Man-Mediated Minerals

“Robert Hazen, a mineralogist at the Carnegie Institution for Science, and his colleagues tallied up the number of minerals on Earth only to discover that a large number have been created, thanks to human activities. Although minerals, by definition, must form via natural processes, Hazen’s team discovered 208 minerals mediated by humans—they did form naturally but in places such as man-made mines, where unnatural humidity or fires from mining operations created new minerals along the mine walls. Other examples might be even harder to find, unless you are a deep-sea diver; when bronze or brass artifacts sink in a shipwreck, for example, they interact with the seafloor to create novel, man-mediated minerals.

“Perhaps more striking are mineral-like compounds—substances that would be characterized as minerals if they were not completely man-made (rather than human-mediated). Hazen’s team created a long list of these as well—everything from synthetic rubies and diamonds to ceramics, brick, cement, batteries and certain components of cell phones—and they suspect there are hundreds of thousands of varieties, too many for them to count.

“Such dramatic changes will not go unnoticed if a future geologist finds herself digging up layers of sediment from an ancient city. “These are the real global marker of our age,” Hazen says. Not only because a city’s infrastructure contains many of these man-made minerals but because it also contains natural minerals that were quarried in locations across the world, creating concentrations that would not be found naturally. Even if sea levels rise 300 feet and cover coastal cities, those minerals will still be visible in the sedimentary record. That’s because landmarks like the Washington Monument and the Smithsonian will collapse into piles of rubble—signatures that are later preserved as highly unusual lens-shaped pockets underground, distinct from their surroundings in both shape and minerals. The Washington Monument, for example, will eventually be a lens-shaped pocket composed of limestone where no other limestone is found. And the pocket that was once the Smithsonian will contain so many rare minerals that they could not possibly have formed so close together in nature. To boot, they will be surrounded by the vast array of the man-made minerals we use every day. “There is nothing at all like this in the geology of the past 4.5 billion years on Earth,” Zalasiewicz says. “It is tragically different.”

Text: Shannon Hall, Found: Thousands of Man-Made Minerals—Another Argument for the Anthropocene, Scientific American.

Pic: “Fordite, also known as Detroit agate or Motor Agate, is old automobile paint which has hardened sufficiently to be cut and polished. It was formed from the buildup of layers of enamel paint slag on tracks and skids on which cars were hand spray-painted (a now automated process), which have been baked numerous times.” – Wikipedia

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“Where is this information?”

“Millions of years ago, a few spiders abandoned the kind of round webs that the word “spiderweb” calls to mind and started to focus on a new strategy. Before, they would wait for prey to become ensnared in their webs and then walk out to retrieve it. Then they began building horizontal nets to use as a fishing platform. Now their modern descendants, the cobweb spiders, dangle sticky threads below, wait until insects walk by and get snagged, and reel their unlucky victims in.

“In 2008, the researcher Hilton Japyassú prompted 12 species of orb spiders collected from all over Brazil to go through this transition again. He waited until the spiders wove an ordinary web. Then he snipped its threads so that the silk drooped to where crickets wandered below. When a cricket got hooked, not all the orb spiders could fully pull it up, as a cobweb spider does. But some could, and all at least began to reel it in with their two front legs.

“Their ability to recapitulate the ancient spiders’ innovation got Japyassú, a biologist at the Federal University of Bahia in Brazil, thinking. When the spider was confronted with a problem to solve that it might not have seen before, how did it figure out what to do? “Where is this information?” he said. “Where is it? Is it in her head, or does this information emerge during the interaction with the altered web?”

“In February, Japyassú and Kevin Laland, an evolutionary biologist at the University of Saint Andrews, proposed a bold answer to the question. They argued in a review paper, published in the journal Animal Cognition, that a spider’s web is at least an adjustable part of its sensory apparatus, and at most an extension of the spider’s cognitive system.

“This would make the web a model example of extended cognition, an idea first proposed by the philosophers Andy Clark and David Chalmers in 1998 to apply to human thought. In accounts of extended cognition, processes like checking a grocery list or rearranging Scrabble tiles in a tray are close enough to memory-retrieval or problem-solving tasks that happen entirely inside the brain that proponents argue they are actually part of a single, larger, “extended” mind.”

Text: The Thoughts of a Spiderweb, Quanta Magazine.

Pic: Odilon Redon, The Smiling Spider, 1891.

