The Highest and Lowest points of the Lithosphere are both found at the Earths plate boundaries, with reference to the process of plate tectonics, explain why this is so.
The process of plate tectonics, also known as Orogenesis, has shaped Planet Earth to what it is today. The four different spheres; Lithosphere, Hydrosphere, Atmosphere, and Biosphere, have worked together to create a beautiful a gigantic Ecosystem where Fauna, Flora, Detritus Feeders (Bacteria and other Micro-organisms) and Decomposers have created a world to live in with the highest and smartest known species; the Human. Plate Tectonics has not only build our world but also helped to destroy it and to rebuild it in different shapes and forms.
The Earths Landmasses used to be joined together known under the name of Pangea. After millions of year the art of plate tectonics has moved this large landmass apart into smaller landmasses known as Continents and Islands. It is already estimated what the “Next Pangea” will look like, that would be 250 Million years from now (Figure 4.1). Through this process many new landscapes have been created. There are seven major plates that move between the earths surface and core, which is named the Asthenosphere. They are the Pacific Plate, Indo-Australian Plate, African Plate, North American Plate, South American Plate, Antarctic Plate, and the Eurasian Plate (Figure 6.1). The structure of the Earth can be easily shown in a diagram which is shown in (Figure 1.1) at the end of this document. The plates which are moved by the convection currents in different directions have therefore created and destroyed parts of the lithosphere, also known as Denudation (Process of breaking down the Lithosphere). These convection cells and their currents have moved these major plates in different directions through all this time. These movements have different names too. They are describes like this and diagrams are shown in (Figure 2.1) and
(Figure 3.1) at the end of the Document:
Constructive Margins- is when two plates move apart and away from each other letting Magma (the molten rock which belies under the earths crust) reach the surface where its then called Lava. It cools off and created to landmasses which are very fertile because of it’s large mineral content. This process forms Mid-Ocean Ridges and is sometimes known as Sea-Floor Spreading. Example: Iceland.
Destructive Margins- is when two plates move together and one plate is pushed under the other plate. This only happens when a Continental Plate and a Oceanic Plate move together. The Oceanic Plate is pushed under the Continental Plate because of it’s heavy mass of Ocean Water. As it slides under the lighter Continental Plate it creates a Subduction Zone which is the point where the Oceanic Plate is swallowed by the magma and melts to create more magma. One way for the pressure to be released is by Volcanoes which are very evident at the site of Destruction. Example: Andes Ranges, South America.
Collison Zones- is when two continental plates move together in equal force to create mountain chains, often known as Fold Mountains. None of the plates are pushed under like in the Destructive Margin because they both have no Ocean Mass on it and they move together with equal force which makes both plates fold upwards to create new mountain chains. Example: Mt. Everest, Himalayas.
Conservative (Passive) Margin- is when two plates move parallel to each other sliding next to each other without moving away or towards each other. These are also called Transform Faults. Example: San Andreas Fault, California.
These different methods of Orogenesis have created the earths upper layer on which we live on with all the other species. The earths highest and lowest points are therefore found on the plate boundaries because those are the areas where the plates interact to form and construct these higher and lower points. The higher and lower points are created by different methods of Orogenisis. For Example the Hawaiian Islands where not formed by any of these Margins. The Hawaiian Islands and its Volcanoes are Hot Spots (Figure 5.1). This means that at that particular spot the Lithosphere is very thin which lets Magma escape and therefore create Volcanoes and add new landmasses, Islands.
The Highest Point of the Earths Crust which is Mt. Everest in Nepal, has been created by the process of Collision Zones. The highest point of the earths crust that is Mt. Everest has been created when the Eurasian Plate and Indo-Australian Plate have moved together to collide and fold upwards. Mt. Everest has a height of 8,848 meters or 29,029 feet altitude. It is the highest point of the Earths Crust.
The Lowest Point of the Earths Crust which is the Mariana Trench in the Pacific Ocean has a depth of 10,920 meters or 35,827 feet. It was created by the process of Constructive Margins or Sea-Floor Spreading. The Eurasian Plate has moved away from the North American plate which spreaded the Sea Floor in the Pacific Ocean ceating the Mariana Trench; the lowest point of the Lithosphere.
Therefore, the process of Orogenesis created the Highest and Lowest points of the Lithosphere and because of the Plate’s Locations thanks to Convection Currents has created those wonders on the Plate Boundaries. There are more diagrams shown at the end of this Informative Document.