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Oceanic Seismic Activity. (A.K.A. When things go boom!). Volcanic Islands.
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Oceanic Seismic Activity (A.K.A. When things go boom!)
Volcanic Islands • Hawaii is a great example of a chain of volcanic islands. They are created by underwater volcanoes (seamounts). Each time a seamount erupts, a new layer of hardened lava forms, enlarging the size of the volcano. The seamount peaks above the surface waters, and it is now called a volcanic island.
Oceanic Plates • In this picture, the platter is bordered by silverware. An oceanic plate is the same. The platter represents the oceanic plate, and the silverware represents the continental plates.
Continental Plates • The same is true in this picture, except the other way around. Every continental plate is either bordered by a different continental plate (fork), or an oceanic plate (spoon).
Quick Fun Fact: • A volcano’s cloud of ash can become electrically charged and spark lightning.
Converging Plates • This very moment, plates are converging, or coming together / moving apart. Effects of this include volcanoes, seamounts, and tsunamis.
The word tsunami comes from two Japanese words: “tsu” and “nami”. (How much simpler could it be?) The word tsu means harbor. The word nami means wave. Seriously, it’s a compound word. Tsunamis are formed when there is a disturbance on the ocean floor, such as an earthquake or seamount eruption. Some parts of the ocean floor are lifted up, and some are dropped down. Whatever happens on Tsunamis
Tsunamis (continued) the ocean bottom is mirrored on the surface, creating a massive wave. Nature evens things out pretty quickly, but seismic activity created the wave, and it doesn’t just disappear. The water is flat on the surface, but underwater waves are creating deadly vibrations, rushing through the water at speeds of up to 970 kph. Unlike surface waves, tsunamis can extend thousands of feet into ocean depth. They carry lots of water and energy, so they can travel extremely long distances, up to 16,000 kilometers long.
Tsunamis (almost done!) There can be hundred of miles between the crests, and the waves are practically invisible to people. When the wave collides with the shore, the vibrations run out of room to keep going. The waves slow down and pack together. The water swells, forming a wall of H20. Its force can plow through houses and level buildings. Depending on the shape of the ocean floor, the wave can take different forms. Usually it is described as a rapidly rising tide. Some coastlines can slow it down enough to push it into a massive wave…that =bad events. Destruction follows the wave to land. It takes an earthquake with a rector scale reading of 7.5 to generate a huge tsunami, but smaller earthquakes can still produce a lot of damage like…
Not the good guys! Bad guys.
I am sorry to say that the news reporter for that update is most likely no longer with us.
The currents in an ocean don’t come from just anywhere. The patterns of the currents are called gyres. Each gyre is bordered by a continent. Gyres! Gyres
Danger Zones • All of the continental plate / oceanic plate friction areas around the Pacific come together to make the Ring of Fire, a nickname given to it because of all of the volcanoes. This makes them touchy, and
