Silver Isotopes in Silver Suggest Phoenician Innovation in Metal Production

The current study presents Ag isotopic values of 45 silver artifacts with known Pb isotopic composition from the Southern Levant. These items originate from seven pre-coinage silver hoards, dating from the Middle Bronze Age IIC to the end of the Iron Age (~1650–600 BCE). These are the earliest silver artifacts analyzed for Ag isotopes; all former studies were performed on coins. All the sampled silver in this study contains relatively unfractionated Ag (−2 ≤ ε109Ag ≤ 1.5) that was more likely produced from hypogene, primary Ag-bearing minerals (e.g., galena and jarosite) and not from native, supergene silver. Four of the sampled hoards containing silver from Anatolia and the West Mediterranean (Iberia and Sardinia) are associated with the Phoenician quest for silver (~950–700 BCE). A significant amount of this Phoenician silver (12/28 items) plots within a narrower range of −0.5 ≤ ε109Ag ≤ 0.5. This is in contrast to non-Phoenician silver, which mostly underwent some degree of fractionation (16/17 items ε109Ag ≥ I0.5I). The results suggest that while all silver was exploited from primary ore sources, the Phoenicians dug deeper into the deposits, reaching ore minerals that did not undergo any weathering-associated fractionation. The results also call for further investigation regarding the influence of sealing and bundling in silver hoards on post-depositional fractionation of Ag isotopes.

Supplemental Material: Detrital zircon provenance of the Cretaceous–Neogene East Coast Basin reveals changing tectonic conditions and drainage reorganization along the Pacific margin of Zealandia

<div>Table S1: Data sources for composite basement terranes. Table S2: Relative proportions of age fractions for composite basement terranes. Table S3: U-Th-Pb isotopic composition of detrital zircon analyzed at the University of Arizona LaserChron Center. Table S4: U-Th-Pb isotopic composition of detrital zircon analyzed at the University California, Santa Cruz. Table S5: Relative proportions of age fractions for Cenozoic East Coast Basin cover stratigraphy. Table S6: Relative proportions of age fractions for Cretaceous East Coast Basin cover stratigraphy. Table S7: Mixture modeling results for detrital zircon samples. Figure S1: Map of all samples from the basement terrane and cover stratigraphy with detrital zircon U-Pb ages. File S1: Systematic analysis of mixture modeling results. <br></div>

Supplemental Material: Detrital zircon provenance of the Cretaceous–Neogene East Coast Basin reveals changing tectonic conditions and drainage reorganization along the Pacific margin of Zealandia

<div>Table S1: Data sources for composite basement terranes. Table S2: Relative proportions of age fractions for composite basement terranes. Table S3: U-Th-Pb isotopic composition of detrital zircon analyzed at the University of Arizona LaserChron Center. Table S4: U-Th-Pb isotopic composition of detrital zircon analyzed at the University California, Santa Cruz. Table S5: Relative proportions of age fractions for Cenozoic East Coast Basin cover stratigraphy. Table S6: Relative proportions of age fractions for Cretaceous East Coast Basin cover stratigraphy. Table S7: Mixture modeling results for detrital zircon samples. Figure S1: Map of all samples from the basement terrane and cover stratigraphy with detrital zircon U-Pb ages. File S1: Systematic analysis of mixture modeling results. <br></div>

Heavy Metal, Rare Earth Element and Pb Isotope Dynamics in Mussels During a Depuration Experiment in the Gulf of Aqaba, Northern Red Sea

Mussels are considered highly efficient marine biomonitors, tracing anthropogenic and natural variations in heavy metals and various organic compounds. While heavy metals depuration processes in biomonitors are of growing interest, less knowledge is available regarding their Pb isotopes and rare earth elements (REEs) accumulation-release dynamics, and their response to short-term anthropogenic and terrigenous perturbations. Here, we report the results of a relocation experiment where a group of mussels (Brachidontes pharaonis) were extracted from a contaminated lagoon in the Gulf of Aqaba, northern Red Sea, and placed in water tanks that were flushed continuously with fresh, uncontaminated seawater. Specimens were removed periodically from the water table over a period of 13 weeks and trace and REEs and Pb isotopic compositions were determined separately for mussel’s shells and soft tissues. The results display a clear decrease over time in the concentrations of various heavy metals and REEs in the soft tissue, in concert with a similar shift in the Pb isotopic compositions toward seawater values. By contrast, the elemental and Pb isotopic composition of the shell presents little change over time. Coupling between the Pb isotopic composition of corresponding soft tissue and shell samples allows back-calculation of the timing and magnitude of abrupt pollution events and presents a novel approach for monitoring short-term pollution events. Nevertheless, given the coastal setting of the studied samples, it is important to consider the effects of terrigenous material on the results. Accordingly, Al-normalized element concentrations, Pb isotopes and calculated Ce anomalies, are used to identify two distinct terrigenous end members controlling the contaminated lagoon and the pristine site. The study demonstrates the potential of using mussels as robust biomonitors of natural and anthropogenic environmental perturbations through the combination between elemental concentrations and the isotopic composition of Pb.

