Earths biggest volcanic event transformed an entire oceanic plate

Seismic waves have revealed that the oceanic plate beneath the Ontong Java Plateau was dramatically transformed by the colossal volcanic activity that created it more than 100 million years ago. Researchers found a complex structure of horizontal layers cut through by vast swarms of vertical magma channels, along with unusually slow seismic waves suggesting that deep-rising magma chemically altered the plate itself.