Most Costa Rican residents realize that the country rides on two tectonic plates. The Coco is forcing its way beneath the lighter Caribbean plate. The results include earthquakes and also the country’s majestic volcanoes.
Less well known is why the plates are in motion. A major scientific expedition offshore drilled into the Coco plate in May in an effort to answer some of these questions. Scientists know that the Caribbean plate was propelled, in part, by volcanic activity in the mid-Atlantic.
Now researchers in California have identified what they think is another force that drives the movement of plates. They are at the Scripps Institution of Oceanography at the University of California, San Diego.
Scripps scientists Steve Cande and Dave Stegman report that the new force that drives plate tectonics are plumes of hot magma pushing up from Earth’s deep interior, said the university. Their research was published in the Wednesday issue of the journal Nature.
Using analytical methods to track plate motions through Earth’s history, Cande and Stegman’s research provides evidence that such mantle plume hot spots, which can last for tens of millions of years and are active today at locations such as Hawaii, Iceland and the Galapagos, may work as an additional tectonic driver, along with push-pull forces, said a university release..
The pair identified a hot spot that created Réunion island near Madagascar as a driving force in moving the Indian subcontinent northwards. That was 70 million years ago.