Earth has a 'ghost plume' rising from deep within the planet's mantle up to the surface

Earth leaks roughly 47 terawatts of heat into space, a trickle compared with the Sun’s input yet vital for plate tectonics, volcanoes, and the magnetic field. This outward flow is usually thought to rise slowly through mantle convection, like steam seeping through thick soup.

A new study proposes that some of the heat takes express lanes known as mantle plume columns, a concept first drawn by W. Jason Morgan in 1971.

Now researchers report the first “ghost plume” with no evidence of surface volcanism, hiding beneath Oman’s eastern deserts. Lead author Simone Pilia of King Fahd University of Petroleum and Minerals analyzed thousands of earthquake signals and named the buried column the Dani plume after his son.

Oman’s mantle plume rises but does not erupt

Typical plumes reach the surface and build features like Hawaii or Yellowstone, but Oman shows no fresh lava fields. That absence makes the Dani plume a ghost: hot enough to soften rock, not hot enough to punch through a thick continental lid.

“The more we gathered evidence, the more we were convinced that it is a plume,” said Pilia. His team traced the column to a depth of at least 410 miles (660 kilometers), where seismic waves slowed in a neat cylinder about 125 miles (200 kilometers) wide. 

Independent checks found the mantle transition zone warped downward at a depth of 255 miles (410 kilometers) and lifted again at 410 miles (660 kilometers), giving a classic thermal fingerprint of rising material.

Earthquake waves reveal hidden mantle plume

The hunt relied on seismic tomography, Earth’s version of a CT scan, which turns quake vibrations into 3‑D velocity maps. A temperature rise of about 200 °F (93 °C) can drop shear‑wave speeds by roughly three percent.

In Oman, shear speeds fell by that amount inside the column, implying an excess temperature of roughly 200–500 °F (93–260 °C). That is warm enough to soften peridotite yet still below the melting threshold under 130‑mile‑thick (209-kilometer-thick) lithosphere.

Saskia Goes of Imperial College London, who was not involved in the work, reviewed the data and called the detection “plausible,” noting that narrow columns are notoriously hard to image.

Oman’s land lifts without any volcano

Even without lava, surface clues do exist. Eastern Oman’s Salma Plateau is puzzlingly high, topping 6,500 feet (1,980 meters), despite little crustal shortening.

GPS and shoreline studies show the coast is still inching upward at under 0.04 inches (0.1 centimeters) per year. Dynamic support from hot, buoyant mantle at depth offers the simplest explanation for this.

Similar uplift blankets the Yellowstone area, where the well‑known plume feeds long‑lived volcanic and hydrothermal activity in the American West. Oman’s quieter rise suggests plumes can lift crust even when they stay bottled deep below solid rock.

Hidden plume may have shifted India’s path

Geological reconstructions hint that the Dani plume slid under the Indian Plate about 40 million years ago, coinciding with a subtle eastward bend in India’s path. Pilia’s group argues that viscous drag from the plume’s flow nudged the plate like a hidden hand.

Torque calculations in the study show that a conduit around 125 miles (201 kilometers) wide, moving a few cubic miles of hot rock per year, could supply the needed force. No other nearby tectonic event explains the timing as neatly.

If a single, amagmatic plume can steer continents, multiple hidden plumes may have quietly shaped plate motions through Earth’s past.

Why hidden plumes matter

The Dani plume also carries implications for Earth’s heat budget. If many columns like it bypass slow mantle convection, more heat than expected streams straight from the core, potentially shortening estimates of how long the inner dynamo can continue to run.

Future arrays of ocean‑bottom seismometers and satellite gravity missions could uncover other silent plumes under thick cratons or old ocean basins, refining models that tie deep‑Earth processes to surface hazards and resource formation.

The new findings suggest the Dani plume may trace its roots to the same deep reservoir as the Afar plume, which is located beneath the Horn of Africa.

Seismic imaging from the DETOX‑P3 global tomography model reveals that both plumes could be branches of a broader low‑velocity structure at the core‑mantle boundary, which stretches thousands of miles across the lower mantle.

This tree‑like formation supports growing theories that mantle plumes may not rise as isolated columns but as parts of interconnected superplume networks.

If so, hotspots like Afar, Yellowstone, and now Oman might share common origins, linking surface activity across continents to single, deep‑Earth sources.

New tools reveal hidden mantle plumes

Traditional methods for detecting mantle plumes rely heavily on surface volcanism, which may overlook features hidden under thick continental crust.

The Dani plume shows that relying on lava flows and volcanic rocks alone can miss major drivers of Earth’s internal dynamics.

Instead, combining seismic tomography, plate motion analysis, and topographic signals opens new paths for identifying ghost plumes.

This interdisciplinary approach could help researchers locate more hidden structures in places that were once thought plume-free, thus reshaping how we map the heat flow from Earth’s core to its surface.

The study is published in Earth and Planetary Science Letters.

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