Volcano of classifying magmatic volcanoes is by their frequency of eruption, with those that erupt regularly called active, those that have erupted in historical times but are now quiet called dormant or inactive, and those that have not erupted in historical times called extinct. However, these popular classifications—extinct in particular—are practically meaningless to scientists. They use classifications which refer to a particular volcano's formative and eruptive processes and resulting shapes. There is no consensus among volcanologists on how to define an "active" volcano. The lifespan of a volcano can vary from months to several million years, making such a distinction sometimes
Dormant commission dormant commissions to act as Administrator of the Commonwealth in the absence of a Governor-General. By convention, the longest serving state governor exercises the dormant commission, allowing an assumption of office to commence immediately whenever a vacancy occurs and as long as it exists. For example, when Peter Hollingworth stood aside as Governor-General in May 2003, Tasmanian Governor Guy Green was appointed Administrator until Hollingworth's permanent replacement (Major-Gen Michael Jeffery) was appointed and sworn in. The Australian government can advise the Monarch to revoke any Governor's dormant commission. For example, the dormant commission of Colin Hannah, Governor of Queensland, was