Permo-Triassic rift-related magmatism in the Dinarides produced an intrusive gabbro-diorite-syenite-granite formation and an extrusive basalt-andesite-dacite formation with abundant pyroclastic rocks. They are spatially and genetically related to Late Permian to Norian rift-related sedimentary formations of the Adriatic-Dinaridic carbonate platform (ADCP). The volcanic and pyroclastic rocks are interlayered with fossiliferous sediments that range between the Late Permian and Middle Norian; the plutonic rocks, which are intrusive into Late Paleozoic and Scythian-Anisian sediments, have radiometric ages ranging between 262 and 212 Ma. Based on major and trace element contents, rocks of the Permo-Triassic magmatic association originated by fractional crystallization from primitive alkalic basalt to olivine tholeiite melts. Volcanic rocks were affected by strong ocean-hydrothermal metamorphism. Initial 87Sr/86Sr ratio of 0.703 and d18O of 5.6‰ of the most primitive rocks indicate an upper mantle origin. Most initial 87Sr/86Sr ratios range between 0.704-0.707, indicating a slight degree of crustal contamination. The Permo-Triassic igneous rocks of the Dinarides represent a specific and autonomous paleorift-related association, which cannot be correlated with the magmatic associations either from recent oceans or with alkali rocks from the Cenozoic African rift and Permian Oslo graben.
Authors:Dražen Balen, János Haas and Sándor Kovács
The present issue is devoted to the memory of Professor Jakob Pamić, who for a long time, until his death, was a very active member of the Advisory Board of the Acta Geologica Hungarica and provided great efforts toward a better understanding of the geology of the Pannonian Basin and the surrounding mountain ranges.