Lavas or ignimbrites? Permian felsic volcanic rocks of the Tisza Mega-unit (SE Hungary) revisited: A petrographic study.

Permian felsic volcanic rocks were encountered in petroleum exploration boreholes in SE Hungary (eastern Pannonian Basin, Tisza Mega-unit, Békés-Codru Unit) during the second half of the 20th century. They were considered to be predominantly lavas (the so-called "Battonya quartz-porphyry") and were genetically connected to the underlying "Battonya granite." New petrographic observations, however, showed that the presumed lavas are crystal-poor (8-20 vol%) rhyolitic ignimbrites near Battonya and resedimented pyroclastic or volcanogenic sedimentary rocks in the Tótkomlós and the Biharugra areas, respectively.