Potsdam (Germany) : India is the fastest-moving continent in the Earth’s history, thanks to a huge bubble of hot stone underneath it, German and Indian scientists said Wednesday.
The Himalayas, the world’s highest mountains, were thrown up when India, sliding along at the unusually high speed of 20 cm per year, crashed 50 million years ago into the tectonic plate on which Europe and Asia sit.
A closer study of the collision was published Wednesday in the British science journal Nature.
A team at the Geo-Research Centre in Potsdam near Berlin and the National Geophysical Research Institute of India found the reason for the rapid move: the magma had melted away half of the Indian continent from below.
That made it lighter and able to move faster.
German scientist Rainer Kind led development of a new method to discover how the ancient supercontinent Gondwana broke apart. The Indian plate was part of Gondwana until 140 million years ago.
The scientists noticed that the Indian plate is only about 100 km thick, just half the height of other remnants of Gondwana broken away by the bubble of magma.
“This volcano melted away the lower half of the Indian subcontinent, and that is why India could be pushed away so quickly,” a scientist explained.
Before the break-up there were just two continents on the planet, Laurentia in the northern hemisphere and Gondwana in the southern. Today’s Africa, South America, southern India and Antarctica are all Gondwana remnants.
The tectonic plates are still moving today, with earthquakes and volcanoes the most visible effects. http://dx.doi.org/10.1038/nature06214