Published: 2026-01-30
Submitted manuscript to GONDWANA RESEARCH
We just submitted a manuscript entitled: "Acidic magmatism at the Adria–Europe junction during the waning of Neotethys: Geochemical and geochronological insights from the Sava Zone, Pannonian Basin (Croatia)". The abstract is as follows: The timing of the Neotethys closure in southeastern Europe is controversial and was predominantly placed after the Late Cretaceous, when two magmatic belts were active: the Sava Zone (SZ) with alkaline affinity and the calc-alkaline Apuseni-Banat-Timok-Srednogorie belt (ABTS). We present new data on Late Cretaceous (~78 Ma – 84 Ma) igneous rocks from the subsurface of the Pannonian Basin (Croatia), covering the junction between lower-plate Adria (Dinarides) and upper-plate Europe (Tisia mega-unit). These rocks include A-type granites and syenite (U-Pb zircon ages 80 ± 1.0 Ma, 83.7 ± 0.6 Ma and 78.8 ± 0.7 Ma), as well as I-type granodiorite (79.3 ± 1.1 Ma) in contact with hybrid intermediate rock and microgranular mafic enclaves, generated by magma-mixing. The zircon Hf-isotopic composition indicates a strong influence of a juvenile component in A-type rocks (εHf(i)= +13.5 to -0.8) and a more pronounced crustal influence in I-type granodiorite (εHf(i)= +6.1 to -52.9). Both suites are emplaced in the upper crust of the Tisia megaunit. The A-type granites were formerly considered as a part of the suture situated in the lower plate, but the orthogneiss with Late Permian A-type protolith (U-Pb zircon age 257 ± 2.6 Ma, εHf(i)=+3.2 to -20.0) testifies their affiliation to the Tisia megaunit. Although the I-type granodiorite resembles subduction-related granitoid, less evolved members display enrichment in HFSE/LILE, with relatively high TiO2, pointing to an origin from more alkaline magmas. A-type magmas were derived from fractionation of alkaline to tholeiitic basic magmas mixed with crustal partial melts. Both suites display similarities with the SZ and point to a high-temperature event related to asthenospheric upwelling. New data presented in this paper reinforce the idea of the Neotethys complete consumption by the Late Cretaceous, and indicate complex (post-)collisional processes as a trigger for magmatism, such as slab-roll back or slab-break off and delamination.