Volcanoes to split Africa: scientists – ABC Science
Volcanic activity may split the African continent in two and create a new ocean, say scientists.
Two volcanic eruptions in September 2005, which produced a 60-kilometre split in north-eastern Ethiopia, have enabled scientists to further examine the earth’s tectonic movements.
The research is published in Geophysical Research Letters.
Researchers say faults and fissures, which normally occur deep down on the ocean floor, are the main processes by which continents gradually break off from each other.
But this report suggests that highly active volcanic boundaries along the edges of tectonic plates can suddenly break apart in large sections.
“The significance of the finding is that a huge magnetic deformation can happen within a few days,” says lead investigator Atalay Arefe of Addis Ababa University in Ethiopia.
Arefe and colleagues cite Africa, which underwent such a similar phase when it split from America millions of years ago, as an example.
“Normally, such phenomena happen beneath the ocean, which is inaccessible, [and amkes experiments difficult and expensive to cary out]. But in Afar [Ethiopia], it’s quite a natural laboratory for us to carry those [experiments] out,” says Arefe.
He says the 60-kilometre split gives scientists clues as to what might happen to the region in the future.
“The ocean’s formation is happening slowly, likely to take a few million years. It will stretch from the Afar depression (straddling Ethiopia, Eritrea and Djibouti) down to Mozambique,” he says.
Professor Emeritus Ken MacDonald of the University of California says the work is a breakthrough in our understanding of how continental rifting leads to the creation of new oceans.
“For the first time [it's been] demonstrated that activity on one rift segment can trigger a major episode of magma injection and associated deformation on a neighbouring segment,” he says.
Not good news
But Professor Cindy Ebinger of the University of Rochester, who was also involved in the study, says such large scale events aren’t great news for populations living close by.
The Afar region, known for its salt mines and active volcanoes, is one of the lowest and hottest places on the planet.
Since the two eruptions in 2005, Ebinger has measured 12 similar, though less intense, seismic events in the region.
Ebinger and colleagues will continue to monitor the rift to understand how it evolves.