Pb isotope geochemistry and reappraisal of Sr-Nd isotopes of the Cerro Morado basic magmatism (Ischigualasto-Villa Union Triassic basin, NW Argentina): Implications for the mantle sources

A new isotopic analysis of alkaline basalts from the Los Baldecitos Formation in Argentina's Ischigualasto-Villa Unión Triassic basin reveals that these rocks originated from a single, uncontaminated mantle source with a PREMA reservoir signature. The study, using Sr-Nd-Pb isotopes, found moderately radiogenic lead compositions and highly radiogenic neodymium values, indicating minimal crustal involvement or ancient crust influence. Contrary to previous suggestions, the data rule out a HIMU component in the mantle source, providing clearer insights into the region's geological history.

Sommer, C. A., Barreto, C. J. S., Lafon, J. M., Lima, E. F. d., Alexandre, F. M., Chemale Jr., F., & Koester, E. (2018). Pb isotope geochemistry and reappraisal of Sr-Nd isotopes of the Cerro Morado basic magmatism (Ischigualasto-Villa Union Triassic basin, NW Argentina): Implications for the mantle sources. Brazilian Journal of Geology, 48(1), 115–126. https://doi.org/10.1590/2317-4889201820170106