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e. Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') [1] is the scientific theory that Earth 's lithosphere comprises a number of large tectonic plates, which have been slowly moving since about 3.4 billion years ago. [2] The model builds on the concept of continental drift ...
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- Principles of plate tectonics
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German meteorologist Alfred Wegener is often credited as the first to develop a theory of plate tectonics, in the form of continental drift. Bringing together a large mass of geologic and paleontological data, Wegener postulated that throughout most of geologic time there was only one continent, which he called Pangea, and the breakup of this continent heralded Earth’s current continental configuration as the continent-sized parts began to move away from one another. (Scientists discovered later that Pangea fragmented early in the Jurassic Period.) Wegener presented the idea of continental drift and some of the supporting evidence in a lecture in 1912, followed by his major published work, The Origin of Continents and Oceans (1915).
Read more below: Development of tectonic theory
Pangea
Learn more about Pangea.
What is the cause of plate tectonics?
Although this has yet to be proven with certainty, most geologists and geophysicists agree that plate movement is caused by the convection (that is, heat transfer resulting from the movement of a heated fluid) of magma in Earth’s interior. The heat source is thought to be the decay of radioactive elements. How this convection propels the plates is poorly understood. Some geologists argue that upwelling magma at spreading centres pushes the plates, whereas others argue that the weight of a portion of a subducting plate (one that is forced beneath another) may pull the rest of the plate along.
In essence, plate-tectonic theory is elegantly simple. Earth’s surface layer, 50 to 100 km (30 to 60 miles) thick, is rigid and is composed of a set of large and small plates. Together, these plates constitute the lithosphere, from the Greek lithos, meaning “rock.” The lithosphere rests on and slides over an underlying partially molten (and thus weaker but generally denser) layer of plastic partially molten rock known as the asthenosphere, from the Greek asthenos, meaning “weak.” Plate movement is possible because the lithosphere-asthenosphere boundary is a zone of detachment. As the lithospheric plates move across Earth’s surface, driven by forces as yet not fully understood, they interact along their boundaries, diverging, converging, or slipping past each other. While the interiors of the plates are presumed to remain essentially undeformed, plate boundaries are the sites of many of the principal processes that shape the terrestrial surface, including earthquakes, volcanism, and orogeny (that is, formation of mountain ranges).
The process of plate tectonics may be driven by convection in Earth’s mantle, the pull of heavy old pieces of crust into the mantle, or some combination of both. For a deeper discussion of plate-driving mechanisms, see Plate-driving mechanisms and the role of the mantle.
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Learn about the theory of plate tectonics, which explains how Earth's lithosphere is composed of moving plates that interact along their boundaries. Explore the geologic and geophysical data that support this theory and its implications for Earth's history and evolution.
Mar 7, 2024 · Plate tectonics is a scientific theory that explains how major landforms are created as a result of Earth’s subterranean movements. The theory, which solidified in the 1960s, transformed the earth sciences by explaining many phenomena, including mountain building events, volcanoes, and earthquakes. In plate tectonics, Earth’s outermost ...
Learn about the Earth's plates, their movement, and the types of boundaries they form. See examples of convergent, divergent, and transform boundaries and how they shape the land and oceans.
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Learn about the movement and features of Earth's tectonic plates, the evidence for plate motion, and the types of plate boundaries. This article is aligned to NGSS standards and includes questions and tips for learners.
Learn about the theory of plate tectonics, how Earth's lithosphere is divided into rigid plates that move and interact. Explore maps, animations, articles and teaching ideas on plate tectonics, earthquakes, volcanoes, tsunamis and more.
Learn how the movement of Earth's plates shapes the geosphere and influences the climate and ecosystems. Explore the evidence, processes, and phenomena of plate tectonics with interactive models and examples.
