A metasomatized lithospheric mantle control on the metallogenic signature of post-subduction magmatism.

Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems.

Improved Precision and Accuracy of Quantification of Rare Earth Element Abundances via Medium-Resolution LA-ICP-MS.

Laser ablation ICP-MS enables streamlined, high-sensitivity measurements of rare earth element (REE) abundances in geological materials. However, many REE isotope mass stations are plagued by isobaric interferences, particularly from diatomic oxides and argides. In this study, we compare REE abundances quantitated from mass spectra collected with low-resolution (m/Δm = 300 at 5% peak height) and medium-resolution (m/Δm = 2500) mass discrimination.

Sulfur and metal fertilization of the lower continental crust.

Mantle-derived melts and metasomatic fluids are considered to be important in the transport and distribution of trace elements in the subcontinental lithospheric mantle. However, the mechanisms that facilitate sulfur and metal transfer from the upper mantle into the lower continental crust are poorly constrained. This study addresses this knowledge gap by examining a series of sulfide- and hydrous mineral-rich alkaline mafic-ultramafic pipes that intruded the lower continental crust of the Ivrea-Verbano Zone in the Italian Western Alps.