Scientists recently made an incredible discovery deep beneath the Pacific Ocean near Easter Island. They found what they described as a “fossilized fingerprint” of a chunk of seafloor that sank into Earth’s mantle about 250 million years ago. This finding sheds light on a mysterious gap in the Earth’s crust.
This sunken slab of seafloor is now lodged between the upper and lower mantle in a region known as the mantle transition zone. This zone, located between 255 and 410 miles beneath the Earth’s surface, plays a crucial role in the planet’s geological processes.
Using seismic waves, researchers were able to create a digital cross-section of the Earth’s crust and mantle beneath the East Pacific Rise. This revealed a thickened portion of the mantle transition zone near Easter Island, marking the path of the ancient seafloor that subducted into the Earth.
Typically, when tectonic plates collide, one plate dives beneath the other in a process known as subduction. The material from the subducting plate usually melts in the mantle due to high temperatures. However, this particular slab managed to avoid complete destruction, providing researchers with a unique opportunity to study Earth’s deep interior.
The slab’s slow movement through the mantle suggests that the mantle transition zone can act as a barrier, slowing down the sinking material. This discovery could also explain a gap in the lower mantle known as the Pacific Large Low Shear Velocity Province.
This finding not only offers new insights into Earth’s geological history but also opens up possibilities for further exploration of plate tectonics. Researchers believe that there are more ancient structures waiting to be uncovered in the Earth’s deep interior, each holding valuable information about our planet’s complex past and potentially leading to a better understanding of other planets.
The study published in the journal Science Advances marks the beginning of a new chapter in Earth science, where ancient structures hidden deep within the planet may hold the key to unraveling its mysteries.
