What are the theories of plate tectonics, and there are several major plates in the theory of plate

In 1910, the German meteorologist Alfred Lothar Wegener (1880-1930) stumbled upon a striking similarity in the contours of the Atlantic Ocean. After research and inference, he published "The Formation of Continents" in 1912 and "The Origin of Land and Sea" in 1915, and put forward the theory of continental drift. The theory holds that in the late Paleozoic Era (about 300 million years ago) there was a "pan-continent" on the earth, and correspondingly there was also a "pan-ocean".

Later, under the action of the centrifugal force of the earth's rotation and the gravitational force of celestial bodies, the granite layers of the pancontinent separated and drifted on the basalt layers distributed throughout the earth's crust, gradually forming a modern distribution of land and sea.

In 1968, the French geologist Le Pichon, Mackenzie, Morgan and others proposed a new theory of continental drift, which is a specific extension of the theory of seafloor expansion.

Plate tectonics, also known as global tectonics. The term "plates" refers to lithospheric plates, including the entire crust and the top of the upper mantle below the Moho surface, that is, the top of the mantle above the crust and asthenosphere. The new global tectonic theory holds that large-scale horizontal movements have occurred and continue to occur in both continental and oceanic crusts.

However, this horizontal movement does not occur between the silicon-aluminum and silicon-magnesium layers, as the continental drift theory envisions, but rather the lithospheric plates move like a conveyor belt along the entire mantle asthenosphere, and the continents are only "passengers" on the conveyor belt.

The theory of plate tectonics has six major plates.

Through decades of rapid development, the theory of plate megatectonics has completely shaken the traditional geological theory. With the development and improvement of theories, these assumptions have undergone a certain degree of revision and expansion, and this evolution history is the condensation of the development of the geoscience community over the years. At the same time, plate tectonics itself has many shortcomings and characteristics that are difficult to verify.

The initial simple but strict assumptions of plate tectonics theory were that both the rigid and elastic lithosphere were plastic asthenospheres, that the lithosphere was divided into a few large plates, that there were three interactions between these plates in strict accordance with Euler's theorem, that the subduction and expansion of the plates were all mutually compensated in order to keep the volume of the earth constant, and that the direct condition for plate movement was convection in the asthenosphere.

Plate tectonics theory is a tectonic theory formed in the late 60s, which is a further development of the theory of continental drift and seafloor expansion. It is a summary and summary of the global crustal activity pattern on the basis of a large number of recent research results in marine geology, seabed geomorphology and geophysics.

Plate tectonics is a new global tectonic theory proposed in the 60s of the 20th century. The theory of plate tectonics was developed on the basis of the theory of continental drift and the theory of seafloor expansion.

The theory of plate tectonics holds that the basic tectonic unit of the lithosphere is the plate; The plate boundaries are mid-ocean ridges, conversion faults, subduction zones, and ground sutures; The basic cause of global crustal tectonic movement is the interaction of these plates; The plate is very strong, and the edge of the plate is where the tectonic movement is most intense, and the main deformation is in its edge part.

The difference between plate movement and continental drift:

1. Wegener et al. only contain the continental silicon-aluminum layer on the mainland; In the plate theory, lithospheric plates contain the lithosphere (lithospheric mantle) above the earth's crust and asthenosphere.

2. Wegener and others regard the continent as an active unit, while the continent is passive in the plate theory. The continental drift theory holds that the continents drift through the subcrustal silicon-magnesium layer; The Vertical Plate Doctrine introduces the concept of a passive continent like being carried on a conveyor belt. Due to their low density in composition, they are usually more buoyant and can escape the fate of being reduced, becoming a stable passive buoyancy block on the conveyor belt.

3. Wegener et al. regard the continental silicon-aluminum layer as something completely different from the silicon-magnesium layer of the earth's mantle; The plate theory holds that the land is a chemical product of the mantle differentiation and floating, and the land is linked to the part of the mantle below.

The theory of plate tectonics was proposed on the basis of the theory of continental drift and the theory of seafloor expansion. After long-term research, geologists put forward the theory of plate tectonics, believing that the world is composed of six plates, generally speaking, the interior of the plate is relatively stable, the plate and the plate junction zone, the earth's crust is more active, and there are many volcanoes, ** The names of the six plates are the Eurasian plate, the African plate, the Indian plate, the Pacific plate, the American plate, and the Antarctic plate The plate movement mode is collision, extrusion, and tension and stretching Among the six major plates, the Pacific plate is almost all oceanic, and the rest of the plates include both land. It also includes the ocean Therefore, the answer is: the world is composed of six major plates, generally speaking, the interior of the plate is relatively stable, the plate and the plate junction zone, the earth's crust is more active, and there are many volcanoes, ** The names of the six plates are the Eurasian plate, the African plate, the Indian Ocean plate, the Pacific plate, the American plate, and the Antarctic plate The plate movement mode is collision, extrusion and tension and stretching Among the six major plates, the Pacific plate is almost all oceanic, and the rest of the plates include both land and ocean.