In this paper the first quantitative description and volcanological interpretation is given of the Badacsony Hill, the latter being the most well-known butte of the Bakony–Balaton Highland Volcanic Field (BBHVF). The pyroclast/lithics ratio of the pyroclastics was investigated by using point-counting image analysis methodology on the surfaces of hand-cut specimens. The isometrical shape of different grains allowed the obtained 2D data to be converted to 3D volume data. By using this methodology it was possible to infer the relative depth of explosions with respect to the synvolcanic surface and the syneruptive morphology; moreover, the effusive and explosive phases of the volcanism could be identified. The results of point-counting image analysis and the position and extent of the phreatomagmatic sequence on the Badacsony Hill imply that the Badacsony volcano was a monogenetic (probably polycyclic) tuff ring or shallow maar volcano. Such volcanism is associated with the interaction of hot, molten material with groundwater, and this triggers shallow explosions. The low amount of accidental lithics within the deposits confirms the tuff ring scenario; however, such a low amount of accidental lithics could also be observed within deposits from shallow maars when these were formed on a soft, unconsolidated basement. Such an alternative model is envisaged for Badacsony. The development of the volcanism can be divided into explosive and effusive phases, based on the different composition and on the relative stratigraphic position of the respective phreatomagmatic sequences. Based on these results the present study proposes a volcanic evolution model. Given the scarcity of volcanological data on the Badacsony Hill, the results presented here could give a basis for further regional volcanological investigations.
|Translated title of the contribution||The phreatomagmatic pyroclastic sequence of the Badacsony Hill: Implications for the processes and landforms of monogenetic basaltic volcanism|
|Number of pages||14|
|Publication status||Published - Jan 1 2017|
ASJC Scopus subject areas
- Geochemistry and Petrology