Crash the World Economy

 

“The asteroid, called 16 Psyche, is a massive hunk of precious metals including platinum and gold as well as iron and nickel.It orbits the sun between Mars and Jupiter and is of great scientific interest because it holds clues to one of the earliest eras in the history of our solar system — less than 10 million years after the birth of our sun.

“But now it’s grabbed the attention of money-hungry entrepreneurs and investors thanks to its stratospheric price tag. Valued at $A14,000 quadrillion, according to Lindy Elkins-Tanton, the lead scientist on the NASA mission, it is definitely worth more than its weight in gold.

“But bringing back an asteroid of this value could completely wipe out our global economy. Luckily, the space agency is taking the trip for scientific purposes and isn’t planning on conducting any mining — yet.”

Text: Magi Murphy, NASA announces 2022 mission to explore metal asteroid so valuable it could crash the world economy

‘Under the stars,’ she repeated. ‘I never noticed the stars before. I always thought of them as great big diamonds that belonged to someone. Now they frighten me. They make me feel that it was all a dream, all my youth.’

‘It was a dream,’ said John quietly. ‘Everybody’s youth is a dream, a form of chemical madness.’

How pleasant then to be insane!’

So I’m told,’ said John gloomily. ‘I don’t know any longer. At any rate, let us love for a while, for a year or so, you and me. That’s a form of divine drunkenness that we can all try. There are only diamonds in the whole world, diamonds and perhaps the shabby gift of disillusion. Well, I have that last and I will make the usual nothing of it.”

Text: F. Scott Fitzgerald, The Diamond as Big as the Ritz

Black-eyed Angels

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I jumped in the river, what did I see?
Black-eyed angels swam with me
A moon full of stars and astral cars
And all the figures I used to see

All my lovers were there with me
All my past and futures
And we all went to heaven in a little row boat
There was nothing to fear and nothing to doubt

Text: Pyramid Song, Radiohead.

Image: What the world would look like if all the ice melted, National Geographic.

Snakes & Trains

Gefter: But how can seeing a false reality be beneficial to an organism’s survival?

Hoffman: There’s a metaphor that’s only been available to us in the past 30 or 40 years, and that’s the desktop interface. Suppose there’s a blue rectangular icon on the lower right corner of your computer’s desktop — does that mean that the file itself is blue and rectangular and lives in the lower right corner of your computer? Of course not. But those are the only things that can be asserted about anything on the desktop — it has color, position, and shape. Those are the only categories available to you, and yet none of them are true about the file itself or anything in the computer. They couldn’t possibly be true. That’s an interesting thing. You could not form a true description of the innards of the computer if your entire view of reality was confined to the desktop. And yet the desktop is useful. That blue rectangular icon guides my behavior, and it hides a complex reality that I don’t need to know. That’s the key idea. Evolution has shaped us with perceptions that allow us to survive. They guide adaptive behaviors. But part of that involves hiding from us the stuff we don’t need to know. And that’s pretty much all of reality, whatever reality might be. If you had to spend all that time figuring it out, the tiger would eat you.

Gefter: So everything we see is one big illusion?

Hoffman: We’ve been shaped to have perceptions that keep us alive, so we have to take them seriously. If I see something that I think of as a snake, I don’t pick it up. If I see a train, I don’t step in front of it. I’ve evolved these symbols to keep me alive, so I have to take them seriously. But it’s a logical flaw to think that if we have to take it seriously, we also have to take it literally.

Gefter: If snakes aren’t snakes and trains aren’t trains, what are they?

Hoffman: Snakes and trains, like the particles of physics, have no objective, observer-independent features. The snake I see is a description created by my sensory system to inform me of the fitness consequences of my actions. Evolution shapes acceptable solutions, not optimal ones. A snake is an acceptable solution to the problem of telling me how to act in a situation. My snakes and trains are my mental representations; your snakes and trains are your mental representations.

Text: Amanda Geftner, The Case Against Reality, The Atlantic. 

Image: Huang Yong Ping, Ressort 2012

Bizarre Features

The-Great-Wave-off-Kanagawa-by-Hokusai-coloring-page

“According to the team’s modeling, the waves near the point where the asteroid struck would have been approximately 300 metres tall. When they hit the coast they wouldn’t be quite that big, but would still have reached 75 or 80 metres, Costard says.

“The most probable source of the tsunami, the scientists concluded, is a 60-kilometre impact crater located about 1000 kilometres off the putative coast. But it is also possible that the deposits could have been produced by the combined results of two independent impacts, represented by smaller craters closer to the shore.

