‘Stone Animal’ Lake Seen from Space in All Its Crimson Glory

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‘Stone Animal’ Lake Seen from Space in All Its Crimson Glory

  • 'Stone Animal' Lake Seen from Space in All Its Crimson Glory
The crimson glow in Tanzania’s Lake Natron, shown here in an image captured from the Landsat 8 satellite on Marck 6, 2017, is caused by salt-loving microbes called haloarchaea.

Credit: NASA Earth Observatory

One of the world’s weirdest lakes stands out in scarlet in new NASA images.

Lake Natron in northern Tanzania is an incredibly alkaline body of water. Its pH is as high as 10.5 — not quite as caustic as ammonia, but similar to the laxative Milk of Magnesia. The reason for this bizarre chemistry is the volcanic geology surrounding Lake Natron. The minerals and salts produced by volcanic processes — particularly sodium carbonate — push Lake Natron’s water far above water’s typical pH of around 7, which is neutral on the 0 to 14 pH scale.

Image Album: Lake Natron Gives Up Its Dead

Many animals can’t survive in water that alkaline, but the lake is home to flocks of flamingos and other birds as well as tilapia fish. When the lake’s animals die, their bodies are sometimes preserved by the sodium carbonate minerals that are responsible for the water’s strange chemistry. Ancient Egyptians used sodium carbonate and other naturally occurring salts, known as natron, in their mummification practices. [Photos: Lake Natron Gives Up Its Dead]

Image Album: Lake Natron Gives Up Its Dead

On March 6, 2017, NASA’s Landsat 8 satellite swooped over Lake Natron and snapped shots of the water’s vermillion beauty. The red color is due to haloarchaea, microorganisms that thrive in the lake’s salty waters,according to NASA’s Earth Observatory. At the end of the dry season, when this image was taken, the lake level is particularly low and the concentrated salt ponds are especially colorful.

Lake Natron, located in the Rift Valley of Tanzania, spans an area of about 480 square miles (1,250 square kilometers), according to the World Wildlife Fund.

Lake Natron, located in the Rift Valley of Tanzania, spans an area of about 480 square miles (1,250 square kilometers), according to the World Wildlife Fund.

Credit: NASA Earth Observatory

Near Lake Natron sits Ol Doinyo Lengai, an active volcano that rises abruptly out of the surrounding arid grasslands. According to the Smithsonian Institution’s Global Volcanism Program, Ol Doinyo Lengai is the only volcano that has erupted carbonatite lava in human history. Unlike most volcanos, which spit out glassy, silica-rich lava, carbonatite lava contains very little silica. It’s made, instead, of carbonate minerals (like natron) that are more commonly seen in sedimentary rocks.

Ol Doinyo Lengai’s carbonatite lava is especially bizarre, erupting at temperatures of around 930 degrees Fahrenheit to 1,100 degrees Fahrenheit (500 to 600 degrees Celsius), according to the Hawaiian Volcano Observatory. Silica-rich Kilauea lava clocks in at 2,120 degrees F (1,160 degrees C), for comparison, while Mount St. Helens spews lava reaching 1,472 degrees F (800 degrees C).

Original article on Live Science.


Top 10 Rocks That Stink

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Top 10 Rocks That Stink


When people think about the properties of rocks, odor is not one of the things that comes to mind. Rocks and minerals aren’t known for what they smell like. Most handbooks and manuals of mineralogy make no mention of odor. In general, it’s true that most rocks don’t smell, but there are some that do.




Photo credit: Didier Descouens

Antozonite is a variety of the mineral fluorite with color that shades from dark violet to black. It’s not unusual for a mineral to have a nickname, but antozonite has several. In German, it is known as “stink-fluss” and “stink-spat.” In English, it has earned the names “stinkspar” and “fetid fluorite.” This rare form of fluorite is infamous for its smell.

When antozonite breaks or is crushed, it reeks. The source of the stench isfluorine gas trapped inside the tiny, porous spaces inside the mineral. When those pores are broken open, the acrid fluorine gas is released and reacts with oxygen and hydrogen in the air. The result of the reactions is pungent ozone gas and hydrofluoric acid vapor, which will attack any unsuspecting noses nearby. Fetid fluorite lives up to its name.



Photo credit: Nevada Outback Gems

Sphalerite is the scratch-and-sniff mineral. It is made up of the elements iron, zinc, and sulfur. It’s also the most important ore mineral for zinc. Sphalerite is commonly found around mineral-rich areas known as sulfide deposits. While it can form lovely transparent yellow-brown to black crystals, it often occurs as an ugly, dark lump with yellow, red, brown or black tints. Unfortunately, there are many other minerals that can also look like dark, ugly lumps with tints of various colors.

