The Angolan coastline reveals unexpected geological secrets. Researchers from Southern Methodist University (SMU) have uncovered rocks and fossils that tell the story of the formation of the South Atlantic Ocean, resulting from the separation of South America and Africa about 140 million years ago.
A research team from SMU discovered ancient rocks and fossils in Angola, tracing the separation of South America and Africa and the formation of the South Atlantic Ocean.
These discoveries, including fossils of now-extinct marine reptiles, provide clear evidence of a crucial event in Earth's history. The southern coastline of Angola, where the samples were extracted, presents the most complete geological record of the continental separation and the opening of the South Atlantic. The rocks and fossils found date from 130 to 71 million years ago.
Professor Emeritus Louis L. Jacobs of SMU, principal author of the study published in
The Geological Society, London, Special Publications, emphasizes that this discovery offers an unprecedented insight into the opening of the South Atlantic. Previously, no terrestrial region displayed the stages of this separation so clearly, as they were often concealed under the ocean or eroded.
The separation of Africa and South America, initiated around 140 million years ago, created fissures in the Earth's crust, releasing magma and forming a new oceanic crust. The evidence of these events had previously been gathered through geophysics and marine core samples, but never in one terrestrial region, making these Angolan discoveries particularly significant.
Angola allows for a detailed visualization of each phase of this geological chapter, from the initial separation to the creation of the South Atlantic Ocean. The work was conducted by an international team of paleontologists, geologists, and other specialists, analyzing rock formations and fossils discovered at eight distinct locations along the Angolan coast.
Since 2005, researchers have identified particular sediments indicating the evolution of the West African coast over millions of years. Lava deposits and faults show the separations of the continents, while marine sediments and marine reptile fossils reveal the culmination of the South Atlantic formation process.
For the first time, it is possible to document the absence of an ocean, the emergence of a new ocean, and the abundance of marine life, thus providing a complete narrative of the South Atlantic's formation.