“The new research also explains bizarre features known as thumbprint terrain, on the seaward ends of some of the tsunami deposits. Composed of curving, concentric ridges 10 to 20 metres high, these look for all the world like the ridges in a fingerprint.

“The explanation, Clifford says, starts with the fact that the tsunami would have come in two pulses. The first would have been produced when the asteroid hit, shoving tremendous amounts of water out of its way. The second would have occurred when water rushed back into the resulting depression from all sides.

“The onrushing water would have crashed together in the centre of the impact depression in a giant splash, then rebounded outward in a second tsunami, even larger than the first.

“And that’s just the beginning of the story. When the first wave, a few minutes ahead of the second, hit the shoreline, part of it would have been reflected back out to sea. There, it would have met the oncoming second wave, where the turbulence would have caused sediment to be dropped in patterns exactly like the enigmatic thumbprint terrains.”

Text: Mars may have experienced a giant tsunamiCosmos Magazine.

Image: The Great Wave Off Kanagawa By Hokusai, Supercoloring version.

A Hole in the Atmosphere

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“Obviously, something […] big hitting the Earth is going to hit with a lot of energy. […] This is the energy one million tons of dynamite would release if it was exploded and is the energy unit used for nuclear explosions. The largest yield of a thermonuclear warhead is around 50–100 megatons. The kinetic energy of the falling object is converted to the explosion when it hits. The 10-kilometer object produces an explosion of 6 × 107 megatons of TNT (equivalent to an earthquake of magnitude 12.4 on the Richter scale). The 1-kilometer object produces a milder explosion of “only” 6 × 104 megatons (equivalent to an earthquake of magnitude 9.4 on the Richter scale).

“On its way to the impact, the asteroid pushes aside the air in front of it creating a hole in the atmosphere. The atmosphere above the impact site is removed for several tens of seconds. Before the surrounding air can rush back in to fill the gap, material from the impact: vaporized asteroid, crustal material, and ocean water (if it lands in the ocean), escapes through the hole and follows a ballistic flight back down. Within two minutes after impact, about 105 cubic kilometers of ejecta (1013 tons) is lofted to about 100 kilometers. If the asteroid hits the ocean, the surrounding water returning over the the hot crater floor is vaporized (a large enough impact will break through to the hot lithosphere and maybe the even hotter asthenosphere), sending more water vapor into the air as well as causing huge steam explosions that greatly compound the effect of the initial impact explosion.

“There will be a crater regardless of where it lands. The diameter of the crater in kilometers is = 0.765 × (energy of impact in megatons TNT). Plugging in the typical impact values, you get a 150-kilometer diameter crater for the 10-kilometer asteroid and a 20-kilometer diameter crater for the 1-kilometer asteroid. The initial blast would also produce shifting of the crust along fault lines.

The oceans cover about 75% of the Earth’s surface, so it is likely the asteroid will hit an ocean. The amount of water in the ocean is nowhere near large enough to “cushion” the asteroid. The asteroid will push the water aside and hit the ocean floor to create a large crater. The water pushed aside will form a huge tidal wave, a tsunami. […] What this means is that a 10-km asteroid hitting any deep point in the Pacific (the largest ocean) produces a megatsunami along the entire Pacific Rim.

“Some values for the height of the tsunami at different distances from the impact site are given in the following table. The heights are given for the two typical asteroids, a 10-kilometer and a 1-kilometer asteroid.

Distance (in km) 10 km asteroid 1 km asteroid
300 1.3 km 42 m
1000 540 m 18 m
3000 250 m 8 m
10000 100 m 3 m

“The steam blasts from the water at the crater site rushing back over the hot crater floor will also produce tsunamis following the initial impact tsunami and crustal shifting as a result of the initial impact would produce other tsunamis—a complex train of tsunamis would be created from the initial impact (something not usually shown in disaster movies).”

Text: Nick Strobel, Effects of an Asteroid Impact on Earth, Astronomynotes.com

Image: “The Chelyabinsk event of 15 Feb. 2013, having an energy equivalent to 500 kilotons of TNT, was the largest well-documented meteor event since the Tunguska event of 1908. Analysis of the Chelyabinsk object’s in-atmosphere trajectory from video records has found that its orbit was similar to the orbit of the 2-km-diameter Near-Earth Asteroid 86039 (1999 NC43).There is a possibility that the Chelyabinsk object was created through a collision between asteroid 86039 and another asteroid. It is also very interesting that the Cheyabinsk Asteroid approached from the Sun’s direction, making it essentially undetectable in telescopes” – Analysis of Chelyabinsk meteor and resultant air burst appears in Nature