Near the Markha River in Arctic Siberia, the Earth is rippling in ways scientists don’t fully understand.
Earlier this week, NASA researchers posted a series of satellite images of the peculiar wrinkled landscape on the agency’s Earth Observatory website. The photos, taken with the Landsat 8 satellite over several years, show the land on both sides of the Markha River, wavy with alternating dark and light stripes.
The enigmatic effect is visible in all four seasons, but most pronounced in winter, when white snow makes the contrasting pattern even stronger.
The striped swirls have perplexed scientists. (NASA Earth Observatory / Landsat 8)
Why is this particular part of Siberia so striped? Scientists aren’t entirely sure, and several experts offered NASA conflicting statements.
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One possible explanation is written in the icy ground. According to NASA, this area of the Central Siberian Plateau is covered with permafrost for about 9 percent of the year, although it thaws for short intervals every now and then.
Patches of land that continuously freeze, thaw, and refreeze are known to take on strange circular or striped designs called pattern soil, scientists reported in a study published in the journal in January 2003. ScienceThe effect occurs when soils and rocks sort themselves naturally during the freeze-thaw cycle.
The stripes of the Central Siberian Plateau vary seasonally. (NASA Earth Observatory)
However, other examples of patterned soil – such as the stone circles of Svalbard, Norway – are much smaller in scale 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 resemble a pattern in sedimentary rock known as layer cake geology.
These patterns occur when snow melt or rain trickles downhill, breaking down pieces of sedimentary rock in piles and washing away. The process can reveal slices of sediment that look like slices of a layer cake, Crafford said, with the darker streaks representing steeper areas and the lighter streaks representing flatter areas.
In accordance with the above image, these types of sedimentary layers would be more noticeable in winter, when white snow rests on the flatter areas, making them appear even lighter. The pattern fades as it approaches the river, where sediment collects after millions of years of erosion into more uniform piles along the banks, Crafford added.
This statement seems to fit well, according to NASA. But until the region can be studied up close, it will remain one of those quintessentially Siberian curiosities again.
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This article was originally published by Live Science. Read the original article here.