A Lava Blister refers to a collection of peculiar clusters popularly referred to as the Lava Tumuli, or the ‘blisters’. These unique circular mounds that rise up to 10 metres in the air are the result of lava flow.
The Lava Blister is one of three unique sites across the world where this natural phenomenon occurs, making this a popular attraction in the Grampians. The other two are located in Iceland and Africa.
Lava Blister, Location of Tumuli in the Grampians Victoria
Geographically, the tumuli are formed when lava flow spreads and forms a thin crust. The accumulation of pressure beneath the crust causes it to rise to the surface while thickening the crust. Some of the tumuli crack open releasing hot lava and resulting in characteristic bulges. In the end, the whole mass solidifies resulting in the characteristic unique formations that you see today.
Visitors need to note that this is only an observation site and that no walking trails have been established in the region. Additionally, since the tumuli are located on private ground and have been fenced off, they can only be observed from a distance.