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Earth's surface dynamics HTML5
The Earth’s surface is active and continually changing. A simplifed global view illustrates the dynamics of Earth’s interior.
The mantle is a large energy producing envelope (radioactive elements are present), like a nuclear power plant! The main implications are:
It is currently taught that:
- Mantle convection: mantle convection loops are responsible for movement of lithospheric plates. Subduction is the result.
- Subduction: This is the disappearance of the seafloor at the subduction zones level. That is, the lithospheric plate falls and disappears into the asthenosphere.
However, experts now know that the phenomenon is reversed:
- Subduction: This is the disappearance of the seafloor at subduction zone levels. That is, the lithospheric plate falls and disappears into the asthenosphere. It is of major importance in tectonics because it is driving the movement of the plates .
- Mantle convection: This is the complementary phenomenon that compensates for the loss of material by subduction. It is originally under the dorsal surface and deeper under the hot spots.
Note: Some scale ratios are not respected.
- To build a model of plate tectonics.
- To link mantle convection and subduction.
- To understand the key role of subduction tectonics.