All Bout Plate Tectonics
By: Jayden Smith
Divergent Plate Boundarys
A divergent boundary is when two plates (oceanic or crust) move away from each other. When two continental plates move away from each other they create a rift valley, and when two oceanic plates move away from each other it creates a mid-ocean ridge. The mid-ocean ridge is responsible for sea-floor spreading because magma rises from the earth and it cools to form new land, where as the older land is farther away at the coasts and the young land is in the middle of the ocean. Divergent also proves the theory of continental drift created by Alfred Wegner, he stated that the continents used to be all connected (known as Pangea). All of the continents seem to fit together like a puzzle, and fossils of the same organisms were found on two different continents.
Convergent Plate Boundarys
A convergent plate boundary is when two plates (either continental or oceanic) collide with each other. When two continental plates collide with each other they will most likely form a folded mountain range, whereas when a continental and an oceanic collide, it causes convergent subduction and the oceanic plate will go under the continental plate because it is less dense than the oceanic. The process of convergent subduction will form trenches and volcanic mountains.
The Layers of Earth
The Earth is composed of three main layers, the core, the mantle, and the crust. The crust is responsible for holding all known types of life forms. The mantle is a hot layer of magma and other semi-cooled rocks and minerals. The core is the hot center of earth, which is a ball of metal. Throughout these layers convection currents circulate magma through different layers to footmen reheat closer to the core. These convection currents are what keep the tectonic plates moving and active so without the magma there wouldn't be any landlords and we'd still be together in Pangea.
More On Sea-floor Spreading
Sea floor spreading is incorporated into meant processes, but its role in the continental drift is quite amazing. Sea floor spreading is caused by plate tectonics and so is continental which means they are related somehow. When two plates move away magma comes up to form new land, pushing out old land, so sea-floor spreading is continental drift within itself. The man who came up with the theory of sea-floor spreading is Harry Hess, he believed that the continents were connected and had to of drifted apart and that there had to be some sort of underwater spreading.