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Near the Markha river at Arctic Siberia, the earth ripples in a way that scientists do not fully understand.
Earlier this week, NASA researchers released a series of satellite images of the rippled landscape unique to the agency. Earth Observatory website. Taken with the Landsat 8 satellite for several years, the photos show the terrain on both sides of the Markha River rippling with alternating dark and light bands. The puzzling effect is visible in all four seasons, but it is more pronounced in winter, when the white snow makes the contrasting pattern even more striking.
Why is this particular section of Siberia so striped? Scientists are not entirely sure, and several experts have offered conflicting explanations to NASA.
Related: The 8 Greatest Mysteries on Earth
One possible explanation is written in the icy ground. This region of the central Siberian plateau spends about 90% of the year covered in permafrost, according to NASA, although it sometimes thaws for brief intervals. Patches of land that continually freeze, thaw and freeze are known to take on strange circular or striped patterns known as patterned soil, scientists reported in a study published in January 2003 in the journal Science. The effect occurs when soils and stones sort naturally during the freeze-thaw cycle.
However, other examples of patterned patterns – such as the stone circles from Svalbard, Norway – tend to be much smaller than the stripes seen in Siberia.
Another possible explanation is erosion. Thomas Crafford, a geologist with the US Geological Survey, told NASA that the stripes look like a pattern in sedimentary rocks known as layer cake geology.
These patterns occur when snowmelt or rain trickles down, chipping and throwing chunks of sedimentary rock into piles. The process can reveal patches of sediment that resemble slices of a layered cake, Crafford said, with the darker stripes representing steeper areas and the lighter stripes signifying flatter areas.
As per the image above, this type of sedimentary stratification would stand out more in winter, when white snow rests on the flattest areas, making them appear even lighter. The pattern fades as it approaches the river, where sediment collects in more even piles along the banks after millions of years of erosion, Crafford added.
This explanation seems to fit well, according to NASA. But until the area can be studied closely, it will remain another of those quintessentially Siberian sights.
Originally posted on Live Science.
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