Researchers from the Australian National University have released a new study detailing the results of their expeditions drilling into the Pacific ocean floor, where they discovered what happens after one tectonic plate is forced underneath another, according to the press release. Their findings stem from the discovery of rocks that were formed from a Pacific tectonic plate that changed direction and made its way under the Philippine Sea Plate approximately 50 million years ago.
"It's a bit like a rugby scrum, with two rows of forwards pushing on each other. Then one side goes down and the other side goes over the top." said Richard Arculus, lead author of the study. "But we never knew what started the scrum collapsing."
The team focused their efforts on the sea floor in the waters of the Amami Sankaku Basin located in the north-western Pacific Ocean. This area is located near the Izu-Bonin-Mariana Trench, which is connected to the deepest parts of the Earth's oceans.
Approximately 1,600 meters into the floor is where the research team discovered the unique rock types that were remnants of subduction, the process of one plate being forced under another.
"We found rocks low in titanium, but high in scandium and vanadium, so the Earth's mantle overlying the subducting plate must have been around 1,300 degrees Celsius and perhaps 150 degrees hotter than we expected to find," said Arculus.
The new findings will help scientists in their quest to understand the details of the earthquake and volcano formation that takes place when the collision of Earth's plates forces on underneath another. Furthermore, they could also help scientists better understand the formation of copper and gold deposits that are typically found around sites of plate subduction.