Researchers from Bengaluru’s Indian Institute of Science have made a breakthrough discovery of the ‘gravity hole’ in the Indian Ocean which is a region where the gravitational pull is significantly lower than the surrounding, creating a dip in the Earth’s Gravity Field.
What in News?
The gravitational force varies depending on the mass distribution of crust, mantle and core as the shape and gravity are not uniform across the Earth’s surface instead it is slightly flattened at the poles and wider at the equator.
One of the most striking examples of the variation in the gravitational force is the Indian Ocean Geoid Low (IOGL).
The IOGL was first detected by a Dutch geophysicist Felix Andries Vening Meinesz in 1948 during a ship-based survey.
Indian Ocean Geoid Low (IOGL) is a huge depression in the sea level that is about 106 metres lower than the global average.
The cause of IOGL anomaly remained a mystery for decades and now a new study revealed the reason behind this.
Gravity Hole
Gravity hole is an area where the gravitational pull is lighter in comparison to the other surroundings.
Gravity holes happen due to the variation in density and mass distribution as the Earth’s Gravitational Force is not uniform.
Methodology
- Researchers from the Indian Institute of Science of Bengaluru– Debanjan Pal and Attreyee Ghosh explained their hypothesis about the origin of the gravitational anomaly.
- Researchers used computer-simulated models to reconstruct the geological history of the past 140 years. Through this they discovered the traced of the ancient ocean which was about 965km deep inside the earth’s crust below Africa.
- The computer-simulations showed that there were molten rocks plump under Africa, which could have been formed by the subduction of tectonic plates into the mantle.
- According to them, these plumps could be responsible for IOGL.
- Later they admitted new scientist as they have not any clear evidence to confirm the existence of plumes under the Indian Ocean.
- Scientists thought there are some other unknown factors that need to be investigated further.