Researchers from the Indian Institute of Science recently investigated the enigmatic ‘gravity hole’ in the Indian Ocean. They uncovered its formation, which is linked to ancient ocean movements and hot magma plumes. The ‘gravity hole,’ known as the Indian Ocean Geoid Low (IOGL), spans approximately three million square kilometers and is characterized by low gravity and a sea level over 106 meters lower than the global average.
The scientists found that the non-uniform gravitational field of the Earth in this unique region is a result of variations in density and mass distribution. Through their study, led by Debanjan Pal and Attreyee Ghosh, they discovered a significant event from the Earth’s past when an ancient ocean descended beneath the crust and interacted with molten rock nearly 30 million years ago.
Computer simulations revealed that plumes of hot, low-density magma played a crucial role in the formation of the gravity hole, with the first plume emerging about 20 million years ago and subsequently intensifying the anomaly. The researchers also acknowledged the contribution of lower mantle Tethys slabs in forming the geoid low.
In summary, the ‘gravity hole’ in the Indian Ocean is caused by variations in density and mass distribution, resulting in irregularities in the Earth’s gravitational field, which is further influenced by the interaction of ancient ocean movements and hot magma plumes.
