Australia is the only continent without an active volcano because the area does not have any plate boundaries. The Earth’s surface is made of several plates, and plate boundaries are the areas on Earth where its plates are adjacent to one another. Volcanoes are at the highest risk of eruption the closer they are located to plate boundaries. While Australia has evidence of having had active volcanoes within the past 60 million years, it is thought that the continent shifted over time away from plate boundaries. The closest active volcanoes to Australia are in Papua New Guinea, Indonesia, the Philippines, and New Zealand.
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