The remnants of an ancient ocean could be causing a 'gravity hole' in the Indian Ocean


A so-called "gravity hole" in the Indian Ocean, where the gravitational pull is weaker than other places on Earth, could be the result of magma plumes from deep within the planet, scientists recently discovered, according to findings published in the journal Geophysical Research Letters. Researchers were previously unsure as to why the phenomenon existed.
"The Earth is basically a lumpy potato" and not a sphere, study coauthor Attreyee Ghosh told CNN. Therefore, gravity is distributed unevenly around the planet. "If you pour water on the surface of the Earth, the level that the water takes is called a geoid," determined by density differences under the surface of the Earth. The "gravity hole" in the Indian Ocean is the "biggest low" in the geoid, Ghosh continued.
In order to explain the anomaly, researchers used computer models to study plate tectonics and determine how the region formed historically. They found that the gravity discrepancy goes back to the "separation of Gondwana, the supercontinent at the origin of Africa, Australia and India," Insider explained. "As India separated from Africa and smashed into the European plate, the ocean that used to be there, called Tethys, was split apart and squished between the continental plates." The shifting of the continents over time eliminated the Tethys Ocean, and the oceanic plate began to sink deeper into the Earth, causing lower gravity. The movement has also slowly melted the Earth's mantle, releasing plumes of magma, similar to how volcanoes form.
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
As of now, researchers are not certain whether the gravity hole will remain or whether it will disappear in the future. Further research is also required to confirm the existence of the plumes, Himangshu Paul, a scientist at the National Geophysical Research Institute in India, told New Scientist.
Sign up for Today's Best Articles in your inbox
A free daily email with the biggest news stories of the day – and the best features from TheWeek.com
Devika Rao has worked as a staff writer at The Week since 2022, covering science, the environment, climate and business. She previously worked as a policy associate for a nonprofit organization advocating for environmental action from a business perspective.
-
Retribution: Trump calls for prosecution of critics
Feature Trump targets former officials who spoke out against him, sending a warning to future whistleblowers
By The Week US
-
Why does the U.S. need China's rare earth metals?
Today's Big Question Beijing has a 'near monopoly' on tech's raw materials
By Joel Mathis, The Week US
-
When did divorce begin?
The Explaine Couples have always split up, but the institution has undergone major changes over the years
By David Faris
-
Scientists find hint of alien life on distant world
Speed Read NASA's James Webb Space Telescope has detected a possible signature of life on planet K2-18b
By Peter Weber, The Week US
-
Katy Perry, Gayle King visit space on Bezos rocket
Speed Read Six well-known women went into lower orbit for 11 minutes
By Peter Weber, The Week US
-
Scientists map miles of wiring in mouse brain
Speed Read Researchers have created the 'largest and most detailed wiring diagram of a mammalian brain to date,' said Nature
By Peter Weber, The Week US
-
Scientists genetically revive extinct 'dire wolves'
Speed Read A 'de-extinction' company has revived the species made popular by HBO's 'Game of Thrones'
By Peter Weber, The Week US
-
Toxic algae could be causing sea lions to attack
In the Spotlight A particular algae is known to make animals more aggressive
By Justin Klawans, The Week US
-
Dark energy may not doom the universe, data suggests
Speed Read The dark energy pushing the universe apart appears to be weakening
By Peter Weber, The Week US
-
Pharaoh's tomb discovered for first time in 100 years
Speed Read This is the first burial chamber of a pharaoh unearthed since Tutankhamun in 1922
By Peter Weber, The Week US
-
Scientists report optimal method to boil an egg
Speed Read It takes two temperatures of water to achieve and no fancy gadgets
By Peter Weber, The Week US