Byaduk - Tumuli (Lava Blisters)
Located between Wallacedale and Byaduk in the Harman Valley, this feature is believed to be one of only three sites in the world where tumuli (lava blisters) or dome-shaped mounds are found. (The other sites are in Africa and Iceland).
The tumuli are circular mounds or hummocks of rock up to 10 metres high and 20 metres in diameter. When the surface of a lava flow quickly crusts over, pressure in the liquid lava beneath can cause the crust to rise. Generally, it forms irregular broad mounds and hollows known as Stony Rises, but occasionally, it creates smaller, steep-sided domes called tumuli. These are believed to have formed where the pressure was localised, or there was a small soft spot in the crust. Usually, the dome is completely solid, but occasionally, part of the liquid core drains out and the top of the dome subsides to
leave a central hollow or doughnut-shaped mound.
Location
Old Crusher Road, Byaduk 3301 Map
Web Links
→ Tumuli (Lava Blisters) (PDF)