Because the color of sphalerite can be so different from place to place, almost every student who has ever taken a mineralogy class has learned a quick and easy scratch-and-sniff test to identify sphalerite: Use the mineral to scratch a piece of unglazed porcelain (called a streak plate), and immediately sniff the scratched mineral. The streak on the porcelain will be a shade of yellow, and the scratched mineral will have a sulfur-like smell resembling the odor of a just-lit match.



Jet Jewelry

Photo credit: Detlef Thomas

The poorest grade of coal is lignite. Living up to its identity as a fossil fuel, many pieces of lignite are true fossils that preserve the shape of trees and branches. The 19th-century Victorians liked to carve and polish lignite to a mirror finish and use it in jewelry. They named it jet. The best-known location for jet is the seaside town of Whitby, on England’s northeastern coast.

Queen Victoria made Whitby famous. After the death of her husband, Prince Albert, Victoria dressed in mourning black for the rest of her life. She popularized jet jewelry from Whitby because jet was one of the few gemstones that didn’t clash with her all-black wardrobe. This makes jet the only fossil fuel that doubles as a fashion accessory.

One of the tests used to identify jet is to heat a needle and then stick it into the rock. If the rock is jet, it will smell like burning tar or coal. Black plastic will smell like burning plastic, and black gemstones like onyx and hematite will not smell at all after being poked with a hot needle. The hot needle test will leave a little pit on the surface of the jet, so it’s not a good idea to try this on your grandmother’s antique Victorian brooch.



Photo credit: Mauro Cateb

Many sulfide minerals are known for their sulfur-like stink. Pyrite, famously known as “fool’s gold,” is the shiny, gold-colored mineral often mistaken for gold. There is no gold in pyrite, only iron and sulfur. Unfortunately for amateur prospectors, pyrite and gold are often found in the same places. There are several ways to tell pyrite from gold, and one is with your nose.

When gold is warmed up, it has no smell, but when pyrite is warmed up, the mineral will begin to stink. Warmed pyrite releases sulfur into the air. That sulfur vapor wants to bond with oxygen and hydrogen in the atmosphere, producing hydrogen sulfide and sulfur dioxide. Hydrogen sulfide (HS) is responsible for the smell of rotten eggs. Sulfur dioxide (SO2) is the smell of brimstone, the poetic name for burning sulfur. Hot fool’s gold: It stinks!



Photo credit: J.J. Harrison

Not all of the smelly sulfide minerals smell like sulfur. There is one mineral that is shiny like pyrite and also contains sulfur and iron like pyrite (plus one other element), but when struck with a hammer or scratched with unglazed porcelain, it smells like garlic! Even if you love garlic in your food, don’t go taking deep whiffs of this mineral because that one other element is arsenic. This mineral is called arsenopyrite, a pale yellow pyrite lookalike.

The garlic smell is actually the smell of arsenic trihydride, better known as arsine gas. The toxic gas released from scratching or striking a small piece of arsenopyrite isn’t enough to poison an adult, but arsenopyrite isn’t a mineral anyone wants to leave on a kitchen windowsill or in the centerpiece on the dining room table. It may be pretty, but you don’t want children and pets to get a hold of it.




Photo credit:

Anthraconite is a black limestone made of calcite and bitumen. It is also known as “stinkstone” or “swinestone.” Bitumen is that black, sticky tar that is mixed with sand and pebbles to make asphalt road surfaces, though some people use the word “asphalt” interchangeably with “bitumen.” In North America, many people use the word “asphalt” for both the tar substance and the road surface, while many people in Australia use the word “bitumen” in the same way. Regardless, anthraconite is full of bitumen.

If you rub anthraconite with a rag or heat it up, it lives up to its name and produces a fetid or tarry stench. Thankfully, it is an uncommon rock; there are only a few places with notable outcrops, like Michigan and Ontario in North America and Saxony-Anhalt in Germany.


Amber Jewelry

Photo credit: Wikimedia

Another organic gemstone that also has its own smell is amber. Like Whitby jet, amber is also a fossil. In this case, it’s fossilized free resin that is millions of year old. Amber isn’t black and opaque like jet. Instead, it is a clear, yellow-to-red stone, famous for washing up on beaches along the Baltic Sea. It is often less dense than saltwater, so it can float on the surface of ocean. Deposits of amber exist all over the world, and people find or dig for amber in places like Alaska, Prussia, Latvia, New Jersey, Kansas, and the Dominican Republic.

Like jet, the smell of amber is liberated using the hot needle test: Heat a needle up and sick it into the amber. The resultant smell is like burning pine sap or woody incense but with more smoke in it. The hot needle test will leave a pit in the amber, too.

