earth-Science …, 2016 - Elsevier
Life requires a wide variety of bioessential trace elements to act as structural components
and reactive centers in metalloenzymes. These requirements differ between organisms and …

Bioactive trace metals and their isotopes as paleoproductivity proxies: An assessment using GEOTRACES‐era data

TJ Horner, SH Little, TM Conway… - Global …, 2021 - Wiley Online Library
Phytoplankton productivity and export sequester climatically significant quantities of
atmospheric carbon dioxide as particulate organic carbon through a suite of processes …

Low Mid-Proterozoic atmospheric oxygen levels and the delayed rise of animals

NJ Planavsky, CT Reinhard, X Wang, D Thomson… - science, 2014 - science.org
The oxygenation of Earth's surface fundamentally altered global biogeochemical cycles and
ultimately paved the way for the rise of metazoans at the end of the Proterozoic. However …

A shale-hosted Cr isotope record of low atmospheric oxygen during the Proterozoic

DB Cole, CT Reinhard, X Wang, B Gueguen… - …, 2016 - pubs.geoscienceworld.org
The emergence and expansion of animal life on Earth represents a dramatic shift in the
structure and complexity of the biosphere. A lack of firm constraints on surface oxygen levels …

[PDF][PDF] Controls on trace metal authigenic enrichment in reducing sediments: insights from modern oxygen-deficient settings

SH Little, D Vance, TW Lyons… - American Journal of …, 2015 - ajsonline.org
Any effort to reconstruct Earth history using variations in authigenic enrichments of redox-
sensitive and biogeochemically important trace metals must rest on a fundamental …

A new estimate of detrital redox-sensitive metal concentrations and variability in fluxes to marine sediments

DB Cole, S Zhang, NJ Planavsky - Geochimica et Cosmochimica Acta, 2017 - Elsevier
The enrichment and depletion of redox sensitive trace metals in marine sediments have
been used extensively as paleoredox proxies. The trace metals in shale are comprised of …

Correlated molybdenum and uranium isotope signatures in modern anoxic sediments: Implications for their use as paleo-redox proxy

A Brüske, S Weyer, MY Zhao, NJ Planavsky… - … et Cosmochimica Acta, 2020 - Elsevier
Redox-sensitive trace metals and their isotopes have emerged as important tools that are
used to reconstruct the redox-evolution of the ocean-atmosphere system. However …

Global variability of chromium isotopes in seawater demonstrated by Pacific, Atlantic, and Arctic Ocean samples

K Scheiderich, M Amini, C Holmden… - Earth and Planetary …, 2015 - Elsevier
Seawater chromium (Cr) isotope and concentration data are presented from multiple sites in
the Arctic Ocean, and three locations in the Atlantic and Pacific Oceans. A 2400-m profile …

Response of the Cr isotope proxy to Cretaceous Ocean Anoxic Event 2 in a pelagic carbonate succession from the Western Interior Seaway

C Holmden, AD Jacobson, BB Sageman… - … et Cosmochimica Acta, 2016 - Elsevier
Chromium offers a redox sensitive isotopic proxy with potential for tracing past oxygen levels
in the oceans. We explore this potential in a pelagic succession of marine carbonate …

Chromium isotope geochemistry

L Qin, X Wang - Reviews in Mineralogy and …, 2017 - pubs.geoscienceworld.org
Chromium consists of four stable isotopes (50 Cr, 52 Cr, 53 Cr and 54 Cr) with natural
abundances of 4.35%, 83.79%, 9.50% and 2.36%, respectively (Rossman and Taylor 1998) …