Hidden ‘blobs’ deep beneath Earth may trigger massive volcanic eruptions

Hidden ‘Blobs’ Deep Beneath Earth May Trigger Massive Volcanic Eruptions (Image: Canva)

They lie far below our feet—silent, shifting, and unseen. But new research suggests these deep Earth structures could hold the key to some of the most powerful volcanic eruptions in history.

Scientists have long wondered what triggers major volcanic events. Now, researchers say they have found a link between surface eruptions and mysterious structures deep in Earth’s lower mantle.

These formations, nicknamed "BLOBS," stretch across the mantle layer around 3,000 kilometres beneath the surface. They sit beneath Africa and the Pacific Ocean and could influence where and when volcanoes erupt above.

Volcanologist Annalise Cucchiaro from the University of Wollongong led the new study. Her team used data from three sources to show a strong link between BLOBS and large volcanic eruptions from around 300 million years ago.

These BLOBS are thought to shift and fold like tectonic plates. They may also guide the rising of hot rock plumes, which act like highways of magma leading to the surface. When these plumes break through, they can spark eruptions powerful enough to reshape the planet.

3D models show plume and BLOB structures beneath the African (a) and Pacific (b) hemispheres as they appeared 60 million years ago. (Image: Cucchiaro et al., Communications Earth & Environment, 2025)

Cucchiaro explained that BLOBS are closely tied to mantle plumes. These rising columns of heat and rock are behind many historic eruptions. They also play a role in surface creation and destruction.

Her team simulated how BLOBS may have moved one billion years ago. Their models showed that plumes often tilted as they rose, sometimes erupting directly above or slightly beside the BLOBS.

Those eruption sites matched real volcanic hotspots from geological records. This finding helped confirm that the simulations were on the right track.

Geoscientist Nicholas Flament, a co-author of the study, said their work shows a close connection between deep mantle plumes and surface volcanic activity. It also suggests that BLOBS are not fixed but constantly shifting.

The study opens up new ways to understand Earth’s violent past. It could also help predict future volcanic activity and identify sites rich in valuable minerals.

Knowing the paths magma might take can aid in locating kimberlite and diamonds. It may also guide future searches for energy-critical minerals buried deep underground.

“This research cracks open one of the big questions,” Flament said. “Are the BLOBS stationary or moving, and how do they link to giant eruptions?”

The findings were published in Communications Earth & Environment. Scientists hope this work will help uncover more of the hidden forces shaping our planet from below.