A new study has uncovered the mysterious processes that gave rise to a bizarrely-shaped plume beneath Iceland.

Scientists estimate the Icelandic mantle plume, which played a major role in the geologic and oceanographic evolution of the region, has about five finger-like appendages extending from its center.

The new analysis suggests the phenomenon is caused by the injection of hot rock into a layer of Earth roughly 100 kilometers (62 miles) beneath the surface, creating the strange radial tendrils as it spreads.

Scientists estimate the Icelandic mantle plume, which played a major role in the geologic and oceanographic evolution of the region, has about five finger-like appendages extending from its center

Scientists estimate the Icelandic mantle plume, which played a major role in the geologic and oceanographic evolution of the region, has about five finger-like appendages extending from its center

Scientists estimate the Icelandic mantle plume, which played a major role in the geologic and oceanographic evolution of the region, has about five finger-like appendages extending from its center

WHAT’S CAUSING IT? 

In the study, the researchers suspected the finger-like structures may be the result of a phenomenon known as ‘Saffman-Taylor instability.’

The term describes the ‘fingering’ that occurs as a result of viscosity differences when one fluid is injected into another.

The researchers found that, when hot rock from the Iceland plume enters the athenosphere, a layer roughly 100 km thick beneath the lithospheric plate, the viscosity differences cause it to stem outward like fingers.

Plumes carry hot rock from deep beneath the surface, and in this case, ‘had a significant effect on the stratigraphic evolution of the North Atlantic Ocean,’ the authors explain in the study, published to Earth and Planetary Science Letters.

As this rock is more buoyant, the researchers say it may have helped keep Scotland and western Norway above sea level, according to New Scientist, despite the crust in these areas being ‘considerably shallower than expected.’

In the study, the researchers suspected the finger-like structures may be the result of a phenomenon known as ‘Saffman-Taylor instability.’

The term describes the ‘fingering’ that occurs as a result of viscosity differences when one fluid is injected into another.

The researchers estimated the distribution of temperature and viscosity within the asthenosphere layer beneath the area.

This layer is roughly 100 kilometers wide, and sits beneath the lithospheric plate.

While this phenomenon typically forms a more symmetrical pattern in the lab, it’s thought that the crust beneath nearby Greenland is preventing it from spreading as far on the western side, giving it an uneven distribution

While this phenomenon typically forms a more symmetrical pattern in the lab, it’s thought that the crust beneath nearby Greenland is preventing it from spreading as far on the western side, giving it an uneven distribution

In the study, the researchers suspected the finger-like structures may be the result of a phenomenon known as ‘Saffman-Taylor instability'

In the study, the researchers suspected the finger-like structures may be the result of a phenomenon known as ‘Saffman-Taylor instability'

While this phenomenon typically forms a more symmetrical pattern in the lab, as shown left, it’s thought that the crust beneath nearby Greenland is preventing it from spreading as far on the western side, giving it an uneven distribution.

And, the zone is comprised of relatively free-flowing rock, according to New Scientist.

The researchers found that, when hot rock from the Iceland plume enters the layer, the viscosity differences cause it to stem outward like fingers.

While this phenomenon typically forms a more symmetrical pattern in the lab, it’s thought that the crust beneath nearby Greenland is preventing it from spreading as far on the western side, giving it an uneven distribution.

On the other side, though, these ‘fingers’ reach as far away as Scotland and Norway, New Scientist reports.

Based on their comparisons to the laboratory experiments on the phenomenon, the researchers say the Saffman-Taylor instability is likely what’s at play beneath Iceland.

A new study has uncovered the mysterious processes that gave rise to a bizarrely-shaped plume beneath Iceland. Plumes carry hot rock from deep beneath the surface, and ‘had a significant effect on the stratigraphic evolution of the North Atlantic Ocean,’ the authors wrote

A new study has uncovered the mysterious processes that gave rise to a bizarrely-shaped plume beneath Iceland. Plumes carry hot rock from deep beneath the surface, and ‘had a significant effect on the stratigraphic evolution of the North Atlantic Ocean,’ the authors wrote

A new study has uncovered the mysterious processes that gave rise to a bizarrely-shaped plume beneath Iceland. Plumes carry hot rock from deep beneath the surface, and ‘had a significant effect on the stratigraphic evolution of the North Atlantic Ocean,’ the authors wrote

And, it could be responsible for the existence of areas such as the Scottish Highlands.

The find, they say, has ‘significant implications’ for the evolution of the area’s topography.

‘The temporal evolution of this circulation has significant consequences for regional exhumation, for deposition of clastic sediments, for halokinesis in the southern North Sea, and for source rock maturation,’ the researchers wrote.

‘It also helps to account for the development of youthful peneplains whose age and origin are much debated.

‘Finally, a rapidly evolving and irregular plume planform appears to have had a significant influence in moderating the overflow of North Atlantic Deep Water and its ancient precursor.’ 

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