Scientists have potentially solved the mystery of a deep “gravity hole” in the Indian Ocean, where Earth’s gravitational pull is weaker than in other parts of the planet. Known as the Indian Ocean geoid low (IOGL), this depression is located 746 miles southwest of India and covers an area of 1.2 million square miles. The gravity in this region is so weak that the sea level over the hole is 348 feet lower than the global average. The origin of this anomaly has puzzled scientists since its discovery in 1948.
A recent study published in the journal Geophysical Research Letters suggests that the IOGL was caused by low-density magma that was pushed into the Indian Ocean by sinking slabs of an ancient ocean. The researchers used 19 computer models to simulate the motions of the mantle and tectonic plates in the region over a span of 140 million years. The models that best simulated the real geoid low shared a common feature: plumes of hot, low-density magma that rose up to displace higher-density material beneath the low, reducing the region’s mass and weakening its gravity.
These plumes originate from a disturbance 600 miles west under Africa, known as the “African blob.” This dense bubble of crystallized material inside Africa’s mantle is the size of a continent and 100 times taller than Mount Everest. The final pieces of the puzzle are remnants of seafloor from the ancient ocean of Tethys, called “Tethyan slabs.” The researchers propose that after the Indian plate broke off from Gondwana and collided with the Eurasian plate, it passed over the Tethys plate, subducting it and pushing it under the Indian plate. As the Tethyan plates sank deeper into the lower mantle, they displaced some of the African blob’s trapped magma, forming the plumes responsible for the gravity hole.
To confirm these predictions, scientists will need to analyze earthquake data collected from around the geoid low to uncover the existence of the plumes. The discovery of these plumes would provide further insight into the origins of the gravity hole in the Indian Ocean.
What further analysis is needed to provide additional evidence and support the researchers’ explanation for the formation of the Indian Ocean geoid low
Scientists may have finally cracked the case of the mysterious “gravity hole” in the Indian Ocean. This peculiar depression, known as the Indian Ocean geoid low (IOGL), has been a puzzle since it was discovered in 1948. Located 746 miles southwest of India, the IOGL covers a vast area of 1.2 million square miles and experiences a much weaker gravitational pull compared to other parts of the planet. In fact, the sea level over this gravitational anomaly is approximately 348 feet lower than the global average.
A recent study published in the journal Geophysical Research Letters offers a potential explanation for this enigma. According to the researchers, the IOGL was formed by low-density magma being pushed into the Indian Ocean by sinking slabs of an ancient ocean. To investigate this hypothesis, the scientists employed 19 computer models to simulate the movements of the mantle and tectonic plates in the region over a span of 140 million years. The models that produced the most accurate representation of the real geoid low shared a common feature: plumes of hot, low-density magma rising up and displacing higher-density material beneath the low. This displacement reduced the region’s mass, resulting in the weakening of its gravity.
These magma plumes originate from a disturbance located 600 miles west under Africa, dubbed the “African blob.” This dense bubble of crystallized material within Africa’s mantle is colossal, spanning the size of a continent and towering 100 times higher than Mount Everest. Moreover, the final missing pieces of the puzzle are remnants of the seafloor from the ancient ocean of Tethys, referred to as “Tethyan slabs.” The researchers propose that after the Indian plate separated from Gondwana and collided with the Eurasian plate, it passed over the Tethys plate. As the Indian plate subducted the Tethys plate, pushing it under itself, the Tethyan slabs sank deeper into the lower mantle. This sinking motion displaced some of the trapped magma within the African blob, ultimately leading to the formation of the plumes responsible for the gravity hole.
Confirmation of these predictions relies on further analysis of earthquake data collected from the area surrounding the geoid low. Detecting the presence of the plumes through earthquake data would offer additional insights into the origins of the gravity hole in the Indian Ocean. With the potential solution to this long-standing mystery within reach, scientists eagerly await more evidence to support their findings.
This article sheds light on the enigma behind the Indian Ocean’s gravity hole, unraveling its origins with compelling evidence. A fascinating read that leaves me in awe of Mother Nature’s mysterious wonders.
This article offers a fascinating glimpse into the intriguing discovery of the enigmatic gravity hole lurking beneath the Indian Ocean. A significant breakthrough in science, these newfound origins shed light on a mysterious natural phenomenon that captivates our imaginations.