New research has finally shed light on the mysterious and sudden upward motions of the Earth's crust in the vicinity of the South Pole. A team of researchers from various institutions and countries have gotten to the bottom of the strange geological events in the Northern Antarctic Peninsula.
At first glance, Antarctica seems like an unchanging land of ice and snow. Deep underneath the ice however, massive geological forces are in action. To study this phenomenon, the team of researchers led by scientists from the Newcastle University has gathered data on Antarctica using GPS tracking systems. The team was able to gather data using seven different GPS stations throughout the Northern Peninsula of Antarctica. Previous studies on the subject matter have brought to light the "rebounding effect" of the Earth's crust in the region. Moreover, these earlier studies also pointed to climate change as one of the causes of the phenomenon.
Due to the increased melting of ice from global warming, the shrinking ice sheet has caused changes in the ground underneath. However, these changes were thought to be an instant and elastic movement of the crust that was soon followed by a gradual uplifting of the crust over a period of a few thousand years. The GPS data gathered by the researchers showed that the ground in the area was rising much faster than previously thought. The team's measurements suggest that uplifting process pushes up the ground by around 15mm per year. The number is much higher than what the previous studies suggested.
"You would expect this rebound to happen over thousands of years and instead we have been able to measure it in just over a decade. You can almost see it happening which is just incredible," said Grace Nield, the study's lead researcher from the Newcastle University. "Because the mantle is 'runnier' below the Northern Antarctic Peninsula it responds much more quickly to what's happening on the surface."
Due to the collapsing of several massive ice shelves in Antarctica, the ice sheets covering the ground has lost a significant amount of ice mass, which caused the "bouncing" effect of the Earth's crust. Scientists have likened the phenomenon to a stretched section of elastic such as a rubber band. However, the scientists found discrepancies in the amount of ice loss and the uplifting of the ground.
For now, the scientists were able to gather data about the vertical deformation of the crust. The team is now looking to gather data regarding the horizontal motion of the ground underneath Antarctica. Gathering both horizontal and vertical data will help give the scientists an understanding of the three dimensional aspects of the phenomenon. The team published its findings in the online journal Earth and Planetary Science Letters.
"Seeing this sort of deformation of the Earth at such a rate is unprecedented in Antarctica," said Newcastle University Geophysical Geodesy professor Peter Clarke. "What is particularly interesting here is that we can actually see the impact that glacier thinning is having on the rocks 250 miles down,"
