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Tolli/Stapp 14
Tectonic Plates - 6.10CD
Term | Definition |
---|---|
Tectonic Plates | Huge pieces of lithosphere that slowly move on the asthenosphere and consist of the crust and the rigid, uppermost part of the mantle. |
North American Plate | A tectonic plate division of the lithosphere that includes the continental crust of Greenland, North America, Siberia, and the surrounding oceanic crust. |
Eurasian Plate | A tectonic plate division of the lithosphere, including most of the landmasses of Europe and Asia. |
African Plate | A tectonic plate division of the lithosphere that includes the continental crust of Africa and the surrounding oceanic crust. |
South American Plate | A tectonic plate division of the lithosphere that includes the continental crust of South America and the oceanic crust extending to the Mid-Atlantic ridge. |
Indo-Australian Plate | A tectonic plate division of the lithosphere that includes the continental crust of India and Australia and the surrounding oceanic crust. |
Pacific Plate | A tectonic plate division of the lithosphere that is composed entirely of oceanic crust and lies beneath the Pacific Ocean. |
Antarctic Plate | A tectonic plate division of the lithosphere that includes the continental crust of Antarctica and the surrounding oceanic crust. |
Density of Plates | The amount of matter in a given space or volume; oceanic crust is thinner, but denser than continental crust. |
Crustal Rock Material | Crust can be either oceanic, which is thin and dense, or continental, which is thick and less dense. |
Plate Boundary | The place where two different plates have contact. |
Convergent Boundary | Occurs when two tectonic plates move toward each other and collide. |
Subduction | The process in which a denser plate is pushed downward beneath a less dense plate when plates converge; occurs at continental to oceanic boundaries and oceanic to oceanic boundaries. |
Volcanic Eruptions | Events in which molten rock spews out from the mantle to the surface of Earth as ash, lava, and gases; major geological events that occur when a dense plate subducts below a less dense plate. |
Mountain Building | Major geological event that occurs when continental plates of equal density converge, resulting in mountain chains. |
Divergent Boundary | Occurs when two tectonic plates move away from each other. |
Spreading Ridges | Ridges formed from new crustal material at diverging oceanic plate boundaries. |
Ocean Basin | An area of oceanic crust covered by seawater and surrounded by areas of continental crust. |
Transform Boundary | Occurs when two tectonic plates slide past each other. |
Earthquakes | Major geological events that occur when plates shift suddenly and release stored energy; frequent occurrences along all types of plate boundaries. |
Geological Events | Ecological damage of a direct geologic nature, such as volcanic eruptions and earthquakes |
Plate Tectonics | A theory that Earth’s lithosphere (the crust and upper mantle) is divided into a number of large, plate-like sections that move as distinct masses |