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Middle school Earth and space science - NGSS
Plate tectonics and the ocean floor
NGSS.MS:
MS‑ESS1.C.2
, MS‑ESS2‑2
, MS‑ESS2‑3
, MS‑ESS2.A.2
, MS‑ESS2.B.1
Review your understanding of plate tectonics and the ocean floor in this free article aligned to NGSS standards.
Key points:
- There are two types of tectonic plates: oceanic and continental. Oceanic plates make up the ocean floor. Continental plates make up the continents.
- Both oceanic and continental plates are topped by crust. On average, oceanic crust is denser than continental crust.
- A trench forms when an oceanic plate collides with another plate at a convergent boundary. When this happens, the denser plate is subducted, or pushed under, the less dense plate.
- A mid-ocean ridge forms when two oceanic plates move apart at a divergent boundary.
- New oceanic crust is created at mid-ocean ridges. As it ages, it moves away from the ridge and becomes cooler and denser. Eventually, the crust reaches a trench and is destroyed.
Want to join the conversation?
Will the people go and look in the trench for other animals that haven't been seen before.(6 votes)
yes they will so we don't face them in the near future(1 vote)
can we see the plates move(2 votes)
Tectonic plates move too slowly for you to watch them move. They move about as fast as fingernails grow.(3 votes)
- why do waves in the ocean happen(2 votes)
- The common, constant waves that you see in the ocean are caused by wind. Storm surges, underwater earthquakes, and underwater landslides also generate waves, but those are relatively rare events.(4 votes)
why do earthquakes sometimes happen in the water?(2 votes)- Earthquakes always originate in rock. But because 2/3 of the planet is covered by water, earthquake epicenters are sometimes below water.(3 votes)
can people go in a trench, find megalodon DNA, and bring it back?(2 votes)
How do scientists believe that the world would fit together and make a giant country/puzzle basically(1 vote)
Because, proof shows that all of the contents would fit together!(2 votes)
- how many plate tectonics do we have(1 vote)
The surface of the Earth is divided into 7 major and 8 minor plates.(2 votes)
- In what way, are oceanic and continental plates different?(1 vote)
- Oceanic plates are made of Basalt, which is denser then what Continental plates are made of, which is Granite. Continental plates make up the continents, they are underneath the land masses on earth, while Oceanic plates are the plates under the oceans of earth. When an Oceanic and Continental plate meet, the Oceanic plate is always pushed under the Continental plate because the Oceanic plate is made of Basalt, which is denser then Granite, and Granite makes up the Continental tectonic plates.
I hope this helps.(2 votes)
- Can people go can see the plates move.(1 vote)
No, they move too slowly, and are underground(1 vote)
how are the plats developed(1 vote)