200 million years later, Africa is still falling apart, as is Madagascar, a new study says

The world as we know it today is the result of millions of years of tectonic changes and shifts. The way continents look now is very different from what they did decades ago and are constantly changing. Scientists have now found that the African continent is gradually breaking down into numerous tectonic blocks and the massive island of Madagascar is also disintegrating into smaller islands.

According to an international team of scientists, the separation is occurring throughout the East African Rift System and extending to the island of Madagascar, which is located off the coast of Southeast Africa. The authors claim that the rupture is a continuation of the dissolution of the supercontinent Pangea that began 200 million years ago. However, nothing major is expected to happen in our times.

“The modern day disintegration rate is millimeters per year, so it will take millions of years for new oceans to start forming. The rate of extension is faster in the north, so we will see the new oceans forming there first. , “D. Sarah Stamps, lead author of the study, said in a statement.

Changing continental faces

Pangea was a huge supercontinent that encompassed almost every continent. The unique landmass was surrounded by Panthalassa, a global ocean. The mega-continent is believed to have assembled in its entirety during the early Permian era: from 299 million to 273 million years ago. The breakup of Pangea is said to have started during the early Jurassic era, which was about 201 million to 174 million years ago. This gradual disintegration of Pangea led to the formation of the Atlantic and Indian oceans and, of course, the modern continents.

Like the face of the Earth, the aspect is changing, continents including Africa are bound to change. The study used new GPS datasets of highly accurate surface movements in Madagascar, East Africa and other islands that dot the Indian Ocean, along with additional geological data. The authors tested numerous configurations of the region’s tectonic blocks with the aid of computer models. Tahiry Rajaonarison, a PhD student in Geosciences, assisted Stamps in collecting the data.

Redrawing the boundaries

Through a series of extensive statistical tests, the team has drawn new boundaries for the Somali plate – a minor tectonic plate straddling the equator – and the Lwandle microplate – one of the three tectonic blocks that form the African plate. Designing this approach allowed the authors to verify whether the surface motion data were consistent with the motion of the rigid plates.

“Accurately defining plate boundaries and assessing whether continents diverge along zones that deform tightly or across large zones of diffuse deformation is crucial to unraveling the nature of continent disintegration. In this paper, we redefined it as the largest continental rift in the world. world is getting a new solution for GPS speed, ”Stamps said.

A gradual disintegration

The data revealed that the separation process was more distributed and complicated than previously believed. “Most previous studies have suggested that the extension is located in narrow areas around microplates that move independently of the surrounding larger tectonic plates,” Stamps noted.

In a specific region, the team found that the increase spanned a large region. The distributed extent was about 600 kilometers (372 miles) wide and encompassed East Africa and the whole of Madagascar. Specifically, the island is actively breaking down and its southern part is peeling off with the Lwandle Plate. The central part of Madagascar is said to move with the Somali plate. However, the rest of the island is flexibly disintegrating, Stamps pointed out.

Another interesting aspect of the study is the discovery of a large zone of deformation, a region that is undergoing simultaneous contraction and elongation. This can help scientists gain new insights into the recent and ongoing volcanic and seismic activity occurring in the Comoros Islands, a group of volcanic islands located in the Indian Ocean between Madagascar and East Africa.