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The small yellow section in the middle labelled DSPM is the lost proto-microcontinent that never truly formedCredit: cdn.com
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The microcontinent is lurking below the deep waters of the Davis Strait, which separates Canada and GreenlandCredit: Getty Images
Evidence of the continental mishap was found beneath the Davis Strait.
This is an arm of the Arctic Ocean north of the Labrador Sea between Canada and Greenland.
Scientists say the seafloor beneath the waterway is “anomalously thick” – and now they know why.
It’s the eerie remains of what experts are calling the Davis Strait Proto-Microcontinent (or DSPM)
The 12- to 15-mile thick segment of crust lies beneath the strait, which gets as deep as 6,500 feet in parts.
“We propose that the Davis Strait High and the surrounding region of thick continental crust represents a proto-microcontinent,” said Luke Longley, of the University of Derby, in a study published in Gondwana Research.
A microcontinent is a piece of continent that broke off from a main continental mass to become its own distinct chunk.
The “proto” part means that it didn’t achieve “full crustal separation”, according to scientists.
It’s all linked to the great pulling-apart of North America and Greenland, which took place 120 million years ago.
And this process was supercharged around 61 million years ago, with the floor below the Davis Strait spreading more quickly.
World-first ‘Earth timelapse’ shows continents moving over past 100million years – find your ancient home on stunning new map
Another three to five million years later, the DSPM was created.
Ultimately North America and Greenland (which is a European territory, but physically part of the North American continent) didn’t fully split apart.
This process largely ended 48 million years ago, when a fault formed that created a boundary that stopped the rifting “before continental break-up could occur”, the scientists said.
And around 33 million years ago, seafloor spreading meant Greenland rotated and collided with Canada’s Ellesmere Island, totally ending the shift.
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The Davis Strait lies over a region of submerged land where North America and Greenland were splitting – but the breakaway never finishedCredit: Getty Images
So the DSPM is just a small chunk of a continent that could’ve formed as part of the break-up – but never truly did.
The North American continent itself is enormous, covering around 9.54 million square miles.
It represents around 16.5% of Earth’s land, and is the third-largest continent by size after Asia and Africa.
The massive continent – which still does include Greenland – has a population of more than 592 million people.
CONTINENTAL CONFUSION – THE DIFFERENT LISTS
There are several ways to categorize continents. Here are just a few…
Continuous Landmasses (x4):
Afro-EurasiaAmericaAntarcticaAustralia
Physiographic Regions (x5):
AfricaEurasiaAmericaAntarcticaAustralia
Geological Continents (x6):
AfricaEurasiaNorth AmericaSouth AmericaAntarcticaAustralia
United Nations continental regions (x6):
AfricaAsiaEuropeAmericaAntarcticaAustralia
Approximate “parts” of the world (x7):
AfricaAsiaEuropeNorth AmericaSouth AmericaAntarcticaAustralia
It was originally part of the Pangaea supercontinent.
But North and South America split off from Europe and Africa around 200 million years ago.
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Publish date : 2024-07-26 05:23:00
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