Mojtaba Fakhraee

TL;DR: In this paper, the authors used mass balance and diagenetic reaction-transport models to reconstruct the sulfate concentrations in Proterozoic seawater, and found that sulfate levels remained below 400 µm and were possibly as low as 100 µm, throughout much of the Proteozoic.

TL;DR: Assessment of chemical hazard to the surrounding aquatic environment should not be carried out through traditional approaches and anthropogenic portion of the metals was determined through one-step chemical sequential extraction and lithogenous portion substituted for the mean crust and shale levels in the new pollution index (RIAquatic).

TL;DR: In this article, the authors explore an alternative model where Mn-carbonates form in redox-stratified water columns linked to calcium carbonate dissolution, and demonstrate that sedimentary Mn enrichments may develop from primary carbonate phases, and can occur in environments with dissolved oxygen concentrations 200 μM.

TL;DR: In this paper, the authors used a mechanistic model of the biological carbon pump to revisit the factors controlling the transfer efficiency of carbon from surface waters to the ocean interior and marine sediments.

TL;DR: A reaction-transport model is developed to analyze the preservation patterns of sulfur isotopes in Archean sedimentary pyrites, one of the most robust and widely distributed proxies for early Earth biogeochemistry, and reveals that micromolar levels of O2 in seawater enhance the preservation of large MIF-S signals, whereas concomitant ingrowth of sulfate expands the ranges in pyrite δ34S.