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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.
1- THE EYE OF THE SAHARA // MAURITANIA
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 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 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.
2- LAKE HILLIER // AUSTRALIA
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
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.
4- NASTAPOKA ARC // CANADA
4- NASTAPOKA ARC // CANADA
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.
5- MIMA MOUNDS // us
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.
6- FAIRY CIRCLES // NAMIBIA
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.
7- YAMAL CRATERS // RUSSIA
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.
source: virallola
source: virallola
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