I was a geophysics graduate student and introductory course teaching assistant when a film called The Core came out in 2003. The professor of that class decided to round everyone up and take a field trip to the downtown movie theater for its release, knowing full well Hollywood’s track record for properly depicting how things actually work is spotty at best.
I think I saw a porno with that slogan.
It stated off well enough, with a description of the Earth’s magnetic field and how it’s generated by the motion of molten iron in our planet’s outer core. The oddly dashing scientists are correct that the loss of that field could in fact have dire consequences, as it’s thought to maintain a grip on our atmosphere of charged particles, preventing it from being blown away by the relentless solar wind. Such a fate may have befallen our ruddy neighbor Mars, which lost its magnetic field 4 billion years ago, and can now barely hold on to some wispy clouds and a little carbon dioxide.
A depiction of Earth’s magnetic field as produced by the “dynamo” action of the molten inner core, courtesy of Science News.
It all fell apart quickly, though — both the situation faced by the protagonists and the possibility of the same. The outer core stops rotating somehow, without causing immediate global catastrophe, a violation of the law of conservation of momentum. A brave crew agrees to pilot an impossible ship coated in a fictional material deep into the Earth’s interior to “kickstart” the molten core’s rotation with nuclear charges, although it’s unclear how that’s supposed to work and where they stored such an expansive payload. On the way, our heroes encounter geology fantastic enough to make hollow earth theorists blush.
Just to be clear, there aren’t enormous, black diamonds floating around in the Earth’s mantle. The pressure is too high for empty spaces to exist and all our carbon is nearer the surface, anyway.
At least it ended on a high note, when Major Rebecca Childs (played in a “She was in that?” capacity by Hillary Swank) remarked to Dr. Josh Keyes that, “NASA could use a few good men like you.” His rejoinder of, “Unfortunately, so could my freshmen geophysics students,” earned a fist-pump from my professor. But ultimately The Core is just another in a list of dodgy disaster flicks; following 1997’s Volcano, which confuses California’s strike-slip tectonics for a subduction zone, and leading to NBC’s 2004 mini-series 10.5, the tale of an earthquake so impossibly big it could only occur on a fault that encircles the entire planet.
Tommy Lee Jones would be relieved to know that volcanoes can’t possibly occur in California. They’re symptoms of one tectonic plate diving beneath another and melting, whereas the famous San Andreas fault is characterized by lateral motion as two plates slide past each other.
What’ll the next one have, mysterious islands popping up out of the ocean?
Wait, that actually just happened.
Stranger than Fiction?
A magnitude 7.7 earthquake struck rural south-central Pakistan last Tuesday, killing over 300 and destroying as many as 250 homes. Temblors in that region are not uncommon, as Pakistan is sandwiched between several active plate boundaries, including where the Arabia plate subducts northward beneath the Eurasia plate and the zone where the Indian subcontinent has slammed into the rest of Asia and continues trying to slip by.
September 24th’s Awaran earthquake occurred in a busy part of crust.
The motion of this particular event was strike-slip, so don’t expect any explosive lava projectiles, yet an entire new island still seems to have appeared off the country’s coast. I had never heard of such a thing, but apparently it’s not all that uncommon. In fact, this is the fourth time in recent history Pakistan has observed something like this, the previous one happening just in 2011.
Satellite image of the new topography, taken by the French Pleiades space project.
Satellite measurements peg the nearly circular interloper’s area at about 250 ft.2, reaching 60-70 feet into the sky. Its composition seems to be mostly mud, with some rocks strewn on the surface. If history is any indication, the feature will only be temporary, as all the others produced previously were eroded away by rain and ocean currents within a few months.
Take a walk on the weird side. Pakistani citizens traipse the new real estate while they still can. Photo from National Geographic.
The ephemeral island was likely created when gases beneath the surface pushed through material at the bottom of the sea floor after being released due to the earthquake’s rupture. Reports indicate that some of them are still bubbling and hissing at the surface, and that they can even catch fire! U.S. Geological Survey geophysicist Bill Barnhart is skeptical of that last bit, however, as there shouldn’t be buried methane deposits that close to shore. He says the more likely culprit is simply CO2.
Still, a transient, instantaneously appearing mudball that emits noxious gas? That’s wild enough to be part of even the most far-fetched disaster scripts. Eat your heart out, Hollywood.
Don’t forget that if you’ve got a burning question about the science in a recent comic book, movie, TV episode, whatever, e-mail me at firstname.lastname@example.org and it might become a future column!