Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8910592 | Geochimica et Cosmochimica Acta | 2018 | 38 Pages |
Abstract
The lack of correlations of δ66Zn with geochemical indicators of magma differentiation (e.g., MgO, SiO2, and Zn/FeT) indicate that fractionation of olivine, pyroxene, and magnetite has a limited effect on the Zn isotopic compositions of arc magmas. Even though the mantle sources of arc rocks investigated here are strongly affected by AOC-derived fluids and melts that have higher δ66Zn compared to the DMM, we observe no systematic variations of δ66Zn with indicators of subduction components (e.g., Ba/La, Ba/Th, Sr/Y, Hf/Lu and 87Sr/86Sr). This suggests that insignificant transport of Zn from the subducting Pacific slab to the Kamchatka and Central-Eastern Aleutian mantle wedge. Our model calculations suggest that the observed offset of δ66Zn between the mantle and arc magmas can be attributed to isotope fractionation during partial melting with no need for contributions from subduction components.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Jian Huang, Xing-Chao Zhang, Sha Chen, Limen Tang, Gerhard Wörner, Huimin Yu, Fang Huang,