Extinction of the Dinosaurs
Why was the extinction of the dinosaurs so important?
I think that the extinction of the dinosaurs was a vital event in history because if they hadn't died, we may not be here. Even if humans did fill the earth while dinosaurs were alive, humans would not have been around for too long.
A subduction zone is the biggest crash scene on Earth. These boundaries mark the collision between two of the planet's tectonic plates. The plates are pieces of crust that slowly move across the planet's surface over millions of years. Where two tectonic plates meet at a subduction zone, one bends and slides underneath the other, curving down into the mantle. (The mantle is the hotter layer under the crust.)
Seafloor spreading and other tectonic activity processes are the result of mantle convection. Mantle convection is the slow, churning motion of Earth’s mantle. Convection currents carry heat from the lower mantle and core to the lithosphere. Convection currents also “recycle” lithospheric materials back to the mantle.