Stories tagged Earth Structure and Processes
Gravitational compression
Will Earth ever freeze?: Internal radioactive decay is expected to keep Earth heated for billions of years.Courtesy NASA In its beginning, the Earth was so hot that it was entirely melted. That heat was generated because of gravitational compression. As gravity pulls materials in outer space towards each other they are compressed. When atoms and molecules are squeezed together they generate heat. Matter at the earth's center is very compressed; in fact, Earth is the densest planet in the Solar system.
Gravitational sorting
Penn State professor of geosciences, Chris Marone, feels that the original heat from that molten earth is only about 5 to 10 percent of the total heat within our planet. Another source of heat is from gravitational sorting.
In a gravitational sorting process called differentiation, the denser, heavier parts were drawn to the center, and the less dense areas were displaced outwards. The friction created by this process generated considerable heat, which, like the original heat, still has not fully dissipated.
Latent heat
Another source of heat is latent heat. When material in the center of the Earth changes from a liquid to a solid, heat is released. The solidified material also expands, which increases the pressure, thereby increasing the temperature. "The inner core is becoming larger by about a centimeter every thousand years," Marone says.
Almost all Earth's heat comes from radioactive decay
Marone says, the vast majority of the heat in Earth's interior—up to 90 percent—is fueled by the decaying of radioactive isotopes like Potassium 40, Uranium 238, 235, and Thorium 232 contained within the mantle. The amount of heat caused by this radiation is almost the same as the total heat measured leaving the Earth.
Source: Penn State University Live
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But what a way to go!: Look! I can see my house! Right on the center left, being sucked into an ultra dense, inescapable mass!Courtesy NASASo, what? You wanted to live forever?
Oh, you did? Er…even at the expense of scientific enterprise? Whatever. Deal with it, crybaby, because me and my little Strangelet are going to wring this planet dry.
Do you remember the Large Hadron Collider? No? We posted about it this spring on Science Buzz. It’s a recently completed supercollider in France and Switzerland—the largest supercollider in the world, with a 17-mile circumference. Protons will be blasted through the device so fast that they’ll make the entire circuit 11,000 times per second (which is about the speed of light, I believe). When two streams of protons meet, some of them will collide, and smash apart. At that point two huge detectors will attempt to gather data on just what comes out of the destroyed protons. The hope is that when the machine is switched on in August, we’ll make some fantastic discoveries about the most basic (and yet mysterious) elements of matter.
Oh, and the world might be instantly destroyed. I didn’t mention that last time? Huh. I suppose it just slipped my mind because, you know, who wants to live forever, right?
Some people (read: crybabies) are very concerned that the colliding particles could form a micro-black hole, which could either evaporate instantly, or gobble up the earth. Whoops! There’s some thought that the collider might also produce a spicy little devil we call the “strangelet.”
Stranglets are, it should be said, hypothetical—they’ve never actually been observed. A strangelet is basically a tiny piece of “strange matter,” stuff made up of the same components of regular vanilla matter, but in a unique configuration (equal amounts of up, down, and strange quarks, for those of you in to…quarks, I guess). The fear is that, where a strangelet to come into contact with regular matter on Earth, it could convert that matter into another strangelet, which would convert other matter into strangelets, until the whole of Earth would be turned into a big ball of hot strange matter. Which would just be the pits.
A particular group of people was so worried about the repercussions of turning on the LHC that they actually filed an injunction against its operators. The lawsuit was dismissed, on account of the defenders of humanity just “needing to chill out.”
The plaintiffs claimed that the odds of the LHC creating a global catastrophe are about one in fifty-million—about the same as winning the lottery, but that happens from time to time. Not to me, though.
The scientists behind the LHC, however, argue that the odds are much lower than that even, if not zero. Collisions like those planned for the LHC occur naturally every second, as cosmic rays smack into the earth, and so far everything is all right. Furthermore, should something like a micro-black hole be formed, mega-eggheads like Stephen Hawking predict that it would instantly turn to nothing.
And that’s kind of the thing—some of the world’s biggest smarty-pants are working on this project, and they aren’t concerned. That has to mean something, right? Then again, according to The Incredible Hulk, many scientists aren’t all that concerned about their own certain, imminent death, so long as they get to do some crazy experiments. And I trust comic books implicitly, so who knows.
