Plate Tectonics
PLATE TECTONICS
HI! Today, We're going to learn what is plate tectonics and theory behind it. Without further ado, let's get started!
Are you familiar with the word "Plate Tectonics"? It is is a scientific theory describing the large-scale motion of seven large plates and the movements of a larger number of smaller plates of the Earth's lithosphere.
The theory of plate tectonics has done for geology what Charles Darwin's theory of evolution did for biology. It provides geology with a comprehensive theory that explains "how the Earth works." The theory was formulated in the 1960s and 1970s as new information was obtained about the nature of the ocean floor, Earth's ancient magnetism, the distribution of volcanoes and earthquakes, the flow of heat from Earth's interior, and the worldwide distribution of plant and animal fossils.
The theory states that Earth's outermost layer, the lithosphere, is broken into 7 large, rigid pieces called plates: the African, North American, South American, Eurasian, Australian, Antarctic, and Pacific plates. Several minor plates also exist, including the Arabian, Nazca, and Philippines plates.
The plates are all moving in different directions and at different speeds (from 2 cm to 10 cm per year--about the speed at which your fingernails grow) in relationship to each other. The plates are moving around like cars in a demolition derby, which means they sometimes crash together, pull apart, or sideswipe each other. The place where the two plates meet is called a plate boundary. Boundaries have different names depending on how the two plates are moving in relationship to each other.
*The lithosphere is the outer solid part of the earth, including the crust and uppermost mantle. The lithosphere is about 100 km thick, although its thickness is age dependent (older lithosphere is thicker).The lithosphere below the crust is brittle enough at some locations to produce earthquakes by faulting, such as within a subducted oceanic plate.
FUN FACTS:
The plates are all moving in different directions and at different speeds (from 2 cm to 10 cm per year--about the speed at which your fingernails grow) in relationship to each other.
Earth is the only planet known to have plate tectonics.
In 200 million years the world will look much different compared today. This is because some of our present day continents may be split apart and be separated by new oceans.
That's all
Thank you!
References:
http://www.cotf.edu/ete/modules/msese/earthsysflr/plates1.html
https://earthquake.usgs.gov/learn/glossary/?term=lithosphere
https://www.nationalgeographic.com/science/earth/the-dynamic-earth/plate-tectonics/
https://en.wikipedia.org/wiki/Plate_tectonics
http://slideplayer.com/slide/4149480/