Scientists Discover Hidden Mountains 100 Times Taller Than Everest Inside Earth

Massive Underground Structures Challenge Earth Science

Deep beneath our feet, buried 1,200 miles (2,000km) beneath the surface, lie two enormous continent-sized structures that reach heights of roughly 620 miles (1,000km) . These colossal formations dwarf every mountain on Earth's surface, including Mount Everest, by a factor of 100. To put it into perspective, Mt. Everest is 8.9 kilometers (5.5 miles) tall, which means the subterranean islands are 100 times taller than the peak .

The two blobs sit in the mantle on top of Earth's core, under the Pacific Ocean on one side and beneath Africa and the Atlantic Ocean on the other . Known scientifically as Large Low Seismic Velocity Provinces (LLSVPs), these mysterious formations have puzzled researchers since their discovery through seismic analysis in the late 20th century.

"Nobody knows what they are, and whether they are only a temporary phenomenon or if they have been sitting there for millions or perhaps even billions of years," explains Dr. Arwen Deuss, head researcher and seismologist at Utrecht University who led the groundbreaking study published in Nature.

Ancient Relics Challenge Mantle Theory

Recent research has revealed these structures possess properties that contradict long-held assumptions about Earth's interior. "Against our expectations, we found little damping in the LLSVPs, which made the tones sound very loud there. The findings revealed that the LLSVPs, despite being hot, do not significantly dampen seismic waves" , according to study co-author Sujania Talavera-Soza.

This discovery suggests the LLSVPs are composed of larger mineral grains compared to surrounding mantle material. "Those mineral grains do not grow overnight, which can only mean one thing: LLSVPs are lots and lots older than the surrounding slab graveyards" , Talavera-Soza explained. These hidden islands are said to be ancient, more than half a billion years old , though some estimates suggest they could date back to Earth's formation four billion years ago.

This insight suggests the LLSVPs are not part of the mantle's convection processes and have remained largely unchanged for vast periods. The rigidity and age of the LLSVPs challenge the notion of the mantle as a uniformly mixed system .

Impact on Earth's Surface Activity

These underground giants aren't just geological curiosities - they actively influence surface phenomena. Mantle plumes – columns of hot material rising from deep within the Earth – are believed to originate at the edges of LLSVPs. These plumes eventually cause volcanic activity, such as that seen in Hawaii .

Geochemists have long tried to explain why lava from Hawaii and other hot spot locations like Samoa, the Galápagos Islands and Iceland has unique chemical signatures. For example, lava from these hot spots contains a relatively high concentration of helium-3 — a primordial relic which predates the origin of the solar system .

Reshaping Our Understanding

The existence of these ancient, stable structures fundamentally alters our understanding of Earth's interior dynamics. It goes against standard geography books by suggesting the Earth's mantle 'cannot be well mixed' and doesn't flow like we previously thought . Instead of the constantly churning, well-mixed system scientists once envisioned, the mantle appears to contain remarkably stable regions that have persisted for billions of years.

These discoveries open new questions about planetary formation and evolution. If such massive structures can remain stable for eons while surrounded by dynamic mantle flow, they may preserve chemical signatures from Earth's earliest history. As researchers continue mapping these underground continents, they're essentially reading chapters from our planet's ancient story - one written in rock formations taller than anything we see on the surface, hidden in the depths where no human will ever venture.