Australia: The Land Where Time Began

A biography of the Australian continent 

This is lava dome (tholoid) that formed as a small volcanic eruption of silica-rich (soda-trachyte) lava. There was little or no pyroclastic component to the eruption. It has been dated to about 6 million years ago in the Late Miocene. The lava dome formed because of the low viscosity of this lava type . The lava had a lower viscosity than most other Tertiary volcanoes in Victoria. This type of structure is also called a namelon. The present structure of the rock resulted from vertical fractures that were widened by erosion.

Links

1. Volcanoes in Victoria
2. Hanging Rock

Sources & Further reading