According to New Scientist:

The magma inside the volcano did not reach the surface and erupt as a fountain of lava – instead, it was diverted into the continental rift underground. The magma cooled into a wedge-shaped "dike" that was then uplifted, rupturing the surface and creating a 500-metre-long, 60-metre-deep crack . . . Eventually it could reach the east coast of Ethiopia and fill up with seawater. "At some point, if that spreading and rifting continues, then that area will be flooded," says Ken Macdonald, a marine geophysicist at the University of California, Santa Barbara, who was not involved with the study.

Ebinger says this won't happen any time soon – it would take around 4 million years for the crack to reach the size of the Red Sea.

[via New Scientist]

This photo was taken by Carsten Peter for National Geographic. The magazine explains:

[In the Afar Depression,] spreading mid-ocean ridges forming the Red Sea and the Gulf of Aden emerge on land and meet the East African Rift.

Those circular structures around the pool are made of travertine, which is "a volcanically heated, calcium-rich flow from hot springs." Want to see a bigger version of this photo, plus several more images of what happens to the land at the edges of tectonic plates? Check out the photo essay at National Geographic.

Thanks, Marilyn Terrell!

Located in Montana and Wyoming, Yellowstone is famous for its geysers, including "Old Faithful," which blasts steam into the air like clockwork every day. Now geologists studying the recent mini-quakes in the park say we might be in for a big blast. Such blasts tend to come about once every 600 thousand years, and we haven't seen one for roughly that amount of time.

The last big explosion in Yellowstone, according to Scientific American, was roughly 640 thousand years ago, and it covered about 240 cubic miles in hot ash, scalding rocks, and magma. But don't worry yet, says SciAm's David Biello:

Although the earthquake swarm continues, according to the Yellowstone Volcano Observatory, the volcano alert level remains normal. And a slew of larger earthquakes have occurred throughout the western U.S., Alaska, Puerto Rico and even Pennsylvania in the past week without incident, according to the U.S. Geological Survey.

In recent years, Yellowstone's caldera has been rising thanks to uplifting magma beneath it—leading to more cracks, hot springs and even more frequent eruptions of Steamboat Geysers. Paired with the earthquakes, such magma movement might presage an eruption—either big or small. Unfortunately, scientists can't really predict when the next such eruption will happen, and the range of possibilities is large: from later today to a million years from now.

How will we know if we should start worrying? The real warning signs will be rapid changes in the shape of the ground as well as volcanic gases leaking from the ground, neither of which have been sighted—yet.

Right now, in some dark Hollywood pitch meeting, Jerry Bruckheimer is mud-wrestling with Michael Bay over the rights to a movie about this potential explodey Yellowstone disaster.

SOURCE: Scientific American

Thanks, Robert Atlas!

Photo by Nina Raingold/Getty Images.

Listen to that sound. I want Meshuggah or Arch Enemy to sample that one and scream over it about industrial death. Over at Discover, io9 pal Michael Reilly describes this second video:

Several kilometers of ice shearing off the Greenland ice sheet is always awesome to behold, and the few thousand folks living down-fjord of Jakobshavn agree; ice-induced tsunamis regularly crash ashore in Ilulissat Harbor, 50 kilometers away from the glacier's edge. A phenomenon they've dubbed 'kaneling.' Rest assured, though, these waves are usually just 1/2 meter high or less when they arrive in the harbor, and they're mostly harmless...mostly. This [video] is a slightly more dangerous version of an ice-tsunami. And yes, that there at the end of the video, that's a couple of guys in a little boat fleeing for their lives.

Awesome Video of Greenland Glacier Disintegrating [via Discover]

Oil companies currently pump CO2 down into their reservoirs as a way of forcing more oil up to the surface. The process works, but it's on a small scale, and some scientists worry that the carbon dioxide won't stay put — in the case of an earthquake or future drilling, it could come bubbling right back up into the atmosphere.

But David Goldberg and his team at Columbia have figured out a better way — pump the CO2 down beneath 9,000 feet of water and then into volcanic basalts. There the greenhouse gas reacts with the rock, turning into carbonate (aka limestone, aka chalk) so even if there is an earthquake there shouldn't be anything to worry about.

Of course getting any material pumped into rock close to two miles below the surface of the ocean could be tough, but the researchers are targeting a site in the Pacific Ocean offshore of Oregon and Washington that's filled with vast expanses of basalt. They're going to try some land-based trials later this year, but Goldberg says things would go a lot faster if the US cared to up the ante by throwing a little more cash towards carbon sequestration research. From EurekAlert:

The United States currently spends about $40 million a year studying carbon sequestration, but nearly all of that goes to land-based research. "Forty million is about the opening-day box office for Finding Nemo," said Goldberg. "We need policy change now, to energize research beyond our coastlines."

