Some of them are up to 10 meters high and 20 meters in diameter.
These mounds are known as tumuli or lava blisters.
Tumuli are formed in slow-moving lava fields.
A tumulus near Byaduk, in Victoria, Australia.
In the Harman Valley today, there are dozens of tumuli consisting of bare rocks.
The best examples are located on Old Crusher Road, in the town of Byaduk.
Other places where you’re free to see tumuli are Iceland, Hawaii and Argentina.
A volcanic blister (tumulus) just off Old Crusher Road, near Byaduk, Victoria, Australia.
Photo credit:Ryan Lackey/Wikimedia
A tumulus in Hafnarfjordur, Iceland.
Photo credit:Banco de Imagenes Geologicas/Flickr
Sources:www.geology.sdsu.edu/Wikipedia/www.visitgreaterhamilton.com.au/Intraplate Volcanism
