The ground begins to shake. Your phone goes off. It's an alert to something you already noticed. You hide in a doorway and hope your dishes don't hit the floor. Anyone who grew up in California will tell you this is not something out of a movie. It's an Earthquake!! Most people who live in earthquake prone areas know the feeling of the ground moving under them. But do they know why and how it's happening?

Our little blue planet can be divided into plates. To be specific, the Earth's crust is actually several individual plates that line up against each other. There are three different ways they interact together at their "boundaries". Divergent (not the movie) boundaries hate each other. They move away from each other when they can, causing magma to rise up and form new crust. This is more common with oceanic crust, but can sometimes be seen with continental crust. The Mid-Atlantic Ridge in the Atlantic ocean is a great example of this. This ocean is actually getting larger, which is a problem for Iceland, which sits on top of it. I wonder what they will call it when it is split in two. West and East Iceland?

Convergent boundaries have separation anxiety. They try to get as close to each other as possible. This occurs when the plates move towards each other. This anxiety ridden boundary gets complicated. It has three personalities. The first is ocean-ocean. When two ocean plates push together, one is shoved down below the other (I told you they have problems). As this subduction occurs, a trench is formed. The Aleutian Trench is a good example to look into for this. Keep in mind that this can cause Earthquakes.

The second personality would be ocean-continent. This one is fun because we get VOLCANOES!!! Like the ocean-ocean personality, one side of the fight will win out over the other in subduction. In this case, the thinner oceanic crust will lose and sink under the thicker and meaner continental crust. As this happens, sediments are pushed up and pressure and temperatures begin to build. This causes the formation of mountains and their more hostile cousins. Like any fight, something is bound to erupt. The magma will start to rise and boom! You have a volcanic eruption that will one day become a Blockbuster hit. If you have ever seen an image, or been lucky enough to see it in person, the Andes Mountain range is a beautiful example of ocean-continent infighting.

Have you ever seen your older sibling fight? You now it won't be pretty, but you can't really look away. This is the continent-continent personality. Like it sounds, this occurs when too continent plates try and get to close. When two tough guys get into it, will either side win? Both will fight to the death, and the one that loses will not go down easily. As the two come together, the push and push on each other (you thought the other personalities had problems) until one finally gives up. This one is usually older and denser. It just can't fight anymore and will start to sink. This plate, however, will keep trying for a while before it actually sinks into the mantle of the Earth. Because of all this pushing and chaos, mountains will start to form on the battle lines. This is not the family to share a holiday with. But if you insist on seeing all this immaturity, then trek to the Himalayas where you can see this type of convergent boundary of full display.

Transform Boundaries are completely indecisive. They don't want to stay too close, but they don't want to go too far either. The problem with this is they start to panic. Instead of really moving, they start to rub up against each other (I know it sounds awkward). The two plates will shift back and forth causing your dishes to fall out of the cabinets. This is where California gets it's shaky reputation. The San Andres Fault (yes the one in the movie) is famously active because the Pacific plate and the North American plate cannot agree on their commitment level to each other. It has kept southern California on it's toes for a long time.

While this plate thing may make your family seem well put together, just think of how boring our world would be every each one of them agreed all the time.

Works Cited:

Earle Chapter 10 Plate Tectonics

Science Terms https://scienceterms.net/geology/convergent-boundary/#:~:text=Continent-continent%20convergent%20boundaries%20are%20home%20to%20their%20own,great%20distances%20before%20eventually%20subducting%20into%20the%20mantle.

Many people may not realize this, but Earth has one ocean. It is divided into areas for naming and logistical purposes, but it is one big ocean. With that in mind, let's take a look down below and see what the sea is all about. You will hear terms like continental shelf, slope, and rise. Once you hear a word like Abyssal you will remember it. But what does it all mean?

On Earth, there is as much diversity below the water than above it. If you stand on the shore or beach, and start to walk into the ocean, you will notice that you don't just drop in. You walk and walk as you get deeper and deeper into the water. That is the Continental shelf as you get closer to the shelf break. This shelf is the very edge of the continent as you are about to leave "land". There is a break, a shelf break, and then you slide down the Continental Slope. This will go down some three to five thousand meters until it hits the thick sediment of the Continental Rise, the spot where continental meets oceanic, and after that comes the deep ocean itself. This deep ocean floor, like everything else in science, as a technical term, the Abyssal (I told you you would remember).

If you are having a hard time imagining what this under water world is like, just picture the land above. There are mountains and hills, valleys and plains. It's the same with the ocean, they just have different names. Take Seamounts for instance. Above ground, they would be called mountains. Or Ridges, which a long and narrow areas that have steep sides and can be a bit rocky. What would these be on land? Maybe a valley? How about volcanoes? Above ground they cause destruction, but in the ocean, they cause islands to form over time. Trenches, Plains (same above as below the water line), and even Canyons are these amazing things we see similarly on land as we do below that give our ocean or oceans character.

Works Cited:

References from Stewart Chapter 3 The Physical Setting and Webb Chapter 1 Introduction to the Ocean