Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5783218 | Geochimica et Cosmochimica Acta | 2017 | 19 Pages |
Abstract
For sulfide-silicate partitioning at 1.5 GPa and 1400 °C we obtain DNd/DSm of about 1.4 and DTh â¼Â 0.1DU. With increasing temperature the differences between these geochemically similar element pairs decreases such that, at 2100 °C DNd/DSm is 1.0 and DTh/DU is about 0.3. We used these results, together with DU and DSm to model addition of a putative Mercury-like component (with FeS core) to early Earth. We find that the 1400° results could lead to a significant (â¼11 ppm) 142Nd anomaly in silicate Earth and add >8 ppb U to the core, but lead to an unreasonably high Th/U of silicate Earth (4.54). Based on the 2100 °C results the 142Nd anomaly would be 0 but addition of the sulfur-rich body could add up to 10 ppb of U to the core, generating, when the accompanying 21 ppb Th is also considered, â¼3 TW of the energy required for the geodynamo. In this case, the Th/U ratio of silicate Earth would approximate 4.3, within the range of some estimates.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Anke Wohlers, Bernard J. Wood,