Supplemental Material: Metallogenic fingerprint of a metasomatized lithospheric mantle feeding gold endowment in the western Mediterranean basin

Appendix 1: Petrogenesis of Tallante mantle xenoliths; Appendix 2: Analytical methods; Table S1: Major element compositions of rock-forming minerals in Tallante xenoliths; Table S2: Major element compositions of base-metal sulfides (in wt%); Table S3: trace elements abundances (ppm) of clinopyroxene grains in Tallante xenoliths; Table S4: concentrations (ppm) of chalcophile and siderophile elements in base-metal sulfides.

Supplemental Material: Metallogenic fingerprint of a metasomatized lithospheric mantle feeding gold endowment in the western Mediterranean basin

Appendix 1: Petrogenesis of Tallante mantle xenoliths; Appendix 2: Analytical methods; Table S1: Major element compositions of rock-forming minerals in Tallante xenoliths; Table S2: Major element compositions of base-metal sulfides (in wt%); Table S3: trace elements abundances (ppm) of clinopyroxene grains in Tallante xenoliths; Table S4: concentrations (ppm) of chalcophile and siderophile elements in base-metal sulfides.

Terrestrial planet accretion constrained by isotopes: Implications for Earth-like habitats

<p>Here we discuss terrestrial planet formation by using Earth and our knowledge from various isotope data such as <sup>182</sup>Hf-<sup>182</sup>W, U-Pb, lithophile-siderophile elements, atmospheric <sup>36</sup>Ar/<sup>38</sup>Ar, <sup>20</sup>Ne/<sup>22</sup>Ne, <sup>36</sup>Ar/<sup>22</sup>Ne isotope ratios, the expected solar <sup>3</sup>He abundance in Earth’s deep mantle and Earth’s D/H sea water ratios as an example. By analyzing the available isotopic data one finds that, the bulk of Earth’s mass most likely accreted within 10 to 30 million years after the formation of the solar system. Proto-Earth most likely accreted a mass of 0.5 to 0.6 <em>M</em><sub>Earth</sub> during the disk lifetime of 3 to 4.5 million years and the rest after the disk evaporated (see also Lammer et al. 2021; DOI: 10.1007/s11214-020-00778-4). We also show that particular accretion scenarios of involved planetary building blocks, large planetesimals and planetary embryos that lose also volatiles and moderate volatile rock-forming elements such as the radioactive decaying isotope <sup>40</sup>K determine if a terrestrial planet in a habitable zone of a Sun-like star later evolves to an Earth-like habitat or not. Our findings indicate that one can expect a large diversity of exoplanets with the size and mass of Earth inside habitable zones of their host stars but only a tiny number may have formed to the right conditions that they could potentially evolve to an Earth-like habitat. Finally, we also discuss how future ground- and space-based telescopes that can characterize atmospheres of terrestrial exoplanets can be used to validate this hypothesis.   </p>

Genesis of the mafic granophyre of the Vredefort impact structure (South Africa): Implications of new geochemical and Se and Re-Os isotope data

ABSTRACT This contribution is concerned with the debated origin of the impact melt rock in the central uplift of the world’s largest confirmed impact structure—Vredefort (South Africa). New major- and trace-element abundances, including those of selected highly siderophile elements (HSEs), Re-Os isotope data, as well as the first Se isotope and Se-Te elemental systematics are presented for the felsic and mafic varieties of Vredefort impact melt rock known as “Vredefort Granophyre.” In addition to the long-recognized “normal” (i.e., felsic, >66 wt% SiO2) granophyre variety, a more mafic (<66 wt% SiO2) impact melt variety from Vredefort has been discussed for several years. The hypothesis that the mafic granophyre was formed from felsic granophyre through admixture (assimilation) of a mafic country rock component that then was melted and assimilated into the superheated impact melt has been pursued here by analysis of the two granophyre varieties, of the Dominion Group lava (actually metalava), and of epidiorite mafic country rock types. Chemical compositions, including high-precision isotope dilution–derived concentrations of selected highly siderophile elements (Re, Os, Ir, Pt, Se, Te), and Re-Os and Se isotope data support this hypothesis. A first-order estimate, based on these data, suggests that some mafic granophyre may have resulted from a significant admixture (assimilation) of epidiorite to felsic granophyre. This is in accordance with the findings of an earlier investigation using conventional isotope (Sr-Nd-Pb) data. Moreover, these outcomes are in contrast to a two-stage emplacement model for Vredefort Granophyre, whereby a mafic phase of impact melt, derived by differentiation of a crater-filling impact melt sheet, would have been emplaced into earlier-deposited felsic granophyre. Instead, all chemical and isotopic evidence so far favors formation of mafic granophyre by local assimilation of mafic country rock—most likely epidiorite—by a single intrusive impact melt phase, which is represented by the regionally homogeneous felsic granophyre.