Good lookin', bad soundin': Radiowaves that get caught up in the Northern Lights are creating some annoying noises that zap out into space.Courtesy NASANo wonder aliens want to attack the Earth with such regularity in the movies. From out in space, we sound pretty annoying, like that renter in the apartment above you who insists on playing Yoko Ono records at 2:30 in the morning.
You laugh, but new recordings from space show that Earth, our home, makes an array of nasty sounds that ring out across the universe.
Scientists have actually known about this phenomenon since the 1970s. But today we have some audio evidence of this annoying noise. So what’s happening?
There’s a bunch of radiation created high above our planet. Solar winds blow it into Earth’s magnetic field and then things start to get loud. Basically, this radiation gets sucked into the same conditions that cause the Northern Lights. While they look great, they sound horrible – sorta like Brittney Spears.
Earth’s ionosphere keeps the radio waves created in this action from coming down toward us, which is a good thing. That’s because they’re about 10,000 times stronger than any radio signals we have on our planet.
Satellites from the European Space Agency's Cluster mission, however, have now detected strong beams of these annoying radio waves out in space.
Click here to hear a sample of what this space noise sounds like. Personally, I think I’ve experienced this sound, much quieter, after eating a bad burrito.
Killer earthquake strikes Japan
Hundreds of troops armed with shovels and power-saws sifted through the splintered remains of a resort hotel in Japan Sunday in search of survivors after a powerful earthquake struck at around 8.45 a.m. on Saturday. (TurkishPress)
7.2 magnitude quake in Japan
Nine people were killed, 11 are missing, and more than 220 others were injured in the earthquake, the most powerful to strike inland Japan in eight years.
Read more by clicking the link below.
7.2 magnitude earthquake shakes Japan (TimesOnline)
Chinese earthquake locationCourtesy USGSThe Tangjiashan “quake lake”
formed by a landslide during China’s devastating May 12th earthquake is draining slowly thanks to a sluice constructed by engineers there. Fears of the lake bursting from its earthen dam pushed authorities to find a quick and effective way to release the pressure building from the backed-up water. More than a million people living in the area were under threat of being inundated with millions of cubic meters of water.
As work crews start construction of a second drainage channel, engineers are closely watching downstream riverbanks and bridges for any sign of stress from the surging waters.
The 7.9 magnitude earthquake killed over 60,000 people and more than 17,000 are still missing.
SOURCES AND LINKS
AP story
BBC report
Maps and photos of lake region
Here's mud on your truck: Here's a sample of mudder truck action. These photos are not from the May 3 event near Isanti, Minnesota, which has generated controversy about how much damage a private property owner can do to his own land.Courtesy katiewWhen does a mud hole turn into a wetland?
That’s a question that’s heated up debate in the north metro area as a rural Isanti man now faces wetland damage charges after hosting a mudder truck event on his property earlier this month.
The Minnesota Department of Natural Resources cited the guy under a little-used law for wetland damage. If convicted in court, he could be forced to restore the mud hole/wetland to its former condition, pay a big fine and/or serve jail time.
Chad Hunt, the property owner, contends he can do anything he’d like on his own property and that the area where the trucks were rumbling around on was just a mud hole. About a dozen modified trucks took part in the event on May 3, and also drew a large crowd of spectators.
The DNR took aerial photos of the site after the event (included in the news story link above) that show a large amount of truck ruts and damage.
So what do you think? How far do individual property rights extend when it comes to actions that could have negative environmental consequences? Where does a mud hole end and a wetland begin? What rights does a property owner forfeit when it comes to activities that take place on his property? Share your thoughts here with other Science Buzzers.
Earthquake in Sichuan, ChinaCourtesy U.S. Geological Survey
Toll from China quake estimated at 3,000 to 5,000
A 7.8-magnitude earthquake struck central China, but sent thousands of people rushing out of buildings and into the streets hundreds of miles away in Beijing and Shanghai.
The powerful earthquake trapped nearly 900 students in central China on Monday after their school collapsed and at least 107 people were killed across several provinces, state media reported.Yahoo News
New media allows instant news broadcasting
Blogs and a text message like tool called Twitter allowed the blogosphere to witness first person reports in real time (click examples below)
Are you just like JGordon? Do you feel smugly safe not living in earthquake-ridden California? Well, you may not be as safe as you think.
Midwest earthquake zoneCourtesy USGS via Wikimedia CommonsA powerful earthquake emanating from southern Illinois rattled skyscrapers in downtown Chicago this morning, and was felt as far away as Des Moines, Iowa, Atlanta, Georgia, and southern Ontario, Canada.
