Mercury in some arc crustal rocks and mantle peridotites and relevance to the moderately volatile element budget of the Earth

Canil, Dante; Crockford, Peter W.; Rossin, Ricardo; Telmer, Kevin

doi:10.1016/j.chemgeo.2014.12.029

Cited by 44 publications

(16 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Geogenic Hg from crustal rocks in U.S. typically exhibits more positive δ 202 Hg (~ −0.6 ± 0.5‰, 1SD) [ Smith et al ., ] and negligible MIF [ Blum et al ., ], and both are in contrast with the observed more negative δ 202 Hg (typically < −1‰) and significant MIF in our mineral soil samples. Mercury concentration in crustal rocks is still poorly defined, but a recent study on arc crustal rocks reported much lower Hg concentration (2.9 ± 2.6 ppb) [ Canil et al ., ] than most of our mineral soil samples. In addition, previous studies on Hg sources in soils using geochemical ratios also show that the dominant source of Hg in upper soils is from exogenic (i.e., atmospheric) inputs rather than from geogenic sources [ Grimaldi et al ., ; Fiorentino et al ., ; Peña‐Rodríguez et al ., ].…”

Section: Resultsmentioning

confidence: 90%

Mercury isotope compositions across North American forests

Zheng

Obrist

Weis

et al. 2016

Global Biogeochemical Cycles

187

195

View full text Add to dashboard Cite

Forest biomass and soils represent some of the largest reservoirs of actively cycling mercury (Hg) on Earth, but many uncertainties exist regarding the source and fate of Hg in forest ecosystems. We systematically characterized stable isotope compositions of Hg in foliage, litter, and mineral soil horizons across 10 forest sites in the contiguous United States. The mass‐independent isotope signatures in all forest depth profiles are more consistent with those of atmospheric Hg(0) than those of atmospheric Hg(II), indicating that atmospheric Hg(0) is the larger source of Hg to forest ecosystems. Within litter horizons, we observed significant enrichment in Hg concentration and heavier isotopes along the depth, which we hypothesize to result from additional deposition of atmospheric Hg(0) during litter decomposition. Furthermore, Hg isotope signatures in mineral soils closely resemble those of the overlying litter horizons suggesting incorporation of Hg from litter as a key source of soil Hg. The spatial distribution of Hg isotope compositions in mineral soils across all sites is modeled by isotopic mixing assuming atmospheric Hg(II), atmospheric Hg(0), and geogenic Hg as major sources. This model shows that northern sites with higher precipitation tend to have higher atmospheric Hg(0) deposition than other sites, whereas drier sites in the western U.S. tend to have higher atmospheric Hg(II) deposition than the rest. We attribute these differences primarily to the higher litterfall Hg input at northern wetter sites due to increased plant productivity by precipitation. These results allow for a better understanding of Hg cycling across the atmosphere‐forest‐soil interface.

show abstract

Section: Resultsmentioning

confidence: 90%

Mercury isotope compositions across North American forests

Zheng

Obrist

Weis

et al. 2016

Global Biogeochemical Cycles

187

195

View full text Add to dashboard Cite

show abstract

“…2A). These concentrations at the low ng/g level are in the range of mafic-ultramafic rocks worldwide (i.e., 0.2-7.0 ng/g for basalts and peridotite) 12,13 .…”

Section: Resultsmentioning

confidence: 93%

Mantle Hg isotopic heterogeneity and evidence of oceanic Hg recycling into the mantle

et al. 2022

View full text Add to dashboard Cite

The geochemical cycle of mercury in Earth’s surface environment (atmosphere, hydrosphere, biosphere) has been extensively studied; however, the deep geological cycling of this element is less well known. Here we document distinct mass-independent mercury isotope fractionation (expressed as Δ199Hg) in island arc basalts and mid-ocean ridge basalts. Both rock groups show positive Δ199Hg values up to 0.34‰ and 0.22‰, respectively, which deviate from recent estimates of the primitive mantle (Δ199Hg: 0.00 ± 0.10‰, 2 SD)1. The positive Δ199Hg values indicate recycling of marine Hg into the asthenospheric mantle. Such a crustal Hg isotope signature was not observed in our samples of ocean island basalts and continental flood basalts, but has recently been identified in canonical end-member samples of the deep mantle1, therefore demonstrating that recycling of mercury can affect both the upper and lower mantle. Our study reveals large-scale translithospheric Hg recycling via plate tectonics.

show abstract

“…This natural contribution is even smaller in some compartments of the terrestrial environment such are labile organic soils [62]. Recent findings suggest an order of magnitude lower crustal abundance of Hg than previously estimated [63]. However, using uniform basin-scale Hg yields we do not capture elevated inputs in areas more prone to erosion or areas naturally enriched in Hg such as Hg mineral belts and tectonically active areas.…”

Section: Resultsmentioning

confidence: 93%

Toward an Assessment of the Global Inventory of Present-Day Mercury Releases to Freshwater Environments

Kocman

Wilson

Amos

et al. 2017

IJERPH

Self Cite

101

View full text Add to dashboard Cite

Aquatic ecosystems are an essential component of the biogeochemical cycle of mercury (Hg), as inorganic Hg can be converted to toxic methylmercury (MeHg) in these environments and reemissions of elemental Hg rival anthropogenic Hg releases on a global scale. Quantification of effluent Hg releases to aquatic systems globally has focused on discharges to the global oceans, rather than contributions to freshwater systems that affect local exposures and risks associated with MeHg. Here we produce a first-estimate of sector-specific, spatially resolved global aquatic Hg discharges to freshwater systems. We compare our release estimates to atmospheric sources that have been quantified elsewhere. By analyzing available quantitative and qualitative information, we estimate that present-day global Hg releases to freshwater environments (rivers and lakes) associated with anthropogenic activities have a lower bound of ~1000 Mg·a−1. Artisanal and small-scale gold mining (ASGM) represents the single largest source, followed by disposal of mercury-containing products and domestic waste water, metal production, and releases from industrial installations such as chlor-alkali plants and oil refineries. In addition to these direct anthropogenic inputs, diffuse inputs from land management activities and remobilization of Hg previously accumulated in terrestrial ecosystems are likely comparable in magnitude. Aquatic discharges of Hg are greatly understudied and further constraining associated data gaps is crucial for reducing the uncertainties in the global biogeochemical Hg budget.

show abstract

Mercury in some arc crustal rocks and mantle peridotites and relevance to the moderately volatile element budget of the Earth

Cited by 44 publications

References 49 publications

Mercury isotope compositions across North American forests

Mercury isotope compositions across North American forests

Mantle Hg isotopic heterogeneity and evidence of oceanic Hg recycling into the mantle

Toward an Assessment of the Global Inventory of Present-Day Mercury Releases to Freshwater Environments

Contact Info

Product

Resources

About