The collision between Eurasia and the Indian subcontinent, which created the world's highest mountain range, is slowing down, a new study has found.
As Earth's tectonic plates move across the planet's surface, the continents that sit atop them are carried along, sometimes smashing together for many millions of years at a time. As the continents mash against each other, their collision gradually slows.
New research suggests that this slowing may be the work of forces not within Earth's crust, as is generally thought, but deep underneath it.
Understanding the forces controlling the shifting tectonic plates can help shed light on the factors that drive earthquakes and volcanoes, as well as the origins and demise of mountains, oceanic trenches and continents.
Researcher Marin Clarkfocused on India's ongoing collision with Eurasia to gain more insight into these forces.
"The India/Eurasia collision is enormous — it's created the largest landform made in the last 500 million years or so: the Himalaya and the Tibetan Plateau together," said Clark, a geophysicist and geomorphologist at the University of Michigan, Ann Arbor. "The landform's so big, it affects the atmosphere."
Clark examined geological data from prior studies to analyze how India has moved northward in the last 67 million years. She also investigated the slowly changing height of the land in the collision region.
"The Himalaya and the Tibetan Plateau have grown as India's moved northward, like how a box would get taller if you squeezed it," Clark told OurAmazingPlanet.
Clark determined present rates through global positioning system measurements, and established past rates simply by comparing the size of the Tibetan Plateau with the speed at which India moved northward.