The Big One Is Coming. Here's How We Know, And How To Survive

The Big One is coming.

Nope, the big one isn't a new Burger King special, and it's not the ironic nickname of a rowdy chihuahua. It is the name of a body pillow brand, but that's not what we're talking about.

We're talking about an earthquake with a magnitude around 8.0 expected along the San Andreas fault. It's a quake that could crush buildings, roads and homes in California; that could wipe out water mains, electricity and internet connectivity; that could overwhelm medical facilities and leave millions stranded for weeks.

Sounds like something to prepare for, right? The only problem is, we have no idea when it's coming.

Technically, we don't. Earthquakes are notorious for being almost complete surprises. Even as we've learned to track and predict other extreme weather and geological events such as floods, hurricanes and volcanic eruptions, earthquakes remain almost totally under the radar (no pun intended) until they strike.

That's largely because earthquakes start from deep within the Earth, far deeper than we've been able thoroughly explore or understand. Its only been since the 1950s that scientists have understood our Earth enough to develop the plate tectonics theory.

That theory says that the outer shell of our planet, known as the lithosphere, consists of major and minor tectonic plates which make gradual movements – by gradual, we mean maybe 4 inches per year – as the Earth rotates. Those movements don't typically cause enough friction for us humans to feel.

But sometimes, the shifting of the plates causes tectonic plates to bump into each other on the boundaries of the different plates, known as fault lines. The edges of the plates get stuck along the fault as the rest of the plate keeps moving, which causes a bit of a jam along the fault. As energy builds, it has to go somewhere. Unfortunately, that somewhere is the surface of the Earth, and it shakes and quakes as it bubbles to the surface.

While we have this knowledge of earthquake origins, though, we can't get far enough into the Earth to have sensors to see when that tension is building. And unfortunately, earthquakes don't give many (if any) warning signs. Throughout the years, scientists have looked to different factors including increased radon in local water sources, electromagnetic changes and even odd animal behavior.

But none have been reliable predictors. So seismologists have had to look to history and do some math. They know the San Andreas fault, a major fault line which extends for about 750 miles along California, is a hotbed for seismic activity.

The Northern part of the San Andreas Fault saw a 7.9 magnitude earthquake in 1906. Despite the area not being nearly as populated as it is today, the event led to damage including devastating fires, more than 3,000 fatalities and an estimated 80 percent destruction of the city. The middle of the fault saw a 7.9 earthquake in 1857.

But the southern part? That hasn't blown in about 300 years. Many seismologists believe it's a boiling point set to send off a quake of around 8.0 magnitude at any time.

You probably know most earthquakes aren't catastrophic. More than 1 million small quakes per year occur relatively regularly, both underwater and on land. People don't even feel about 900,000 of those, and the rest typically don't cause much damage beyond some startled people and broken picture frames. Those typically measure below 5.4 on the Richter scale, the tool used to measure the severity of earthquakes.

But the Richter scale is logarithmic, so when we talk about The Big One measuring 8.0 and hitting the second-biggest city in the U.S, the damage starts to get real.

An earthquake of this magnitude has a few different modes of destruction. First, there's the initial impact. With zero warning, the quake can cause buildings to fall and crush cars, buses and people. Broken power lines can lead to fires that burn infrastructure, humans and animals. Mudslides or landslides can smother people. Crumpled buildings can injure or kill its inhabitants.

Then, there are the aftershocks. The smaller quakes that follow an initial impact can lead to similar or greater destruction as the initial quake, since they're hitting infrastructure that has already been severely weakened.

Lastly, there's the aftermath, which is different from the aftershocks. Even after the land has settled, the destruction will remain. Since the quake has the power to destroy water mains, electric lines, telephone lines, Internet connectivity and roads, people may have to live for weeks without a water supply, access to grocery stores and medical facilities, adequate shelter, heating and cooling or really any connection to the outside world.

Yes! Look, we know it sounds dire, especially that whole "this could happen literally any minute!" part, but if you're a Southern Californian, there are definitely measures you can take to prepare. Here are a few of the best things to stock up on, according to B-526EarthquakeSafetyChecklist110217508.pdf'>FEMA:

• Water: This is the single most important thing. Try to have two weeks' worth of clean water. Experts put that at one gallon of water per person per day. Additionally, try to stock up on water purification tablets that can help give you clean water from outside sources in case your supply runs out.
• Non-perishable food: Avoid foods that take up much space, as well as those that make you thirsty. Get canned goods with high liquid content, sodium-free crackers and foods high in protein like peanut butter. If you care for family, make sure you have foods for their specific needs, such as infant formula.
• First Aid kit
• Fire extinguisher
• Miscellaneous: This could be anything that you need on a regular basis, such as an extra two weeks' worth of contacts, medication, diapers, pet food or feminine hygiene products.
• Battery powered radio: Don't forget that electricity could be down for a significant period of time. Get a radio that can help you get news about the overall situation, as well as several extra supplies of batteries. 
• Battery powered flashlight
• Documents and cash: Banks, point of sale tools that take debit and credit cards, ATM machines and your phones containing digital copies of important documents may all be inaccessible. Have a stash of cash in case you have the opportunity to pay for more supplies, as well as identification cards in case you need them.

You should also know where to go! If you're indoors, try to get under a heavy piece of furniture that can stand up against a quake. That could be under a heavy desk, or against a wall. When you're there, drop to the ground, cover and hold on to something sturdy if you can. Stay away from things in danger of falling or breaking, such as glass windows or chimneys.

If you're outside, whether walking or in your car, try to get to as high of ground as you can. Stay as far away as possible from any wires, trees, streetlights, buildings, overpasses or anything else in danger of falling. Beware of aftershocks as you make your way to safety.

This is a lot of information about an earthquake that may or may not be headed your way anytime soon. But the more you know, the better you can prepare, and the better off you'll be when The Big One strikes.