Scientists identify mysterious link between Pacific’s largest underwater volcanoes

Ancient origins connected

A study has confirmed that two of the Pacific Ocean’s largest volcanic structures, the Ontong Java Plateau and the Louisville hotspot, share a common geological origin. The discovery led by scientists from the University of Maryland and the University of Hawaii reshapes long-standing theories about the evolution of volcanic systems in the Pacific region.

Resolving a longstanding mystery

The Ontong Java Plateau, a vast underwater volcanic platform north of the Solomon Islands, is one of the planet’s largest volcanic features. For decades, geologists debated its origins. Meanwhile, the Louisville hotspot, located in the southern Pacific, forms a chain of submarine volcanoes. Though a link was suspected, conclusive evidence had remained elusive.

Tracking a lost trail

Much of the difficulty lay in missing geological evidence. Parts of the ancient Louisville hotspot trail had been subducted, pushed beneath the Earth’s crust, making direct study impossible. However, researchers recently identified volcanic remnants near Samoa that provided the missing connection.

Unexpected discoveries near Samoa

While sampling underwater mountains near Samoa, the team found much older volcanic structures than expected. These samples contained geochemical and age signatures consistent with early activity from the Louisville hotspot, revealing a hidden section of the hotspot’s path.

Footprints of a shared source

This evidence shows that the same deep-mantle plume responsible for the Louisville Ridge also played a role in forming the Ontong Java Plateau around 120 million years ago. The full study was published in the journal Nature.

Rewriting pacific plate history

The discovery has led to a revision of models describing Pacific plate movement. By identifying this connection, scientists are gaining a more cohesive view of volcanic evolution across the ocean basin.

Broader implications for volcanology

Beyond reconstructing geological history, the findings could help researchers better understand volcanic island formation and hazard assessment across the Pacific. The updated models may also be applied to investigate other enigmatic volcanic regions.