Osmium evidence for synchronicity between a rise in atmospheric oxygen and Palaeoproterozoic deglaciation

Abstract

Early Palaeoproterozoic (2.5-2.0 billion years ago) was a critical phase in Earth's history, characterized by multiple severe glaciations and a rise in atmospheric o 2 (the Great oxidation Event). Although glaciations occurred at the time of o 2 increase, the relationship between climatic and atmospheric transitions remains poorly understood. Here we report high concentrations of the redox-sensitive element os with high initial 187 os/ 188 os values in a sandstone-siltstone interval that spans the transition from glacial diamictite to overlying carbonate in the Huronian supergroup, Canada. Together with the results of Re, mo and s analyses of the sediments, we suggest that immediately after the second Palaeoproterozoic glaciation, atmospheric o 2 levels became sufficiently high to deliver radiogenic continental os to shallow-marine environments, indicating the synchronicity of an episode of increasing o 2 and deglaciation. This result supports the hypothesis that climatic recovery from the glaciations acted to accelerate the Great oxidation Event.

Transient episodes of mild environmental oxygenation and oxidative continental weathering during the late Archean

“…Previously, the oldest known example of radiogenic Os delivery to seawater was captured by sedimentary rocks of the Huronian Supergroup, deposited in the aftermath of a widespread Paleoproterozoic glaciation at ca. 2.3 Ga ( 34 ). All other black shales between 2.7 and 2.0 Ga ( n = 5) yield initial 187 Os/ 188 Os values from Re-Os isochron regressions that are indistinguishable from the mantle/extraterrestrial value ( 1 , 35 – 38 ).…”

“…Early Paleoproterozoic (ca. 2.3 Ga) sandstones and siltstones have initial 187 Os/ 188 Os as high as 1.1 ( 34 ), which may represent an approximate upper limit for the 187 Os/ 188 Os of the eroding upper continental crust at 2.5 Ga. The Os isotope mass balance equation for seawater can be represented by where the f terms represent the relative fraction of Os input to seawater and f continental + f mantle/extraterrestrial = 1.…”

Searching for the Great Oxidation Event in North America: A Reappraisal of the Huronian Supergroup by SIMS Sulfur Four-Isotope Analysis

“…Age constraints were measured from Nipissing diabase (Corfu and Andrews, 1986) and Copper Cliff Formation (Krogh et al, 1984;Ketchum et al, 2013). Geochemical data include sulfur isotopes (Hattori et al, 1983;Papineau et al, 2007), CIA (Nesbitt and Young, 1982), high initial 187 Os/ 188 Os and redox-sensitive elements (e.g., Mo, Re) (Sekine et al, 2011a), and MnO-Fe 2 O 3 enrichment right after the Gowganda glaciation (Sekine et al, 2011b). Note that the previously proposed MIF-MDF transition (Papineau et al, 2007) has been reevaluated in this study.…”

“…1 and 2) is one of the most-studied Paleoproterozoic sedimentary records in the world and thus bears the potential to capture the GOE. Intensive studies have been conducted on the sedimentology (e.g., Wood, 1973;Young, 1991;Hill et al, 2016), geochronology (e.g., Krogh et al, 1984;Corfu and Andrews, 1986;Ketchum et al, 2013;Rasmussen et al, 2013), paleomagnetism (e.g., Williams and Schmidt, 1997), biomarkers (e.g., Dutkiewicz et al, 2006), and chemostratigraphy (e.g., Nesbitt and Young, 1982;Wing et al, 2002Wing et al, , 2004Bekker and Kaufman, 2007;Papineau et al, 2007;Sekine et al, 2011aSekine et al, , 2011bGoto et al, 2013) of the Huronian Supergroup.…”

Osmium Isotopic Evidence for Eccentricity‐Paced Increases in Continental Weathering During the Latest Hauterivian, Early Cretaceous

“…Besides, Selby and Creaser (2003) proposed that CrO 3 -H 2 SO 4 is a more appropriate method to extract the hydrogenous fraction of Re-Os information than aqua regia because CrO 3 -H 2 SO 4 weakly attacked silicate minerals, such as quartz and feldspar. However, the Re-Os information extracted with these two methods is almost identical (Matsumoto et al, 2020;Sekine et al, 2011;Selby & Creaser, 2003). Accordingly, Matsumoto et al ( 2020) applied both extraction methods for the Re-Os analysis Cretaceous sedimentary rock samples collected from the Umbria-Marche Basin and the reconstructed 187 Os/ 188 Os values of both high Os-black shale and low-Os carbonate samples are almost identical.…”