¿Qué mueve las placas tectónicas?
- Carlos Fernández
- Pedro Alfaro
- Gabriel Gutiérrez Alonso
- Francisco M. Alonso Chaves
ISSN: 1132-9157
Year of publication: 2019
Volume: 27
Issue: 3
Pages: 238-245
Type: Article
More publications in: Enseñanza de las ciencias de la tierra: Revista de la Asociación Española para la Enseñanza de las Ciencias de la Tierra
Abstract
For several decades scientists have been working with the idea that tectonic plates are not passively carried by convection cells. They propose that the plates have a more protagonist role, being an active part of the Earth’s convection. On a planet like ours, with a heterogeneous geothermal gradient and an unequal distribution of densities in surface and at depth, gravitational forces are capable of displacing the tectonic plates. Among all these forces, the slab pull, associated with subduction zones, is the most important. The lithospheric plates move with a velocity that does not depend on their size, but on the percentage of oceanic and continental lithosphere, and on the type of boundaries (divergent, transform, convergent) that limit them. In this sense, the plates that are surrounded mainly by subduction zones (where they are the subducting plate), and have a greater percentage of oceanic lithosphere, are usually the fastest.