The researchers, whose findings were published in the journal
Nature Hazards, said the one cubic kilometre slab in the Coral
Sea – dubbed the Noggin Block – "eventually will collapse". The
ominous slab was discovered by geologists who have been using
3-D mapping techniques to build a picture of the sea floor along
the deepest parts of the reef. "It is a pretty big chunk of sea-
floor [in] the very slow, early stages of starting to break away
from the edge of the Great Barrier Reef," said Dr Robin Beaman,
a marine geologist at James Cook University. "If it were to
break away catastrophically, that is break away really quickly,
what that would do is it would create a surface wave above it.
It would actually cause a tsunami. That tsunami would travel
across the Great Barrier Reef, it's about 70 kilometres
offshore, and it would impact the local area, the North
Queensland area." The Noggin Block, perched on the edge of the
continental shelf, is the remnant of an ancient underwater
landslide. Dr Beaman said the sla