Basalt Organ

The Basalt Organ is a natural wonder.

Description
Jackson Creek, which meets with Deep Creek to become the Maribyrnong River, has slowly worn a deep valley in the basaltic plain formation of hard, dark rock revealing the old volcanic geological formations, such as the hexagonal basalt columns known as the "Organ Pipes". The lava deposit in the bed of the creek is of the order of 70 metres.

As the lava cooled over several years, the interior molten lava got insulated and developed into undisturbed columns of basalt (with uniform composition) as the lava heat dissipated.