Folks in the region surrounding the quake's epicenter near the town of West Salem (map), in southeast Illinois, were rudely shaken out of bed at 4:37am CDT. Some places reported minor structural damage, such as bricks knocked from structures, and a collapsed porch.
The 5.2-magnitude quake (which coincidently has occurred on the very same day of the 1906 San Francisco earthquake) is thought to involve the Wabash Valley fault, an extension of the famous New Madrid fault in southern Missouri. Back in the early 1800s, the New Madrid fault was the source of one of the largest earthquakes felt in the contiguous United States (although at the time, the town of New Madrid, Missouri, for which the fault is named, was a part of the Louisiana Territory).
There will no doubt be more information about this current Midwest tremblor as the day goes on.
LINKS
New York Times story
USA Today
Doom and gloom from National Geographic
There's a 30% chance: That a strong earthquake will blow California 70 years back in time.Courtesy Nathan CallahanA recent comprehensive study has given the probabilities of major cities in California suffering an earthquake of 6.7 magnitude or greater in the next 30 years.
The “Uniform California Earthquake Rupture Forecast” predicts that, as a whole, there is a 99% chance that California will have a major earthquake sometime within the next 3 decades. As dramatic as this is, I’m not sure that it’s news. Show me a study that predicts California breaking off from the 48 before Christmas, and you got my interest, but this? Meh.
The UCERF does, however, give specific likelihoods for cities having big quakes, information which will be useful for policy makers determining earthquake insurance rates, local building codes, and emergency planning. The Los Angeles area, for instance, has a 67% chance of a 6.7 or greater quake in the next 30 years, and the SF Bay area has a 63% likelihood of such an incident.
As a point of reference, a 6.7 magnitude quake has the energy equivalent of 5,600,000 tons of dynamite exploding underground. The Northridge earthquake had a magnitude of 6.7, and it injured thousands of people, and caused 12.5 billion dollars in property damage to the L.A. area.
As a point of reference for the probabilities, there is approximately 65% chance that I will purchase a bag of generic brand frosted miniwheats sometime in the next three days. There’s a 99% chance that I will see a golden retriever in that time frame. It is 100% likely that I will stick my finger in my nose in the next 30 seconds… done. Now you know how that kind of thing works.
Goodness, gracious, here they come!: No reason to panic. Just think of them as giant parakeets that could swallow you whole.Courtesy Mark RyanNo, this isn’t about the herds of conventioneers descending upon the Saintly City for the Republican National Convention next fall. That would be disrespectful. I’m talking about the dinosaurs coming in June for five days at the Xcel Energy Center in a show called “Walking with Dinosaurs: The Live Experience“.
These aren't the same dinos that overran the Twin Cities last year during the Science Museum's 100th anniversary celebration. These latest dinosaurs are from Immersion Edutainment, an Australian company that uses a mix of computers, hydraulics, puppets, and actors to create a live show based on the highly acclaimed BBC television series by the same name.
And just in case you’re worried, these aren’t going to be cuddly and lame purple dinosaurs dancing about on ice, or jerky, hard-cased theme park animatronics, or even colorful plaster statues– no siree Bob – these are going to be scientifically accurate Mesozoic behemoths complete with life-like flexible skin, rippling muscles, swinging tails, snapping jaws, and heart-pounding sound-effects that will shake your popcorn right out of its box.
During the 90-minute show, a “paleontologist” serves as ringmaster and narrator, offering scientific insights into the world of these fantastic creatures. Geological concepts such as plate tectonics and continental drift help put things in perspective, as ten dinosaur species are presented in their proper order from the late Triassic to the late Cretaceous, including two enormous Brachiosaurs and everyone’s favorite, Tyrannosaurus rex. This is going to be one really BIG show!
Music and video projection will add to the dramatic content of the presentation and the program is deemed appropriate for all ages although some scenes could be a bit too intense for some very small kids.
Hoards of Australians evidently flocked to this thing when it toured sports arenas there. Performances here run June 11-15 at the Xcel Energy Center. And if 90 minutes of dinosaurs running amok aren’t enough for you, after the show, you can scoot across the street to the Science Museum and see the remains of some real dinosaurs. What could be better than that?
All the information you need about “Walking with Dinosaurs: The Live Experience” can be found at the Immersion Edutainment website.