Source: Proceedings of the National Academy of Sciences via EurekAlert

Anyone who's spent time with Newton's law of universal gravitation can tell you that we're all being pulled toward the center of the Earth. In fact, if you were to drill a hole through the Earth and jump through, you wouldn't fall to the other side and stay there — you would fall through the center, heading for the surface on the other side, and then be pulled back to the center by the gravitational force of the Earth. You would oscillate back in forth this way (with a period of about an hour and twenty minutes, by the way) until you ended up suspended at the exact center of the Earth. And you'd be stuck, unless you had some serious propulsion.

The virtual journey we're about to go on should be a little more straightforward — and a lot less dangerous.

0-35 KILOMETERS DOWN: THE CRUST

This is the outer shell of the Earth, and it comes in two categories: the continental crust, or the part right under our feet; and the oceanic crust, which is the layer of rock at the bottom of the seas. While the continental crust is composed mainly of silicon and aluminum oxides, the oceanic crust is made up of mafic rocks — that is, mostly magnesium and iron. The continental crust tends to be less dense than the oceanic crust, but both are formed by lower-density materials in the mantle that rise to the surface over time. Temperatures of the crust get higher as you venture further down, and they can reach up to 1000 degrees Fahrenheit on the boundary with the upper mantle.

35-2890 KM DOWN: THE MANTLE

Here's where it gets interesting. Though the crust and the upper mantle (up to about 660 km down) are effectively solid, after that temperatures become so high that the material of the mantle becomes plastic — which means that under a certain level of stress, the body of the lower mantle actually begins to flow like a liquid. In the movie Journey to the Center of the Earth, what sent our heroes running was lava at 200 degrees Fahrenheit; I wonder what they'd do if someone told them that temperatures in the mantle range between about 1000 to 7200 degrees Fahrenheit.

Because of the mantle's plasticity, deformation of the metals can occur in areas called "subduction zones," and over time these metals change location within the mantle layer. Extreme pressures near the bottom — try about 1.4 million atmospheres — cause the material to deform like a fluid, and it rises up to relieve the pressure. Below about 650 kilometers, all of the minerals in the mantle start to destabilize and convect like this. Once they reach a higher point in the mantle, however, the release of pressure and the cooler surrounding area lead to a drop in temperature of the stressed metals. The lower-density metals can also rise to the upper boundary, eventually becoming part of the Earth's crust. This entire "downwelling" process is extremely chaotic — that is to say, freakishly nonlinear. But it works.

2890-5150 KM DOWN: THE OUTER CORE

As less dense materials and their chemically-bound buddies migrate to the Earth's crust, the denser metals remain in liquid form as a layer surrounding the Earth's core. In the outer core, these metals are mostly iron and nickel, heated at temperatures approximately between 7200 and 9000 degrees Fahrenheit and pressurized to over 1 million atmospheres. The film features a biosphere at the core heated by explosive gases, but that's, um, just plain wrong. It also shows our intrepid explorers heading to the core through "volcanic tubes," but as classic as the wooden-railed mine cart ride is, that's a fantasy that would disappear instantly into molten rock under the extreme heat and pressure of the outer core — not to mention the mantle first.

Since obviously no one can get down this far (the deepest humans have gotten is a smidge over 12 kilometers), seismologists have determined details about the mantle and the core by analyzing reflections and refractions of earthquake waves at the surface. They also estimate that convection in the outer core is responsible for sustaining the Earth's magnetic field, or magnetosphere — that's a concept that's very confused in Journey when Fraser and his cohorts leap across "magnetic rocks" at the center of the planet. In case you're also confused by the giant overhanging mushrooms and the ethereal beauty of the caverns and waterfalls, let me clear that up for you: They don't exist, either.

5150 KM DOWN TO CENTER: THE INNER CORE

The inner core of the Earth is a solid ball of metal — specifically, nickel and iron (just like in the outer core). So you can say goodbye to the fantastic creatures of Verne and Brevig, because there's nothing alive down here. The pressure at the center of the Earth is over 3 million atmospheres, and geologists estimate that the temperature can rise to over 10000 degrees Fahrenheit; even Brendan Fraser can't withstand that. It's the extreme pressure that "freezes" the inner core into a solid, and in fact, scientists believe that the inner core was liquid until 2-4 billion years ago.

A 2005 report in Science claims that the inner core rotates about 0.3 to 0.5 degrees more per year than the Earth's surface. This "super-rotation" probably acts to stabilize the magnetic field created by the outer core, so you have the inner core to thank for your working compass. And in case mine-cart rollercoasters, jagged stalactites, and huge 'shrooms don't do it for you, remember that the real center of the Earth is a spinning sphere of superheated metal. Not too shabby, eh?

