Recent research revealed that massive waves within Earth's mantle, set off by the splitting of continents, may play a key role in shaping significant landforms like high plateaus and steep escarpments.
When continents begin to break apart, towering cliff walls often emerge near the separating crustal boundaries. This rifting process triggers waves in the mantle that gradually move inward over millions of years, leading to the uplift of plateaus.
A study published in the journal Nature offers new insights into this geological phenomenon, suggesting that these dramatic land features are connected through deep mantle waves. Thomas Gernon, a geoscientist at the University of Southampton and the study's lead author, noted that these formations were previously believed to result from various distinct processes.
However, the research indicates they share a unified origin.
Gernon and his team examined three prominent escarpments that formed during the breakup of Gondwana, Earth's last supercontinent.
These include the escarpment along India's Western Ghats, one surrounding Brazil's Highland plateau, and the Great Escarpment in South Africa.
Their findings show that these escarpments are aligned with continental rift zones, suggesting that they were shaped by the same underlying process. Computer models supported this, demonstrating that disturbances in the mantle caused by rifting generate deep waves that travel inward, contributing to the rise of plateaus.
Additionally, the study analyzed mineral data, showing that the uplift and erosion of these plateaus were synchronized with the movement of mantle waves. These waves, which move slowly - around 9 to 12 miles per million years - gradually erode the strong roots anchoring the continents. This process makes the continents more buoyant, causing them to rise.
The researchers propose that similar mantle wave activity could explain other escarpment and plateau formations around the world. However, older landforms may have been extensively altered by erosion, making them more challenging to study.