The fate of subducting carbon tracked by Mg and Zn isotopes: A review and new perspectives

Liu, Sheng‐Ao; Qu, Yuan-Ru; Wang, Zezhou; Li, Meng-Lun; Yang, Chun; Li, Shuguang

doi:10.1016/j.earscirev.2022.104010

Cited by 41 publications

(23 citation statements)

References 173 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some kinds of Mg-rich carbonates have significantly high Zn contents (e.g., 147p.p.m in dolomite and 449p.p.m in magnesite) 47 . Such Mg-rich carbonates are more stable in the subduction zone 3 , 48 , and a considerable proportion of them has the potential to be retained in subducted slabs and finally introduced into the deep mantle, e.g., the mantle transition zone (410–660 km) 48 , 49 . Consequently, recycled carbonate, along with recycled oceanic crust, is a suitable candidate to produce metasomatic carbonatite melts (with variable proportions of silicate composition), which inherit the high δ 66 Zn signature.…”

Section: Resultsmentioning

confidence: 99%

Zinc isotopic evidence for recycled carbonate in the deep mantle

et al. 2022

View full text Add to dashboard Cite

Carbonate, the major carbon reservoir on Earth’s surface, can enter into the mantle by subduction. However, evidence for recycled surficial carbonates in the deep mantle is still scarce. Ocean island basalts from Cook-Austral islands and St. Helena Island, widely called HIMU basalts because of their high μ = 238U/204Pb sources, are thought to be fed by mantle plumes originating in the lower mantle. Here we report exceptionally high δ66Zn values (δ66Zn = 0.38 ± 0.03‰) of these HIMU lavas relative to most published data for oceanic basalts (δ66Zn = 0.31 ± 0.10‰), which requires a source contributed by isotopically heavy recycled surficial carbonates. During subduction of the oceanic lithosphere, melting of mixed surficial carbonates and basaltic crust in the deep mantle generates carbonatite melts, which metasomatizes the nearby mantle and the resultant carbonated mantle ultimately evolves into a high-δ66Zn HIMU source. High-δ66Zn signatures of HIMU basalts, therefore, demonstrate that carbonates can be transported into Earth’s deep mantle.

show abstract

Section: Resultsmentioning

confidence: 99%

Zinc isotopic evidence for recycled carbonate in the deep mantle

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Studies of basaltic magmatic differentiation series have demonstrated that Zn isotopes are not substantially modified (<0.1 ‰) during fractional crystallisation processes (Chen et al, 2013), but that significant fractionation (≥0.1 ‰) in δ 66 Zn is likely to occur during mantle partial melting (Wang et al, 2017). Partial melting processes can explain δ 66 Zn variations in arc lavas (Huang et al, 2018), whereas it has been argued that δ 66 Zn variations in some mantle-derived basaltic rocks reflect contributions from distinct sources, including recycled carbonate (Beunon et al, 2020;Liu et al, 2022).…”

Section: Introductionmentioning

confidence: 99%

A partial melting control on the Zn isotope composition of basalts

Day¹,

Moynier²,

Ishizuka³

2022

Geochem. Persp. Let.

View full text Add to dashboard Cite

Basaltic partial melts are produced in a range of tectonic settings, including fluid-assisted melting above subduction zones, decompression melting at ridges and thermally driven melting above mantle plumes. To examine the role of partial melting on Zn, isotope and abundance data are reported for modern large-degree partial melts of the mantle represented by 22 mid-ocean ridge basalts (MORB) from three ocean basins and the first data for boninites. Boninites have some of the lowest Zn abundances of all terrestrial basalts and Zn isotope compositions (δ 66 Zn = þ0.21 ± 0.06 ‰), generally lighter than for MORB (δ 66 Zn = þ0.28 ± 0.06 ‰). Accounting for partial melting, komatiites, boninites and MORB derive from mantle sources with δ 66 Zn of ∼0.16 ± 0.06 ‰. Lower-degree partial melts, such as alkali basalts, can have higher δ 66 Zn, with up to ∼0.4 ‰ variation possible from partial melting of distinct peridotite mantle sources. Partial melting of fertile lherzolitic and depleted harzburgitic mantle sources can generate significant Zn isotope variability and should be evaluated prior to ascribing crustal, enriched or lithological components to mantle reservoirs from Zn compositions of planetary basalts.

show abstract

“…Liu & Li, 2019; S.‐A. Liu et al., 2022), the high δ 66 Zn value (0.43‰) and MgO content of sample DMP528 are more likely to be caused by the involvement of high‐Mg carbonates (e.g., magnesite). Combined with a lower 143 Nd/ 144 Nd ratio (0.510991) of sample DMP528 compared to alter oceanic crust and seawater (Hauff et al., 2003), this evidence mentioned above indicates that it may represent a fossilized sediment melt formed by the melting of metasediments (containing high‐Mg carbonates and phengite) with upper continental crust components (radiogenic Nd isotopic composition).…”

Section: Discussionmentioning

confidence: 98%

Tracing Sediment Melt Activity in the Sub‐Continental Lithosphere: Insights From Zn‐Fe Stable Isotopes

Zhang

Liu

et al. 2023

JGR Solid Earth

View full text Add to dashboard Cite

Recycling of upper crustal sediments through slab subduction contributes to sub‐continental lithospheric refertilization and heterogeneity. However, the nature of recycled upper crustal components is unclear and direct evidence for sediment melt activity in the sub‐continental lithosphere is lacking. Here, we integrate major and trace elements, zircon U‐Pb dating, Sr‐Nd‐Zn‐Fe isotopic compositions of clinopyroxenites (crust‐mantle boundary) and a “glassy” xenolith from the North China Craton to relate their petrogenesis to the potential recycling of upper continental crust and provide direct insight into the sediment melt‐rock interaction. The clinopyroxenites have relatively uniform δ56Fe values (the permil deviation of the 56Fe/54Fe ratio from the IRMM014; −0.05‰–0.07‰, except for one outlier) and are not affected by melt metasomatism. The clinopyroxenites have highly variable whole‐rock δ66Zn values (the permil deviation of the 66Zn/64Zn ratio from the JMC‐Lyon standard) between 0.04‰ and 0.46‰, that closely correlate with Rb/La, K/U, Ba/Th, and Th/Nb ratios, and generate arrays that trend toward a composition similar to the “glassy” xenolith. The “glassy” xenolith has a high δ66Zn value (0.43‰ ± 0.05‰, 2SD) and a significantly low 143Nd/144Nd ratio (0.510991). This evidence implies that the “glassy” xenolith may represent a quenched sediment melt formed by the melting of carbonate‐bearing terrigenous sediments that may also be responsible for the metasomatism of clinopyroxenite xenoliths. The geochemical evidence from the “glassy” and clinopyroxenite xenoliths provides a direct evidence for the activity of sediment melt with upper continental crust components in the sub‐continental lithosphere.

show abstract

The fate of subducting carbon tracked by Mg and Zn isotopes: A review and new perspectives

Cited by 41 publications

References 173 publications

Zinc isotopic evidence for recycled carbonate in the deep mantle

Zinc isotopic evidence for recycled carbonate in the deep mantle

A partial melting control on the Zn isotope composition of basalts

Tracing Sediment Melt Activity in the Sub‐Continental Lithosphere: Insights From Zn‐Fe Stable Isotopes

Contact Info

Product

Resources

About