Plate tectonics
Generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago.
- Plate tectonics500 related topics
Fault (geology)
Planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements.
Planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements.
Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults.
Subduction
Geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries.
Geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries.
Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the heavier plate dives beneath the second plate and sinks into the mantle.
Asthenosphere
Mechanically weak and ductile region of the upper mantle of Earth.
Mechanically weak and ductile region of the upper mantle of Earth.
The asthenosphere is a part of the upper mantle just below the lithosphere that is involved in plate tectonic movement and isostatic adjustments.
Scientific theory
Explanation of an aspect of the natural world and universe that has been repeatedly tested and corroborated in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results.
Explanation of an aspect of the natural world and universe that has been repeatedly tested and corroborated in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results.
These qualities are certainly true of such established theories as special and general relativity, quantum mechanics, plate tectonics, the modern evolutionary synthesis, etc.
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a divergent or constructive plate boundary) located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world.
Upper mantle (Earth)
Very thick layer of rock inside the planet, which begins just beneath the crust and ends at the top of the lower mantle at 670 km. Temperatures range from approximately 200 C at the upper boundary with the crust to approximately 900 C at the boundary with the lower mantle.
Very thick layer of rock inside the planet, which begins just beneath the crust and ends at the top of the lower mantle at 670 km. Temperatures range from approximately 200 C at the upper boundary with the crust to approximately 900 C at the boundary with the lower mantle.
However, when large forces are applied to the uppermost mantle, it can become weaker, and this effect is thought to be important in allowing the formation of tectonic plate boundaries.
Continental drift
Hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed.
Hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed.
The idea of continental drift has been subsumed into the science of plate tectonics, which studies the movement of the continents as they ride on plates of the Earth's lithosphere.
Crust (geology)
Outermost solid shell of a rocky planet, dwarf planet, or natural satellite.
Outermost solid shell of a rocky planet, dwarf planet, or natural satellite.
There is no evidence of plate tectonics.