HONG KONG: For the first time ever, scientists exploring the ocean floor discovered what happened when a tectonic plate gets pushed under another. An expedition team drilled into the Pacific Ocean floor, and noticed distinctive rocks formed when the Pacific plate turned and plunged under the Philippine Sea Plate nearly 50 million years ago.
Professor Richard Arculus, study leader from the The Australian National University (ANU), said, “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. But we never knew what started the scrum collapsing.”
The new knowledge will assist scientists in comprehending the formations of volcanoes and earthquakes where the Earth’s plates crash and are pushed under one another.
The research team examined the sea floor in 4,700 meters of water in the Amami Sankaku Basin of the north-western Pacific Ocean, which is near the Izu-Bonin-Mariana Trench. It forms the deepest parts of the oceans. While drilling, the team found rock types in volcanoes and rifts that were made as a plate was settled under another in a process called subduction.