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You may have read that 2018 is looking to be a bad year for earthquakes, but Hank is here to offer you some assurances.

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Sources: https://earthquake.usgs.gov/learn/kids/eqscience.php
https://www.sciencealert.com/real-science-behind-major-earthquake-predictions-2018
http://time.com/5031607/earthquake-predictions-2018/
https://www.theguardian.com/world/2017/nov/18/2018-set-to-be-year-of-big-earthquakes
http://onlinelibrary.wiley.com/doi/10.1002/2017GL074934/abstract
http://temblor.net/earthquake-insights/can-changes-in-earths-rotation-be-used-to-forecast-earthquakes-5642/

http://advances.sciencemag.org/content/3/11/e1701593
https://archive.epa.gov/esd/archive-geophysics/web/html/seismic_reflection_methods.html
If you’ve been paying attention to the news, you may have seen some worrying headlines pop up over the last week or so.

Things like “2018 is going to be the worst year on record for major earthquakes” or “You better dig out an earthquake bunker because we’re definitely all going to die.” I mean, that one might be an exaggeration... but you get the idea. In a recent conference, scientists from the Universities of Montana and Colorado did present groundbreaking work related to earthquake prediction.

But it might not be as dramatic as the headlines make it out to be. The crust of the Earth is broken up into massive fragments called tectonic plates. Where these plates meet, and within plates, there are cracks called faults.

Because the pieces of the Earth’s crust are constantly moving in different directions, when different sides of a fault get stuck on each other and then move suddenly, you get a huge release of energy. That’s an earthquake. And we all know how devastating earthquakes can be, causing damage to buildings and people and all kinds of things.

So it’s not surprising that we want a reliable way to predict when and where they’re going to happen—the more time we have to prepare, the better. But it’s really hard to do. Which brings us to this research.

Two geologists, who published their study in August, noticed that there was a weird pattern to big earthquakes — about 7.0 or bigger on the Richter scale, the Richter scale is the international numerical scale for how strong an earthquake is. Basically, the higher the number, the more you feel it. Since the year 1900, they found that big earthquakes seemed to happen more often worldwide every 30-ish years or so — like, about 25 times a year instead of 15 times a year.

And, weirdly, they found that these waves of big earthquakes may be correlated to patterns in the Earth’s rotation. Now, the Earth’s rotation isn’t constant. The moon and gravity and other factors can slow it down by tiny amounts.

And these researchers found that right after several periods when the Earth’s rotation got slower, intense earthquakes happened more often. And they think it might be because the Earth’s crust is sitting on top of molten lower layers, so as the planet’s rotation slows a bit, the insides slosh around. Like, think about a cup of coffee in your car when you brake… it’s a similar idea.

It takes about five years for everything to sort of even out, and during that time energy might build up near faults. And that might be bad for the stability of the crust, and mean more big earthquakes. Or at least, that’s a possible explanation these researchers proposed.

Seismology is a super tricky science and it’s filled with uncertainty. The scientists point out that there’s still a lot of discussion within the community about what might cause a correlation between the Earth’s rotation and big earthquakes. And even though the last slowing down of the Earth started in 2011, which was more than 5 years ago, they’re also not predicting that 2018 will be apocalyptic.

Based on this data from the last 100 years, a bad year for earthquakes might be a little more likely to happen, but that doesn’t mean it’s definitely going to. … which should probably be seismology’s motto. Because even though statistics and computer models have helped researchers predict a lot of things, earthquakes are ridiculously tricky. We don’t even entirely understand all the things that might cause faults to start building up energy.

But this week, researchers published more data to suggest that we might be partly to blame—at least for earthquakes in certain regions, like the Central United States. Now, this isn’t a new idea. Scientists have been looking at this particular part of the US and its increase in earthquakes since 2009.

Studies from 2012 showed that earthquake frequency could be linked with natural gas extraction and wastewater injection — where unwanted, chemical-filled water from extraction processes is put back into the ground. The researchers suggested that these practices could change the pressure in naturally-occurring pockets of gas between chunks of crust in the central US and make the ground shift to compensate. They came up with these ideas using statistical models.

Basically, plugging in where earthquakes and drilling were happening and boom: correlation. I mean, it’s a bit more complicated than that. But the point is, no one had really looked at the rocks.

Until now. The scientists who published the paper last week used what’s known as Seismic reflection data to map the Earth’s crust in some of the known hot-spots in the central US. Seismic reflection is a technique kind of like SONAR, where researchers use special instruments to send vibrations through kilometers of rock below them.

Basically, these vibrations get reflected back towards receivers on the Earth’s surface, and give you information about what’s down there. It can be used to find things like natural gas and oil deposits, but seismologists and geophysicists use it to get an idea of what sort of rock is below the surface, like how old it is based on how deep it is, and how intact the layers are. When the scientists used recorded data to take a closer look at some of the faults in the central US, they found that some faults seem like they’ve been actively shifting for millions of years.

While others weren’t really… until—you guessed it—people started messing with the crust. Have we learned nothing from Sci-Fi disaster movies? That just never ends well.

Paul Giamatti is in a room somewhere, warning you For these scientists, this is evidence that this correlation between human activity and earthquakes is more likely. Sometimes with statistical models, it’s hard to be sure. And now that someone’s actually checked out the rocks, maybe we can start to do something about this increase in tiny quakes.

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