Researchers have stumbled upon the remains of a massive lake from the ancient times in Greenland. The lake is several metres beneath the ice sheet in the northwest part of Greenland. It is presumed to several thousands if not millions of years old.
Rarest ‘Fossil Lake Bed’
The newly found massive ‘fossil lake bed’ is a phenomenon that was never spotted until now, in this cold part of the world. We know that the humongous ice sheet in Greenland has many surprises stored beneath it while it is rapidly losing it mass. In 2019, scientists reported the presence of 50 subglacial lakes below the ice sheet. These lakes are bodies of liquid water that was once ice, stuck between the bedrock below and ice sheet above.
The lake that was found now, however, is completely different than these subglacial lakes. It is an old lake basin, stretching for several metres, dry and now filled with sedimentary infill. The infill consists of loosened rock gauging up to 1.2 kms in thickness and then enveloped by another 1.8 kms of ice. During the formation of the lake, the researchers predict that the area had no ice and the basin would have supported a huge lake that spread over an area of nearly 7100 sq. kms. Its nearly the same size as the total area of US states of Delaware and Rhode Island.
The lake would have held approximately 580 cu. kms of water and was sourced by a minimum of 18 ancient streams. These streams were once present on the northern side of the lake bed. We still don’t know how ancient this lake is, but we can find more info about it by analyzing the samples of loose rock that is present within its basin. It can act as a huge time capsule of ancient sediment that was preserved for several years. It can help us simulate the environment that Greenland had several years ago.
The Loose Rocks Can Reveal Vital Data About The Ice Sheet
Lead researcher and glacial geophysicist, Guy Paxman from Columbia University says, “It could be an important reservoir of data in an area that is, at present, completely covered and inaccessible. If we somehow get samples of those sediments in the lake basin, they could reveal information about the presence or absence of ice.” The massive lake bed is called as ‘Camp Century Basin’. It received it’s name from a historic military research base in its vicinity that was discovered by observations from NASA’s Operation IceBridge mission.
The team believes the formation of the lake occurred in warmer times as the bedrock displaced due to the presence of a fault line beneath it which now remains dormant. Another alternate explanation is glacial erosions that may have caused the basin to form over a period of time. In any event, the team firmly believes that the ancient lake basin holds a vital sedimentary record. If we can somehow reach deep below the ice to sample and analyze it, we may be able to found it if the lake was free from ice or was covered in it. It can also help reveal past climatic and environmental conditions in the particular region.
Paxman says, “We are trying to know how the ice sheet in Greenland has behaved in the past era. It is vital if we want to know how it’ll behave in the near future.” The findings of the research are published in Earth and Planetary Science Letters.