- The discovery of a substantial “gravity hole” in the Indian Ocean, where the gravitational attraction is noticeably reduced, is one curious phenomenon recently observed.
- Recent study has given light on the potential causes of this phenomenon.
What is a Gravity Hole?
- A “gravity hole” is a location on Earth where the gravitational attraction is much weaker than in surrounding areas or the global average.
- It is distinguished by a dip or low gravity anomaly.
- Because of the decreased gravitational force acting on the water in such places, the sea level may be lower than average.
- This word is frequently used to characterise specific locales, such as the Indian Ocean geoid low (IOGL), where the gravitational attraction is significantly reduced in comparison to surrounding regions.
- Gravity holes can have a variety of reasons, including changes in the Earth’s mass distribution or underlying geological characteristics.
What exactly is the Indian Ocean Geoid Low (IOGL)?
- It is around 1,200 km southwest of India’s southernmost tip.
- IOGL refers to an area in the Indian Ocean where the sea level is approximately 106 metres lower than the worldwide average.
- Investigating the Root Causes of IOGL
Finding the Anomaly:
- During a survey in 1948, geophysicist Felix Andries Vening Meinesz discovered the IOGL. It has since been validated by ship-based investigations and satellite observations.
- The Indian Institute of Science developed computer-simulated models spanning 140 million years to test the Ancient Ocean Hypothesis. They uncovered the remains of an ancient ocean 965 kilometres into the Earth’s crust, directly beneath Africa.
- The models indicated molten rock jets beneath Africa, which could be triggered by tectonic plates subducting into the mantle. These plumes are thought to have contributed to the IOGL.
- Possible origins: According to the researchers, the IOGL is made up of slabs from the Tethys Sea, a long-lost sea that sank to the planet’s depths millions of years ago. The African Large Low Shear Velocity Province is thought to have been disturbed by the Tethys Sea, which previously divided the supercontinents of Gondwana and Laurasia.
Source: https://m.timesofindia.com/etimes/trending/theres-a-giant-gravity-hole-in-indian-ocean-and-scientists-have-finally-figured-out-how-it-was-formed/articleshow/101515305.cms