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The Vine–Matthews–Morley hypothesis, also known as the Morley–Vine–Matthews hypothesis, was the first key scientific test of the seafloor spreading theory of continental drift and plate tectonics. Its key impact was that it allowed the rates of plate motions at mid-ocean ridges to be computed.
The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, which ride on the fluid-like solid the asthenosphere. Plate motions range from 10 to 40 millimetres per year (0.4 to 1.6 in/year) at the Mid-Atlantic Ridge (about as fast as fingernails grow), to about 160 millimetres per year (6.3 in ...
Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago.
The key modification to the basic plate-tectonic model here is a relaxation of the assumption that plates are rigid. This implies that lithospheric extension occurs not only at spreading plate boundaries but throughout plate interiors, a phenomenon that is well supported both theoretically and empirically. [12] [13]
Frederick John Vine FRS (17 June 1939 – 21 June 2024) was an English marine geologist and geophysicist.He made key contributions to the theory of plate tectonics, helping to show that the seafloor spreads from mid-ocean ridges with a symmetrical pattern of magnetic reversals in the basalt rocks on either side.
In passive rifting, driven by plate tectonics, the crust and lithosphere extend as a result of plate boundary forces such as slab pull. [10] Far field stresses thin the crust and lithospheric mantle, and hot asthenospheric mantle passively enters the thinned area. [10] The upwelling of asthenosphere is not involved in the actual rifting process.
Tectonophysics is concerned with movements in the Earth's crust and deformations over scales from meters to thousands of kilometers. [2] These govern processes on local and regional scales and at structural boundaries, such as the destruction of continental crust (e.g. gravitational instability) and oceanic crust (e.g. subduction), convection in the Earth's mantle (availability of melts), the ...
Indo-Australian plate – Major tectonic plate formed by the fusion of the Indian and Australian plates (sometimes considered to be two separate tectonic plates) – 58,900,000 km 2 (22,700,000 sq mi) Australian plate – Major tectonic plate separated from Indo-Australian plate about 3 million years ago – 47,000,000 km 2 (18,000,000 sq mi)