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Triumph of the Weird
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Join Date: Sep 2015
Location: Houston, TX USA
Posts: 6,973
Favourites (more):
BB19: Anamelia CBB22: Gabby Allen
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Triumph of the Weird
Join Date: Sep 2015
Location: Houston, TX USA
Posts: 6,973
Favourites (more):
BB19: Anamelia CBB22: Gabby Allen
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An Enormous Crack Just Opened Up In Africa, Evidence Africa Is Splitting In Two
An Enormous Crack Just Opened Up In Africa, Evidence Africa Is Literally Splitting In Two
https://www.forbes.com/sites/trevorn.../#4417feec3941
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An Enormous Crack Just Opened Up In Africa, Evidence Africa Is Literally Splitting In Two
A massive crack suddenly appeared in Kenya, prompting new discussion on the breakup of Africa into two land masses. The crack continues to grow in size as heavy rainfall in Kenya's Narok County exacerbates the kilometer-sized chasm.
The sudden appearance of the crack is related to a regional zone of weakness and broadly associated with the continued breakup of the African continent. The leading hypothesis behind the breakup of the African continent is caused by an underlying superheated plume. This plume is causing Africa to split in two along the eastern edge of the continent. Thankfully, the rifting process will take many millions of years as the crust begins to thin and sink and a small seaway begins to intrude the rift zone.
Splitting a continent in two is quite common, for instance, it led to the opening of the Atlantic Ocean. Notice how Africa and South America would fit perfectly together, this is because they were once one landmass, eventually sutured apart by the Mid-Atlantic Ridge. While scientists have known for quite some time about the rifting in Africa, the underlying cause has been hard to pin down. Evidence suggests it is due to a superplume upwelling along the eastern edge of Africa, figuratively "burning" a hole in Earth's crust.
This superplume created the East African Rift System (EARS), the system associated with the breakup of the African continent. The East African Rift Valley, produced as a result of the ongoing splitting of the African continent, stretches more than 3,000 km from the Gulf of Aden to Zimbabwe. The rifting, which began about 25 million years ago, will eventually create two separate continental masses associated with the Somalian and Nubian tectonic plates. The process, however, will take millions of years at the current spreading rate of a few millimeters per year.
While the larger rifting system could be the underlying mechanism for the 50 feet deep and 66 feet wide chasm, the sudden appearance was likely due to heavy rainfall in the area, exposing the crack. The surface expression of the rifting is responsible for a wide zone of volcanism, seismic activity, uplift and subsidence of the ground, and the creation of fissures and cracks.
Over millions of years, the eastern edge of Africa will begin to be separated from the rest of Africa by a small and shallow sea. As rifting continues, Earth will exhibit a large island in the Indian Ocean. This island will likely consist of parts of Ethiopia, Somalia, Kenya, and Tanzania.
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Giant Crack in Africa Will Create a New Ocean
https://www.livescience.com/10592-gi...ate-ocean.html
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Giant Crack in Africa Will Create a New Ocean (2009)
A 35-mile rift in the desert of Ethiopia will likely become a new ocean eventually, researchers now confirm.
The crack, 20 feet wide in spots, opened in 2005 and some geologists believed then that it would spawn a new ocean. But that view was controversial, and the rift had not been well studied.
A new study involving an international team of scientists and reported in the journal Geophysical Research Letters finds the processes creating the rift are nearly identical to what goes on at the bottom of oceans, further indication a sea is in the region's future.
The same rift activity is slowly parting the Red Sea, too.
Using newly gathered seismic data from 2005, researchers reconstructed the event to show the rift tore open along its entire 35-mile length in just days. Dabbahu, a volcano at the northern end of the rift, erupted first, then magma pushed up through the middle of the rift area and began "unzipping" the rift in both directions, the researchers explained in a statement today.
"We know that seafloor ridges are created by a similar intrusion of magma into a rift, but we never knew that a huge length of the ridge could break open at once like this," said Cindy Ebinger, professor of earth and environmental sciences at the University of Rochester and co-author of the study.
The result shows that highly active volcanic boundaries along the edges of tectonic ocean plates may suddenly break apart in large sections, instead of in bits, as the leading theory held. And such sudden large-scale events on land pose a much more serious hazard to populations living near the rift than would several smaller events, Ebinger said.
"The whole point of this study is to learn whether what is happening in Ethiopia is like what is happening at the bottom of the ocean where it's almost impossible for us to go," says Ebinger. "We knew that if we could establish that, then Ethiopia would essentially be a unique and superb ocean-ridge laboratory for us. Because of the unprecedented cross-border collaboration behind this research, we now know that the answer is yes, it is analogous."
The African and Arabian plates meet in the remote Afar desert of Northern Ethiopia and have been spreading apart in a rifting process — at a speed of less than 1 inch per year — for the past 30 million years. This rifting formed the 186-mile Afar depression and the Red Sea. The thinking is that the Red Sea will eventually pour into the new sea in a million years or so. The new ocean would connect to the Red Sea and the Gulf of Aden, an arm of the Arabian Sea between Yemen on the Arabian Peninsula and Somalia in eastern Africa.
Atalay Ayele, professor at the Addis Ababa University in Ethiopia, led the investigation, gathering seismic data with help from neighboring Eritrea and Ghebrebrhan Ogubazghi, professor at the Eritrea Institute of Technology, and from Yemen with the help of Jamal Sholan of the National Yemen Seismological Observatory Center.
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Last edited by Maru; 05-04-2018 at 12:58 AM.
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