Continental Lithosphere And Its Effect On The Earth 's Continental Crust

As a tectonic plate slides into the mantle, the heat releases fluids trapped in the plate. Seawater and carbon dioxide, rise into the upper plate and can partially melt the overlying crust, forming magma. And magma most likely means volcanoes are around.

The new volcanic material welling up into the void, which forms a ribbon of new materials and breaks down its center gradually, when the plates move apart from the axis of the mid-oceanic ridge system. Therefore, every separating plate accretes one half a ribbon of new lithosphere, and, thus, a new surface is added (Pitman, W.C, 2007). The process is continuous, and separation is always happening at the

The theory of plate tectonics states that Earth’s outer shell is divided into plates. The crust and upper mantle is broken into plates that move around on the mantle, changing in size throughout time. The lithosphere makes up the crust and upper mantle and the asthenosphere a plastic like layer beneath the lithosphere. There are three types of plate boundaries. Divergent boundaries where two plates move away from each other. The ocean widens and new crust forms at the mid-oceanic ridge. Convergent boundaries has three types of converging, moving two plates towards each other. First we have an ocean floor plate that collides with a less dense continental plate. Next an ocean floor plate collides with another ocean floor plate. Finally a continental plate collides with another continental plate. Transform boundaries were two plates slide past one another. The resulting effects of plate tectonics is landforms such as rift valleys,

To support the theory of continental drift is through topography, surveying the floors of oceans, charts of rock magnetism, and statistics on rock ages (Trefil & Hazen, 2010). At one time scientist believed that the deep ocean floors were flat; accumulating the sediment that progressively wore away from the prehistoric landmasses (Trefil & Hazen, 2010). However, they discovered steep-walled valleys and elevated highlands. This was evidences that just as the continents are transformed and are active, so to is the seafloor (Trefil & Hazen, 2010). The Mid- Atlantic Ridge, positioned in the central part of the Atlantic Ocean, is recorded to be the longest mountain range on this planet. Volcanoes, lava flow, and earthquakes are a source of

If new crust is indeed being produced at the rifts, where does the additional older crust go?

Plate tectonics is the scientific theory that attempts to explain the movements of the Earth's lithosphere that have formed the landscape features we see across the globe today” (Briney). Geology defines “plate” as a large slab of solid rock, and “tectonics” is part of the Greek root word for “to build.” Together the words define how the Earth’s surface is built up of moving plates. The theory of plate tectonics dictates that individual plates, broken down into large and small sections of rock, form Earth’s lithosphere. These fragmented bodies of rock move along each other atop the Earth’s liquid lower mantle to create the plate boundaries that have shaped Earth’s landscape. Plate tectonics originated from meteorologist Alfred Wegener’s theory, developed in the early 20th century. In 1912, he realized that the east coast of South America and the west coast of Africa appeared to piece together like a jigsaw puzzle. He further examined the globe and deduced that all of Earth’s continents could somehow be assembled together and proposed the idea that the continents had once been linked in a single supercontinent called Pangaea. To explain today’s position of the continents, Wegener theorized that they began to drift apart approximately 300 million years ago. This theory

The earth’s crust is made out of plate tectonics. Each plate has a defined boundary and direction it moves. The plates in Earth’s crust perform two actions; they submerge under each other or they spread out. The Pacific Plate is the largest plate and it borders around many plates. The Pacific Plate moves northwest. New crust is formed from magma outpours, which are a result of the zones spreading. The tectonic plates created the islands. When the tectonic plates move, it creates the change in geography. Active volcanoes together shape the way islands are build. The magma from the volcano and the deposits from the plate are needed to create

Plate tectonics move land masses around, and occasionally, interactions between different plates causes new land to form, and can even join two separate continents together, changing ocean currents and causing climate change. This is evident in the collision of the North and South American continents, which created the Isthmus of Panama, and separated the Pacific and Atlantic Ocean. Approximately 15 million years ago, the North and South American continent was cut off from each other by a seaway about 200 km wide. Over time, the South American plate collided with the Caribbean and Cocos plate, and gradually closed the exchange of the Caribbean and Pacific waters 3-4 million years ago. This resulted in several consequences.

The three major types of tectonic plates are divergent, subduction and transform. Divergent plates tend to move apart from each other. Subduction plates are when oceanic plate moves under a continental plate. This can cause volcanos to erupt and large sized earthquakes. Transform plates slide back and forth against one another. The Lithosphere consists of the Earths crust and uppermost mantle. The North American plate and the South American plate are the major plates of the lithosphere. The lithosphere also consists of the Pacific plate, the African plate and the Eurasian plate. The Pacific plate is the only major plate that is mainly underwater and is also the largest plate in the lithosphere. The Earth was once one large continental body called Pangea, before the plates started

For millions of years the Earth has experienced geologic catastrophes. Since the existence of Theia itself, the Earth’s crust has been formed, deformed, and even demolished. The crust has never been a completed masterpiece due to this. Why is this? The most recent physical changes were caused by the theory of plate tectonics and earth’s crust displacement. Plate tectonics and its movement resulted in our continents drifting across the earth’s surface, and the creation of mountain belts, volcanoes, and the faults of today’s Earth.

Have you ever wondered why our continents are in the positions that they are in today? Plate Tectonics can be used to explain the movement of the plates and the landforms they make. These landforms include mountains, volcanoes, rift valleys, and much more that are made by convergent and divergent boundaries. The plates are moved by the convection currents below the surface which is caused by a heat source, the mantle. Another landform that is made is a mid-ocean ridge, at which sea floor spreading is taken place, and allows magma to rise and harden on the ocean floor.

The Earth is constantly moving and this causes both earthquakes and volcanic eruptions to take place. As the plates drift and collide into each other, pressure builds beneath the surface of the earth. If it occurs near a fault, then an earthquake results. If the pressure is near a volcano, then the volcano will erupt. Sometimes the surface near a volcano will experience many small earthquakes before an eruption. The amount of pressure that is built up from the plates moving causes damage to the Earth’s surface. This can be seen at the Mid-Atlantic Ridge. The seafloor is spreading apart in the Atlantic Ocean which is pushing the plates apart. The surface that is experiencing volcanoes from this is Iceland.

New Basaltic magma rises to the surface, cools and pushes the plates apart. The convection currents also help drag the plates apart and then pull them down at convergent boundaries. This can be seen at the mid-ocean ridges. Eruptions are non-violent with the exceptions of the East African Rift Valley where the recent eruption in 2002 in the Republic of Congo had a devastating effect on the local population, and where the ocean ridges rise up out of the sea such as in Iceland.

Finally unlike divergent plate margins convergent zones can have a continental plate colliding with an oceanic plate. In this instance the more dense oceanic plate subducts below the continental plate. This forms a deep sea trench similar to the oceanic plate’s convergence, close to the shoreline. Also volcanic mountain ranges may also develop further in from the shore due to rising magma and folding. Such ranges include the Andes Mountain Range (“Plate Tectonics”).

The direction of the convection can cause plate boundaries- opposite and away from each other will result in divergent plate boundaries and opposite but towards each