Whole rock geochemistry data incl. Major, trace elements and radiogenic isotopes on volcanic rocks from the silicic arc-adjacent Loicas Trough volcanic system, Argentina

In this study, we explore the geochemical characteristics of Pleistocene and Holocene volcanic centres in the Loicas Trough including Tromen Volcano and Domuyo Volcano. The Loicas Trough is an arc-adjacent volcanic province that hosts abundant silicic lava eruptions, situated between the Andean main and back arc in the Southern Volcanic Zone, Argentina. We explore the open system processes occurring in the Loicas Trough through bulk major element, trace element, Pb, Nd, Hf and Sr isotope compositions. The major and trace element bulk compositions were determined on bulk rock finely milled powders using ICPMS. The Pb, Sr and Nd bulk rock isotope compositions were determined on rock chips through MC-TIMS analyses. The Hf-isotope compositions were determined on finely agate milled bulk rock powders using MC-ICPMS analysis. Additionally, we include Ar-Ar ages of alkali feldspar from two lava samples. Our results reveal that the isotopic characteristics of the Loicas Trough lavas are dominated by assimilation. We observe increasingly radiogenic isotope compositions coupled with indices of differentiation, such as silica. Crustal heterogeneity and the amount of assimilation overwhelm potential source variations, and assimilation trends are largely controlled by the residual wallrock mineralogy.

The DIGIS geochemical data repository is a research data repository in the Earth Sciences domain with a specific focus on geochemical data. The repository archives, publishes and makes accessible user-contributed, peer-reviewed research data in standardised form (EarthChem Team, 2022, https://doi.org/10.26022/IEDA/112263) that fall within the scope of the GEOROC database (https://georoc.eu). All submissions of new data will be considered for inclusion in the GEOROC database. It is hosted at GFZ Data Services through a collaboration between the Digital Geochemical Data Infrastructure (DIGIS) for GEOROC 2.0 (https://digis.geo.uni-goettingen.de) and the GFZ German Research Centre for Geosciences.