Why is there a 'gravity hole' in the Indian Ocean, exactly?

The enigmatic "gravity hole" in the Indian Ocean may have an explanation, according to researchers from the Indian Institute of Science.

Although it is simple to picture the Earth as a flawless sphere with constant gravity, that is far from the truth. Contrary to popular belief, our world bulges near the equator and is flat at the poles. Its gravity isn't constant throughout, either. For instance, researchers have finally discovered why there is a significant "gravity hole" in the Indian Ocean.

It may be easy to imagine the Earth as a perfect sphere with constant gravity, but that is far from the reality. Contrary to common assumption, our earth is flat at the poles and bulges at the equator. Even its gravity fluctuates over time. For instance, scientists have now determined the cause of the large "gravity hole" in the Indian Ocean.

The Indian Ocean Geoid Low (IOGL) was first identified in 1948 by Dutch geophysicist Felix Andries Vening Meinesz during a study of the ocean. Since then, it has been supported by more ship-based research and satellite-based observations. However, scientists haven't really been able to establish definitively why it occurs. Up till this point.