Generation of Arc-Like and OIB-Like Magmas Triggered by Slab Detachment in the Eastern Mexican Alkaline Province: Petrological Evidence from the Cenozoic Sierra de San Carlos-Cruillas Complex, Tamaulipas

Abstract The origin of the Eastern Mexican Alkaline Province has been explained by landward arc migration and subsequent asthenospheric upwelling after slab roll-back Farallon Plate. In this work, we present new petrographic, mineral chemical, geochemical, geochronological data Sierra de San Carlos-Cruillas (SSCC), one most important complexes in province. This information, together with published data, helped us to reinterpret tectonic processes operating during generation province, as well mantle sources involved partial melting process. Detailed geochemical analysis suggests participation two types metasomatized regions: a lithospheric source modified past subduction an slightly affected carbonatite-related metasomatism. Variations degrees controlled extent magma enrichment latter. Major trace element geochemistry, field relations, evinced older post-orogenic setting related arc-like rocks (Eocene) younger intraplate extensional environment associated all enriched igneous (Oligocene-Miocene). Bivariate diagrams SiO2-trace ratios multi-element patterns indicate that magmas from SSCC complex dominantly evolved through fractional crystallization limited crustal contribution. Petrographic chemistry features suggest some these experienced open-system (e.g. recharge events) dynamic magmatic feeding system. contrast traditional petrotectonic model, propound passage foundering Hess conjugate under northeastern Mexico resulted its eclogitization triggered tearing succeeding detachment. latter process occasioned recognized sources, thus generating magmatism.