Scientists have found that one of the most extreme volcanic events in Earth’s history did more than create a huge underwater plateau. According to ScienceDaily, it also changed the structure and chemistry of the oceanic plate below it.
The research focused on the Ontong Java Plateau, the world’s largest oceanic plateau in the western Pacific Ocean. The plateau formed about 110 to 120 million years ago during what is considered the largest volcanic outpouring known on Earth.
Using seismic waves, a team led by Lecturer Azusa Shito of Okayama University of Science examined the deep structure beneath the plateau. Their results, published in Geophysical Research Letters, suggest that magma moved through the existing plate in many pathways, creating vertical intrusions called dikes alongside horizontal layers.
The scientists also found that seismic waves traveled unusually slowly beneath the plateau. They said that structure alone could not explain the readings and proposed that magma from a thermochemical plume chemically altered the plate as well, a process known as refertilization.
The study suggests that massive volcanic events can fracture oceanic plates, build extensive dike networks, and change the chemistry of the rock itself, offering new insight into how large volcanic provinces reshape Earth’s interior.
