Giant waves deep in the Earth’s interior «lift» continents, — new study

According to a new study, the impressive cliffs and high plateaus are caused by the same wave that rises in the Earth’s middle layer when continents are pushed apart.

Geologists at the University of Southampton (UK) have discovered that high plateaus in the interior of continents are formed by processes that occur deep inside the Earth, hundreds of kilometers away from where they were formed.

Thomas Gernon, the lead author of the study, explains that the divergence of the continents triggers a wave in the Earth’s mantleThe middle layer of the Earth (mantle) is the layer between the Earth's crust and core, consisting of viscous silicate rocks. The mantle plays a key role in the processes of plate tectonics.. This wave moves slowly inland over tens of millions of years, causing plateau uplift.

The scientists studied three known coastal escarpmentsEscarpments are steep slopes or cliffs that often form along coasts or at plateau boundaries and can extend for long distances., which were formed during the breakup of the last supercontinent GondwanaThe supercontinent Gondwana was an ancient continent that existed in the Paleozoic and Mesozoic eras and included the territories of modern South America, Africa, Antarctica, Australia, India, and Arabia.. They used topographic maps and computer modeling to show the connection between continental faults and the formation of escarpments.

The researchers studied escarpments along the coast of India (Western Ghats), in Brazil (High Plateau), and the Great Escarpment of South Africa. These escarpments extend for thousands of kilometers, and the interior plateaus can rise by a kilometer or more.

The analysis of mineral data showed that uplift and erosion on the plateau occurred simultaneously with the movement of the mantle wave deep below the surface. This process was extremely slow — the wave moved only 15–20 kilometers per million years.

Gernon suggests that this theory could explain the formation of other regions with escarpments and plateaus, such as in North and South Carolina or south of Cameroon. However, older formations may be less visible due to prolonged erosion.

Researchers have previously found that the same process of supercontinent breakup and mantle waves also affects the eruption of diamonds from the center of the Earth.

Research published in the journal Nature.

Source: Livescience