In wonderful, unexpected ways, Earth still manages to surprise scientists. A team of researchers from the University of Maryland in the U.S. has discovered a large structure made up of thick material near the Earth's core.
That's roughly 3,000 kilometers (1,864 miles) beneath your feet. The team used a machine-learning algorithm to probe this mysterious phenomenon occurring deep within our Earth.
Their findings were published in Science on Friday.
One of these big anomalies is located far below the Marquesas Islands in the Pacific Ocean, and has never been detected before. Another one of them is far beneath the Hawaiian Islands, also in the Pacific, and this one is much larger than was previously believed.
The team, led by Doyeon Kim, a seismologist and postdoctoral fellow at the University of Maryland, used seismograms from hundreds of different earthquakes between 1990 and 2018 and put them into a machine learning algorithm called Sequencer.
"This study is very special because, for the first time, we get to systematically look at such a large dataset that actually covers more or less the entire Pacific basin," Kim said in a call to Vice.
After running thousands of seismograms through Sequencer, Kim and his team discovered that the strongest post cursor signals were found beneath the Marquesas and Hawai'i's islands. This proves that there exist two "mega-ULVZs" zones that span around 1,000 kilometers (621 miles) or more.
Mega-ULVZs are huge structures that are made up of exotic materials that date back to the times before Earth had a Moon. "This is very interesting because this might indicate that mega-ULVZs are special and may host primitive geochemical signatures that have been relatively unmixed since early Earth history," Kim explained.
The team plans on continuing its research deep beneath the Earth's surface to develop a method of peering into Earth and find out what else is down there. The hope is to also look at what lies beneath the Atlantic Ocean.
"We’re hoping that Sequencer will be able to basically let us use all of these diverse datasets and bring them together to look for these lower mantle structures systematically," Kim concluded. "That is our vision going forward, to answer more questions about the lower mantle in general."