Complex eruption processes and deposits of basaltic fissures: insights from the ~37 ka Budj Bim volcanic complex, Southeastern Australia

A rare preservation of a volcanic fissure system, the ~37 ka Budj Bim Volcanic Complex (BBVC) in southeastern Australia, offers unprecedented insights into complex eruption processes. The study reveals five distinct eruption stages characterized by vent-shifting along a dyke-fed fissure and rapid transitions between Strombolian and micro-Plinian activity, interspersed with phreatomagmatism. This complexity, driven by interactions with aquifers and near-surface faults, suggests deeper explosion depths potentially reaching 320 meters. The findings draw parallels with the 2014-2015 Bárðarbunga-Holuhraun eruption in Iceland but highlight increased intricacy due to its intraplate continental setting. This research enhances understanding of volcanic fissure eruption behavior and improves future eruption scenario assessments, particularly for the Newer Volcanics Province (NVP) and similar global systems.

Kavanagh, J. L., Chamberlain, K. J., Hrintchuk, J. A., Mariani, E., Boyce, J., Urbani, S., Havard, T. A., Williams, K. M., & Cas, R. A. F. (2026). Complex eruption processes and deposits of basaltic fissures: insights from the ~37 ka Budj Bim volcanic complex, Southeastern Australia. Bulletin of Volcanology, 88(4). https://doi.org/10.1007/s00445-026-01967-9