The burning pine smell from amber is not the scent marketed by the perfume industry as “amber scent” or “essential oil of amber.” The use of the word “amber” in perfumes is unrelated to the actual gemstone. Perfume amber is based on modern wood oils and has nothing to do with rocks.

3Oil Shale

Oil Shale

Photo credit: Amcyrus2012

Shale is a clay-rich sedimentary rock found all over the world. If shale gets wet, it usually smells like mud or wet dirt. However, the rock known as oil shale has a smell like diesel oil or tar. That oily smell is from a petroleum-like substance known as kerogen. Kerogen is not yet oil. It needs to be heated or treated with solvents first to turn it into oil.

Getting the oil out of oil shale is not easy, as shale is good at preventing the flow of fluids like water and oil. Even if the kerogen could be turned into oil within the shale, pumping it out is expensive and difficult to do without harming groundwater or the environment. Some oil shale could be mined and then treated above the ground, but mining is expensive and, again, not friendly to the environment.

It will be a long time before anyone uses oil shale to produce oil. Regardless, it’s not hard to find an outcrop of oil shale in areas where it is common, like Northwestern Colorado in North America or coastal Queensland in Australia. On a warm day with no wind, just follow your nose.


No list of rocks that stink can omit the smelly rock made famous by the Bible itself: brimstone. The first famous mention of brimstone in the Bible comes from the Book of Genesis, Chapter 19, Verse 24: “Then the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven.” Equally as famous is the lake of fire and brimstone from Chapter 21, verse 8 in the Apocalypse of Saint John, better known as the Book of Revelation: “The fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone.”

“Brimstone” is an old name for sulfur, from the Old English “brynstan,” which means “burning rock.” Sulfur and fire are often found together at volcanoes. Volcanic gasses can deposit sulfur on the surfaces of volcanoes and around the mouths of volcanic steam vents called fumaroles. Sulfur is quite flammable, so volcanic eruptions will usually set any sulfur deposits that are present on fire. Fire and brimstone really do go together in nature. Pure, elemental sulfur has no smell. It is the sulfur dioxide smell produced byburning sulfur that is associated with fire and brimstone.



Photo credit: GOKLuLe

Kaolinite is the mineral name for China clay. It is a beautiful, white clay named after Kao-Ling Mountain in China. It is used to make all kinds of ceramics and is also safe to eat. While eating clay may sound strange, people have been swallowing kaolinite for years. It is used in medicines as well as toothpastes.

Up until the late 1980s, the anti-diarrhea drug Kaopectate had two active ingredients: kaolinite and pectin. The odorless sugar compound pectin is a soluble fiber and thickening agent used to make jellies and jams, while kaolinite is excellent at absorbing fluids. The combination of the two was effective against the runs. People old enough to remember the original Kaopectate may also remember its distinctly chalky, clayey smell. That is the smell of the mineral kaolinite.

Catherine Clark is a retired scientist and former college instructor of mineralogy. She writes a blog with the self-explanatory title of

These 208 Minerals Exist Solely Due to Humans

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These 208 Minerals Exist Solely Due to Humans

Plate Tectonics and Continental Drift (Infographic)

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Plate Tectonics and Continental Drift (Infographic)


A Dramatic 260 Foot Crater Has Mysteriously Appeared In Siberia

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A Dramatic 260 Foot Crater Has Mysteriously Appeared In Siberia

7/16/14 3:32pm

Russian geologists are on their way to a remote region of Siberia’s Yamal Peninsula to investigate the mysterious appearance of what looks like a gigantic Sarlac Pit. Opinions are divided as to what caused the apparent crater.

As the Siberian Times is reporting, the unexplained hole was spotted by a helicopter flying over the gas-rich region of the Yamal peninsula, a location that translates to the “end of the world.” Initial estimates place the width of the puncture at about 80 meters, but its depth is not known. A debris field around the perimeter suggests that the material was somehow thrown out of the crater.

An expedition to the crater has been organised by the Yamal authorities. The team includes two experts from the Centre for the Study of the Arctic and one from Cryosphere Institute of the Russian Academy of Sciences. They’re expected to arrive at the scene later today, at which time they’ll take samples of soil, air, and water.

According to the Siberian Times, initial reports and images were suspected to be fakes, but the new images taken by Russian engineer Konstantin Nikolaev suggests it’s very much real. The feature is thought to have formed about two years ago.

Scientist have posited a number of theories to explain the crater, though it’s not likely to have been caused by a meteorite impact, nor does it exhibit the features of a sinkhole. One website claims that it’s evidence “of the arrival of a UFO craft” to Earth. But there are at least two other — and far more plausible — explanations worth considering.

