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| BENNYMARTY/ISTOCK VIA GETTY IMAGES |
Earth is roofed with Painfully
Ordinary geological structures, from volcanos to crystal-encrusted caves to
awe-inspiring canyons. While a variety of our planet’s mysteries are solved, a variety of its formations defy easy explanation. Here are a few of that also
baffle scientists.
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1- THE EYE OF THE SAHARA // MAURITANIA
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ISS CREW EARTH OBSERVATIONS FACILITY AND EARTH SCIENCE AND REMOTE SENSING UNIT, JOHNSON SPACE CENTER, NASA // PUBLIC DOMAIN
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The Eye of the Sahara, also mentioned
because the Richat Structure could also be a 28-mile-wide site of a giant
concentric circles found within the western African country of Mauritania.
Geologists initially thought the situation was created by an asteroid impact,
but there isn’t enough melted rock among the rings to support this theory.
Similarly, there’s no evidence to suggest an eruption. New Age enthusiasts hint
that the eye of the Sahara could represent the remains of the mythical sunken the island of Atlantis supported Plato’s allegory.
More recently, geologists have proposed
that the eye of the Sahara could be an eroded, collapsed geological dome,
formed some 100 million years ago when the supercontinent Pangea broke up.
Bolstering this theory are ancient rocks found on the surface, which originated
the utmost amount as 125 miles beneath the Earth’s crust and before life
existed on Earth. Research continues.
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2- LAKE HILLIER // AUSTRALIA
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KURIOZITETI123, WIKIMEDIA COMMONS // CC BY-SA 4.0
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This small, saltwater lake on an
island off Western Australia is simply one-third of a mile long, but its
bubblegum-pink color makes it especially striking. The lake was documented in
1802 by British explorer Flinders, who took a sample of its waters but didn't
understand how it got its startling hue. Tourists can visit only by helicopter,
though it's safe to swim within the waters.
Scientists today suspect the color is
because of the presence of a pink alga, Dunaliella salina, and/or a pink the bacterium, Salinibacter ruber. But unlike other pink lakes around the world,
like Lake Retba in Senegal, Lake Hillier’s color doesn’t fluctuate with
temperature or sunlight—so the investigation goes on.
3- the great UNCONFORMITY // us
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ALEX DEMAS, USGS // PUBLIC DOMAIN
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The Great Unconformity could also be
an enormous gap within the geological record: Layers of rock dating from about
1.2 billion to 250 million years ago are completely missing from certain areas
around the globe. This enormous chunk of lost time is often seen clearly
within the stratigraphy of the Grand Canyon in Arizona. Geologists studying the
anomaly there have noted that there is much rock, crammed with fossils, from
the Cambrian (540 million years ago) but the layer beneath its basement rock,
formed roughly 1 billion years ago and destitute of fossils. So, what happened
to the items in between?
An emerging theory—"Snowball
Earth”— may explain where the rock disappeared to. Around 700 million years
ago, Earth was encased in snow and ice. Moving glaciers peeled off the planet’s
crust with the help of lubricating sediments, pushing it into oceans, where it
had been reabsorbed by subducting tectonic plates. Many questions remain
unanswered, though—such because of the multimillion-year gap between the highest
of Snowball Earth, around 635 million years ago, and thus the beginning of the
Cambrian.
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4- NASTAPOKA ARC
// CANADA
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JEFF SCHMALTZ, MODIS LAND RAPID RESPONSE TEAM, NASA GSFC, WIKIMEDIA COMMONS // PUBLIC DOMAIN
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In the southeast corner of Hudson Bay
, Canada, lies a near-perfect arc. The mysterious half-circle, also mentioned
because the Hudson Bay Arc was first thought to be an impact crater from a
meteorite. But none of the quality confirming evidence, like shatter cones or
unusual melted rocks, has been found within the vicinity.
The most commonly accepted theory for
the arc supported geological evidence collected within the 1970s and later, is
that it is a boundary formed when one shelf of rock was pushed under another
other. That doesn’t explain how or why is it’s so perfectly round—so the
Nastapoka Arc remains subject to an ongoing study.
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5- MIMA MOUNDS // us
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ZRFPHOTO/ISTOCK VIA GETTY IMAGES
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The Mima Mounds are mysterious,
uniform undulations within the grasslands of Washington State near Olympia,
ranging from 10 to 164 feet in diameter and up to 6 .5 feet tall. When American
explorer Wilkes set eyes on them in 1841, he believed they were human-made
burial mounds and had three of them excavated, only to hunt out them full of
loose stones. Similar mounds are found from California to Colorado and have
puzzled naturalists for years.
Scientists suggest that a variety of the
mounds could even be 30,000 years old, which makes decoding them complex;
humans are believed to possess arrived in North America several thousand years
later than that. Many theories about their cause—glacial flooding, whirlpools,
and even wind-blown sediment clumping around vegetation—have been dismissed.
this leading theory, supported computer modeling, is that pocket gopher created the mounds. Yet doubts remain: nobody has ever witnessed a gopher
building one.
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6- FAIRY CIRCLES //
NAMIBIA
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DEMERZEL21/ISTOCK VIA GETTY IMAGES
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Up close, the fairy circles within The Namib Desert are just circular patches of bare red earth, surrounded by tufts
of grass. But from a bird’s-eye view, these spots stretch endlessly across the
arid landscape, creating a daily polka-dot pattern. Folktales claim the spots
are the gods’ footprints, but scientists have searched for an evidence-based
explanation.
At first, some proposed that the
circles are created when plants compete for water: the idea systems of the
successful vegetation dominate rock bottom, while smaller plants are unable to
compete, leaving bare patches of desert. In 2017, a promising new theory
appeared within the journal Nature. Excavations of several circles revealed
termite nests under all, implying the circles were created by the termites
eating the vegetation above their territory, allowing desert grasses to
flourish only between each nest. Ecologists modeled both the plant-competition
and hungry-termite theories, and located that both supported conditions
conducive to fairy circles. But with such a complicated ecosystem, scientists
say more research is required.
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7- YAMAL CRATERS //
RUSSIA
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JESSE ALLEN, EARTH OBSERVATORY, NASA // PUBLIC DOMAIN
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In 2014, a helicopter pilot flying
over the Yamal Peninsula in Siberia, which juts into the Kara Sea, noticed an
enormous hole within the permafrost. Scientists rushed to research the nearly
100-foot-wide crater and determine its origin. A meteorite impact, a gas
explosion, or alien interference were all floated as possible causes.
Tests of the air at the lowest of the
crater revealed very high levels of methane, pointing to an explosion—possibly
brought on by several unusually warm summers that destabilized the permafrost.
But an equally likely explanation, according to some researchers, is that the
crater represents a slow, long-term collapse of the permafrost itself rather
than a recent explosion. Since then, more craters are discovered. Further study
is required, but the treacherous permafrost makes research difficult.
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