The event and record of plate tectonics
Plate tectonics arises from two words and phrases; plate and tectonic. Plate in geological conditions implies a considerable slab of tricky rock even as tectonics in Greek implies’ to build’. Therefore’ plate tectonic is usually described as how the earth’s builds on moving the plate. It could even be well-defined as being a phase with the Earth’s lithosphere that could be rigid moves distinctively from these bordering it (Rodger, 1993).
Idea of plate tectonics states the lithosphere belonging to the earth is designed up of individual plates that fragmented into a few considerable and minor items of reliable rock. The plates go future to one another along with the decreased mantle to create assorted varieties of plate borders that have shaped the Earth’s landscape over most years. (Oreske & Legrand, 2001).
Alfred Wegener, a populous meteorologist, is known to be the founder on the plate tectonic theory. He noticed that the coastline of East South America and that of your west coast of Africa seemed to fit together in a jigsaw manner like to form a bigger plate. He then proposed an idea that all plates (continents) connected to a single large plate called Pangaea which gradually began to drift apart over 300 million yrs ago (Rodger, 1993).
More scientific research on the plates’ coastline revealed that all the plate of earth’s continent somehow fit together. The principle, commonly known as continental drift idea, and Wegener became the founder with the idea on which scientist have based on their research.their explanation
However, Alfred Wegener plate tectonics theory could not ascertain how exactly the continents drifted away from every other. He proposed the earth’s rotations and the centrifugal forces towards the equator as one from the possible mechanism for continental drift. He said that Pangaea started at South Pole and earth’s rotation finally caused it to break up, sending continents toward the equator. His theories were discarded by the scientific community (Rodger, 1993).
Arthur Holmes, (1929), a British geologist, came up with the concept of thermal convection to explain the gradual drift in the Earth’s continents. He based on heating and cooling cycle belonging to the Earth’s mantle that caused the continents to go. The Wegner’s idea being borrowed by scientist community in their quest for earth’s shape.
Today scientist have researched and analyzed past items of evidence and findings by geologist and scientist to expound and come up with a better ways of explaining plate tectonic idea and forces that were behind the drifting of the plates. It is believed and proofed using geological evidence that earth’s plate at one time was one big supercontinent called Pangaea. Due to three main driving forces namely, mantle convection, gravity, and the Earth’s rotation led to the drifting away of the a lot of plate from the main one. Many major plates (continents) formed which include North America, South America, Eurasia, Africa, Indo-Australian, Pacific, and Antarctica.
Expounding on the three main driving forces for the movement with the Earth’s tectonic plates; Mantle convection is the most extensively studied technique of tectonic plate movement. It was widely discussed by Holmes in 1929, in his concept. The sizable convection current of molten material in the Earth’s upper mantle produces a lot of energies which is transferred to lessen mantle. The reduced mantle material finds their way to the crust causing the embedded rock to shift away and out from the ridge thus moving the plate. Evident of this is present in mid-ocean ridges.
Gravity evidenced by the mid-ocean ridges where the elevation is higher than the bordering ocean floor. Convection currents within the Earth cause decrease mantle material to rise and spread away from the ridge, causing the older material to flow toward the ocean floor due to gravity and aid in the movement from the plates. Then lastly earth rotation is caused by centrifugal forces as the earth rotates (Oreskes $ Legrand, 2001).
Plates form different varieties on the boundaries as they interact with their movement. Some within the boundaries established include the Divergent boundaries form when a plate breaks along certain lines of weakness and go away from every other forming a new crust, for instance, Mid-ocean ridges. The other boundary is called Convergent boundaries and created when two plates collide with one another causing the sinking of one plate below the other. Transform boundaries forms at the location where new crust created and without destroying it.
Today, through research, scientists have come up with shreds of evidence proving that earth plates were once super plate that split into the current Continent. One belonging to the evidence is the jig-saw fitting with the East coast of South America, west coast of Africa appear to fit into one another. Also, Fossils remains of plants and animals collected by scientist around the world showed similarities that were cumbersome to explain unless continents had once joined. For instance, Cynognathus was a land reptile; its Fossils remain present both Africa and South America. Thus proving that the two continents joined as one, millions of many years ago, (Oreskes $ Legrand, 2001). Scientists have also found out from the evidence of earthquakes happened continually and occurred along certain lines, near the boundaries between tectonic plates.
As Wegener’s ideas form the basis why the landscape of the earth is the way it is, scientist community has advanced the methodology of studying the plate tectonic principle currently. They use the satellite to study evidences of plate tectonic where they position it scores of kilometers away from the earth surface. From the satellite statistics, it is evidenced that the plates go linearly and away from each individual other at the speed of 10mm to 100mm per year. Thus proving that plate tectonic theory that is earth was once one plate that gradually drifted apart about millions of yrs back to form the current continents.