A Pingo

University of New South Wales polar scientist Chris Fogwill says it’s probably a geological phenomenon known as a collapsed pingo, or hydrolaccolith. As theSydney Morning Herald reports, a pingo is a block of ice that’s grown into a small hill in the frozen arctic ground:

The ice can eventually push through the earth and when it melts away it leaves an exposed crater. Dr Fogwill says the permafrost [frozen earth] can be hundreds of metres thick, allowing for large ice features.

“It’s just a remarkable land form.

“This is obviously a very extreme version of that, and if there’s been any interaction with the gas in the area, that is a question that could only be answered by going there,” Dr Fogwill said.

Fogwill says that global warming may cause more pingos in the future.

An Ignited Mixture

Another explanation has been posited by Anna Kurchatova from Russia’s Sub-Arctic Scientific Research Center. She believes the crater was formed by a water, salt, and gas mixture that ignited an underground explosion, also the result of global warming.

Kurchatova thinks that enough gas accumulated in ice mixed with sand beneath the surface, and that this was mixed with salt. And indeed, this area was immersed under the sea some 10,000 years ago. The change in climate caused an “alarming” melt in the permafrost, releasing gas akin to the popping of a champagne bottle cork.

Given that this region contains many gas pipelines, that’s a troubling conclusion.

Read more at the Siberian Times and the Sydney Morning Herald.

All images: Konstantin Nikolaev via Siberian Times

Follow me on Twitter: @dvorsky

Every US River Visualized in One Glorious Map

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Every US River Visualized in One Glorious Map

The Deadliest Volcano in the United States Just Got Really Weird

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The Deadliest Volcano in the United States Just Got Really Weird

A plume of steam and ash billowing out of Mt. Saint Helens in 1982, two years after the most destructive eruption in US history. Image: Wikimedia

Picture a volcanic eruption: fiery magma and smoke billowing skyward as a towering mountain empties its over-pressurized belly of a hot meal. At least, that’s how most of us think it works. So you can imagine volcanologists’ surprise when they discovered that Mount St. Helens, which was responsible for the deadliest eruption in US history, is actually cold inside.

Apparently, it’s stealing its fire from somewhere else.

Mount St. Helens is one of the most active volcanoes of the Cascade Arc, a string of eruptive mountains that runs parallel to the Cascadia subduction zone from northern California to British Columbia. It’s also one of the strangest. Most major volcanoes of the Cascade Arc sit neatly along a north-south line, where the wedging of the Juan de Fuca tectonic plate beneath the North American plate forces hot mantle material to rise. Mount St. Helens, however, lies to the west, in a geologically quiescent region called the forearc wedge.

“We don’t have a good explanation for why that’s the case,” said Steve Hansen, a geoscientist at the University of New Mexico in Albuquerque.

Image: US Geological Survey

Seeking answers, Hansen recently led a seismic mapping survey of Mount St. Helens. In the summer of 2014, his team deployed thousands of sensors to measure motion in the ground around the volcano. Then, they drilled nearly two dozen holes, packed the holes full of explosives, triggered a handful of minor quakes, and watched as seismic waves bounced around beneath the mountain. “We’re looking at what seismic energy propagates off in the subsurface,” Hansen explained. “It’s a bit like a CAT scan.”

Their analysis, which is published today in Nature Communications, appears to have created more questions than it answered. From seismic reflections, Hansen and his colleagues learned that the types of minerals present at the boundary between Earth’s crust and mantle are markedly different to the east and west of Mount St. Helens, confirming that this area is geologically special. But instead of finding a hot magma chamber directly beneath the volcano, seismic data indicates a relatively cool wedge of serpentine rock.

Not only is Mount St. Helens out of place, but it also lacks the magma reserves we’d expect given its violent history. So, where on Earth is Mount St. Helens getting its fuel?

Hansen suspects the volcano’s magma source lies to the east, closer to the rest of the Cascade Arc, where material in the upper mantle is hotter. But that still leaves the question of why gooey rock being forced westward, through the crust or upper mantle, to erupt in this one off-kilter location. Earthquakes in the deep crust may be partially responsible, but more data is needed to confirm such a link.

Fortunately, more data is exactly what Hansen, and other scientists associated with the Imaging Magma Under St Helens (iMUSH) project, are now collecting. What geologists learn about this weird volcano—how its magmas form, how they moved around, when and why they erupt—could improve our understanding of volcanic arc systems around the world.

“Mount St. Helens is pretty unusual,” Hansen said. “It’s telling us something about how the arc system is behaving, and we don’t yet know what that something is.”

[Nature Communications]

Maddie is a staff writer at Gizmodo