A tear in the sea floor 7km deep just north of Australia could cause disastrous earthquakes and tsunamis.
The tear in the Earth's crust is in the Banda Sea, near Indonesia, and measures about 60,000sq km - roughly the size of Tasmania.
Geologists have now discovered the tear is one of the biggest faults on the planet and is running through the Ring of Fire, an area in the Pacific Ocean where a huge number of earthquakes and volcanic eruptions occur.
According to the United States Geological Survey, 90 per cent of the world's earthquakes and 81 per cent of the world's worst earthquakes occur along the Ring of Fire.
The ring extends from New Zealand, around the top of Australia and past Indonesia. It curls around Japan and down the West Coast of the United States before ending at the bottom of South America.
On November 14 Kaikoura was struck by a magnitude 7.9 earthquake that casued widespread damage and killed two people.
On November 22, an earthquake with a magnitude of 6.9 shook the Japanese coast of Fukushima prefecture and tsunami waves followed not long after.
This month, 84,000 people were left homeless after an 6.5 magnitude earthquake struck western Indonesia. The earthquake killed more than 100 people.