Science Education News (SEN) Journal 2017 Volume 66 Number 4 December 2017 | Page 27

ARTICLES
Explorers probe Hidden Continent of Zealandia
By Professor Rupert Sutherland, Victoria University, Wellington, N.Z.
The following fascinating article was initially published in
‘The Conversation’ on 11th September, and SEN is grateful
to the author, Professor Rupert Sutherland, for permission
to republish this article, and to ‘The Conversation’ for its
highly-valued policy of encouraging this process, ensuring
maximum exposure of valuable material, (and not merely on
scientific issues) – Ed.
chain of undersea volcanoes, ocean trenches, seamounts and
hydrothermal vents that formed some 40 to 50 million years ago.
Zealandia made global headlines earlier this year when
scientists announced that it counts as a new continent. Now it is
coming under closer scientific scrutiny. We are currently halfway
through an expedition to drill into this vast underwater plateau
of continental crust, and we can already reveal that Zealandia’s
geography changed more dramatically and more recently than
anyone had thought.
[Watch this video]
https://www.youtube.com/watch?v=6qCQAvAXLOU
Earth’s hidden continent
There are seven continents on Earth: Eurasia, North America,
South America, Africa, Antarctica, Australia and now Zealandia.
Zealandia is about two-thirds the size of Australia, but 94% of
it lies deep below the southwest Pacific Ocean. Its only major
landmasses are New Zealand to the south and New Caledonia
to the north. Very little is known about it, because most of it lies
more than a kilometre deep beneath the Pacific Ocean.
The Zealandia continent also encompasses some smaller bits of
land, including Norfolk Island, the Lord Howe group and some
sub-Antarctic islands. These islands were discovered hundreds
of years ago, but the submerged part was only recognised as a
continent in recent decades. It remains sparsely surveyed and
sampled. We have better maps of the Moon. Zealandia exposed
We are a team of 32 scientists from 12 different countries and our
expedition is part of the International Ocean Discovery Program,
which coordinates seagoing explorations of Earth’s history
recorded in sediments and rocks beneath the ocean floor. There is a buzz of excitement on the ship. After more than a month
at sea we are mid-way through our expedition and have drilled
into the seabed at four sites. You can’t beat the old-fashioned
thrill of exploration and discovery!
Our ship, the ‘Joides Resolution’, is a floating village and
laboratory, equipped with a drill rig that can take core samples
from the seafloor. The samples we have collected so far show
clear signs of major geographic changes and volcanic eruptions
that were related to formation of the ‘Pacific Ring of Fire’, a We are re-writing the geological history of Zealandia on our
voyage. Zealandia was first recognised about 50 years ago,
and ideas for how it formed were published then, but the only
previous expedition that has drilled deep enough into the seabed
to collect useful evidence was undertaken in 1971.
A map of the 'new' continent, Zealandia, that shows its size and
extension, with New Zealand and other islands
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SCIENCE EDUCATIONAL NEWS VOL 66 NO 4