"Structure of the Earth" [Wikipedia]
World Book at NASA: Earth [NASA] Earth images by Jeremy Kemp and SEWilco from Wikipedia.

Freund's theory has been around for years, and it basically goes like this: when squeezed, rocks turn into big batteries. Oxygen molecules in the rocks undergo chemical reactions, which builds up a positive electrical charge. When a big enough section of rock is under a lot of stress, the charge becomes strong enough to cause a disturbance in the planet's ionosphere.

Satellites orbiting in the ionosphere should be able to detect those changes (they may even mess with GPS satellites a bit), and one report says they already have:

Other proponents [of the prediction theory] expect new research confirming their theory will appear later this summer, based on a leaked memo written by Dimitar Ouzounov, a NASA-funded researcher at George Mason University.

On May 2, 2008, Ouzounov was looking for these same infrared light sources and found one over Sichuan province. Ouzounov sent a memo to colleagues reporting his finding, which he said was later leaked to the press.

On May 12 a magnitude 7.9 earthquake struck the Chinese province, killing thousands.

If this proves to be true, it's the holy grail of earthquake research. Imagine being able to predict quakes better than any other natural disaster (when was the last time someone accurately predicted where a hurricane would strike ten days in advance?).

But there are still two big red flags here: 1) if this is so awesome, why isn't NASA falling all over itself to get Freund's satellites in orbit? 2) if Freund has ponied up $1 million in personal cash to see this project through, he's probably going to want to make his money back. Fair enough, but things could get ugly if he builds one of the most potent life-saving technologies ever invented, but holds the information for ransom, charging world governments a subscription fee to protect their citizens from disaster.

Source: Discovery News

The Sun is obviously the biggest reason we're alive today — without it Earth would be a lifeless, frozen lump of rock at best. The same is probably true of the oceans, Earth's distance from the Sun, and so on. But Earth's magnetic field doesn't get enough credit (apart from a few terrible movies like "The Core") as being just as important as any of those ingredients for keeping life on Earth. Without it, highly energetic particles from the Sun would fry life, shatter life-giving molecules floating in the air and water, and strip away most of our atmosphere (witness Mars, whose thin atmosphere has been ravaged by solar winds).

In just a few centuries that may be a reality. Even if the field doesn't disappear entirely, in a weakened state it could let enough radiation in to cook the vast communications networks and power girds that have sprung up around the planet in the last century. But searching through ancient copper mines in Israel and Jordan has turned up some interesting new evidence. By looking at layers of metal slag that aligned themselves based on the magnetic field that was present as they cooled thousands of years ago, scientists at Scripps Institute of Oceanography and UC San Diego have managed to reconstruct the field's strength. What they found was startling: about 2,000 years ago Earth's magnetic field peaked in strength, and it's been weakening ever since.

The field itself isn't going away any time soon — it's powered by oceans of molten metal churning at the center of the planet — but for reasons we don't quite understand, every quarter million years or so it reverses polarity. Each time it does this, there's a period of a few days to a few hundred years where the field becomes so weak that it's almost non-existent, and that's what we seem to be heading for.

What does this mean for life on Earth? Bottom line is we don't know. Some scientists have argued that mass extinctions line up with field reversals in Earth's past, while others say that when the field flips it flips too fast — maybe over the course of a week or less — to do anything more than cause a glitch in your cell phone reception.
The one thing we can take comfort in is that the decline has so far been slow and steady, so humans alive today probably won't have to worry much.

But our fuzzy understanding from the geologic past suggests that as the field weakens further, it's polarity can wander all over the place, flopping back and forth like a fish out of water. If that's true, in a couple of generations global warming from CO2 in the atmosphere might be the least of our worries.

Source: Scripps Institute of Oceanography

As you scan through the data (Hole G, section 8 is where the action is, really), you can almost imagine running your fingers along the fault. The images are side-by-side photos, taken from opposite sides of the drill cores. Admittedly, they're not as sexy as a lot of the eye candy we usually link to. But they're beautiful in the same way images of the comet Shoemaker-Levy 9 slamming into Jupiter in 1994 were beautiful. Looking at them, it's hard to ignore that little voice inside saying "wow, that could happen to us."

Source: Earthscope.org via Discovery News

Above is a picture taken a few days ago of the ash plume. According to PhysOrg:

The ash plume, which is thousands of feet high, indicates an unknown geophysical change deep inside the volcano. Scientists also said small amounts of lava erupted from the crater Monday.

The National Park Service has closed Crater Rim Drive through the south caldera area until further notice, and people with asthma and other breathing problems were told to avoid downwind areas. USGS said the possibility of future small explosions from Halemaumau Crater cannot be ruled out.

Kilauea Spews Ash [PhysOrg]