Long-Lasting (65 Ma) Regionally Contrasting Late- to Post-Orogenic Variscan Mantle-derived Potassic Magmatism in the Bohemian Massif

The orogenic development after the continental collision between Laurussia and Gondwana, led to two contrasting associations of mantle-derived magmatic rocks on the territory of the Bohemian Massif: (i) a 340–310 Ma lamprophyre-lamproite orogenic association; and (ii) a 300–275 Ma lamprophyre association of anorogenic affinity. Major types of potassic mantle-derived magmatic rocks recognized in the orogenic and anorogenic associations include: (i) calc-alkaline to alkaline lamprophyres; (ii) alkaline ‘orthopyroxene minettes’ and geochemically related rocks grouped here under the new term lampyrite; and (iii) peralkaline lamproites. These three types significantly differ with respect to mineral, whole-rock and Sr–Nd–Pb–Li isotope composition and spatial distribution. The calc-alkaline lamprophyres occur throughout the entire Saxo-Thuringian and Moldanubian zones, whereas the different types of malte-derived potassic rocks are spatially restricted to particular zones. Rocks of the Carboniferous lamprophyre-lamproite orogenic association are characterized by variable negative εNd(i) and variably radiogenic Sr(i), whereas the rocks of the Permian lamprophyre association of anorogenic affinity are characterized by positive εNd(i) and relatively young depleted-mantle Nd-model ages reflecting increasing input from upwelling asthenospheric mantle. The small variation in the Pb isotopic composition of post-collisional potassic mantle-derived magmatic rocks (of both the orogenic and anorogenic series) implies that the Pb budget of the mantle beneath the Bohemian Massif is dominated by the same crust-derived material, which itself may include material derived from several sources. The source rocks of ‘orthopyroxene minettes’ are characterized by isotopically light (‘eclogitic’) Li and strongly radiogenic (crustal) Sr and may have been metasomatized by high-pressure fluids along the edge of a subduction zone. In contrast, the strongly Al2O3 and CaO depleted mantle source of the lamproites is characterized by isotopically heavy Li and high SiO2 and extreme K2O contents. This mantle source may have been metasomatized predominantly by melts. The mantle source of the lamprophyres may have undergone metasomatism by both fluids and melts.

Pb, Nd, Sr isotopic composition of the Mesoproterozoic mafic intrusions (Udzha paleorift, Northern Siberia)

&lt;p&gt;Geodynamic reconstructions are largely based on information contained in mafic igneous rocks, including dykes and sills. The age and isotope-geochemical characteristics of such rocks are inevitable for understanding of geodynamic history of the Proterozoic cratons. The regions in Siberian Craton, where Precambrian mafic dyke swarms are known are following: Anabar Shield and Olenek Uplifts, Aldan-Stanovoi Shield, SE area of Siberian Craton, and smaller Uplifts on the SW margin of Siberian Craton.&lt;/p&gt;&lt;p&gt;The Udzha paleo-rift is located in the northern part of Siberian Craton between Anabar and Olenek Uplifts is also associated with mafic dyke swarm. These dykes cross-cut the pre-Neoproterozoic sedimentary successions. The age of the largest dyke in Udzha paleo-rift (Great Udzha Dyke) presented by medium-grained dolerite was determined to be 1386 &amp;#177; 30 Ma (Malyshev et al., 2018).&lt;/p&gt;&lt;p&gt;We present new data of Sr, Nd and Pb isotopic composition on the Udzha paleo-rift dykes, determined by TIMS. The initial isotopic composition of Pb in the dykes was obtained using the leaching method by Savatenkov et al., 2019. The Sr isotopic composition of the dykes demonstrates substantial variation (&amp;#949;Sr varies from 8.4 to 110.4). We do not consider this fact as a result of crust contamination, because Nd isotopic composition does not vary significantly (&amp;#949;Nd varies from -1.4 to 0.7). Obtained results indicate that initial for the Udzha paleo-rift dykes melts were generated from two mantle reservoirs of DM and EMII-type. The initial Pb isotopic composition of the dykes reveals EMII source participation in the melts generation too (&lt;sup&gt;206&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb varies from 16.133 to 16.266, &lt;sup&gt;207&lt;/sup&gt;Pb/&lt;sup&gt;204&lt;/sup&gt;Pb varies from 15.343 to 15.458). The presence of enriched component is likely associated with lithospheric mantle, metasomatized by fluids, derived from subducted terrigenous material.&lt;/p&gt;&lt;p&gt;The studies were supported by the Russian Science Foundation project No. 19-77-10048.&lt;/p&gt;&lt;p&gt;References&lt;/p&gt;&lt;p&gt;Malyshev, S. V., Pasenko A. M., Ivanov A. V., Gladkochub D. P., Savatenkov V. M., Meffre S., Abersteiner A., Kamenetsky V. S. &amp; Shcherbakov V. D. (2018): Geodynamic Significance of the Mesoproterozoic Magmatism of the Udzha Paleo-Rift (Northern Siberian Craton) Based on U-Pb Geochronology and Paleomagnetic Data. &amp;#8211; Minerals, 8(12), 555&lt;/p&gt;&lt;p&gt;Savatenkov V. M., Malyshev, S. V., Ivanov A. V., Meffre S., Abersteiner A., Kamenetsky V. S., Pasenko A. M. (2019): An advanced stepwise leaching technique for derivation of initial lead isotope ratios in ancient mafic rocks: A case study of Mesoproterozoic intrusions from the Udzha paleo-rift, Siberian Craton. &amp;#8211; Chemical Geology, 528, 119253&lt;/p&gt;