Earth's tectonic plates have doubled their speed: study

Earth's tectonic plates are moving faster now than at any point in the last 2 billion years, according to a new study.

Plate tectonics is driven by the formation and destruction of oceanic crust. This crust forms where plates move apart, allowing hot, light magma to rise from the mantle below and solidify.

The planet's inner heat which powers plate tectonics is ebbing away as Earth ages, and this was expected to slow plate motion.

A research last year by Martin Van Kranendonk at the University of New South Wales in Sydney, Australia, and colleagues measured elements concentrated by tectonic action in 3,200 rocks from around the world, and concluded that plate motion has been slowing for 1.2 billion years.

But now Kent Condie, a geochemist at the New Mexico Institute of Mining and Technology in Socorro and his colleagues have used a different approach and concluded that tectonic activity is actually increasing, 'New Scientist' reported.

They looked at how often new mountain belts form when tectonic plates collide with one another.

They then combined these measurements with magnetic data from volcanic rocks to work out at which latitude the rocks formed and how quickly the continents had moved. Both techniques showed plate motion has accelerated.

The average rate of continental collisions, and the average speed with which the continents change latitude, has doubled over the last 2 billion years, the study found.

"We expected to find that the average speed would be slowing down with time, but we didn't get that. Both speeds were going up. It was a surprise," said Condie.