Triassic igneous rocks from eastern Slovenia

Authors

  • Stanko Grafenauer
  • Jože Duhovnik
  • Dragica Strmole

Abstract

The Middle Triassic rocks in the eastern Slovenia have all properties of the spilitic keratophyre association. They are accompanied by great quantities of tuffs and tuffites. The extrusive and pyroclastic rocks are interstratified within Ladinian beds. After their formation the rocks were more or less altered, we could found in them even garnets in the surroundings of Bohor. The rocks of the eastern Karavanke, Savinja Alps and Central Alps are relatively poor in mafic components, rich in silica, and in some places rich in alkalies, ordinarily with prevailing potassium varieties. Lava extruded mainly on the land, and partly in the sea. Liparites predominate above dacites, trachytes and andesites, while basalts and spilites are almost absent. In the Sava folds basalts, spilites, andesites and hawaiites by far prevail above liparites and dacites. The rocks are rich in mafic components and poor in silica. Lava was fluent and often submarine eruptions and effusions can be found, with formation of pillow and amygdaloid structures. In alkalic rocks the sodium varieties predominate. Much more than in the western part of Slovenia, here the tuffs, tuff sandstones and tuff limestones occur. The rocks are often unusually rich in lead and zinc. There is no transition between liparite and alkalic rocks on one side, and plagiodacite, andesite, basalt and spilite from the other. Keratophyre is usually older than spilite. In the evolution of magma next to differentiation the partial fusion was very important. Assimilation also probably influenced the rapid variation in some smaller extrusive parts.

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How to Cite

Grafenauer, S., Duhovnik, J., & Strmole, D. (1983). Triassic igneous rocks from eastern Slovenia. Geologija, 26(1), 189–241. Retrieved from https://www.geologija-revija.si/index.php/geologija/article/view/536

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