Scientists reveal the reason behind huge gravity hole in middle of Indian Ocean. Read here

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Business Insider reveals that the gravity hole which was known as the Indian Ocean geoid low was possibly due to plumes of molten rock which was rising from the remains of an ancient hotbed. The variation of gravitational forces over the surface of the Earth is not news. A dense continent can have more gravitational force than a zone where the crust is thinner.

But, the variation in gravity in the Indian Ocean puzzled scientists for decades. "I think what people generally assume is that there must be something low density underneath that's causing that," a geodynamics researcher at GFZ German Research Centre of Geosciences, told Business Insider. "But in that paper, they have actually a different theory," he said.

Geophysicist Attreyee Ghosh and doctoral student Debanjan Pal from the Indian Institute of Science and Research, Bangalore expanded the scope of their research and plotted 19 different scenarios over a period of 140 million years. The computer-generated scenarios observed the movement of tectonic plates around the gravity hole. They discovered that the possible reason for the gravity hole is the plumes of magma.

"It's something you could have thought of before, you just wouldn't think of it because you tend to think there must be something underneath," said Steinberger, who was not involved in the study. The phenomena might have originated 120 million years ago when the supercontinent Gondwana land separated. As the Indian plate separated from the African plate, it smashed into the European plate and the ocean called Tethys was squeezed between the continental plates.