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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. 
Full article at:

http://news.yahoo.com/s/livescience/giantcrackinafricawillcreateanewocean

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ORIGINAL: DesFIP

Nothing to worry about immediately. Apparently this rifts widen one inch a year after the initial crack. Be quite a while till they connect to an existing body of water large enough to fill it.

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Its interesting to me that the earth is still very geologically active and that changes can be so sudden and drastic like this.

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Its interesting to me that the earth is still very geologically active and that changes can be so sudden and drastic like this.

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ORIGINAL: LadyEllen

Good grief.

E

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Recent Midwest Quakes Called Aftershocks from 1800s

The small earthquakes that sporadically rattle the central United States may actually be aftershocks from a few extremely large quakes that occurred in the region almost 200 years ago, according to a new study

The New Madrid Earthquakes, which struck between December 1811 and February 1812, are some of the strongest seismic events ever to occur in the contiguous United States in recorded history. The largest quake is estimated to have been 8.0 in magnitude and was powerful enough to temporarily make the Mississippi River flow backwards. The heart of the seismic activity was near the town of New Madrid, Missouri, close to the Kentucky and Tennessee borders.

The town has shaken with numerous earthquakes since, from tiny ones that don't cause much of a stir, to moderate sized ones, such as a 5.2 quake in 2008. Some scientists suspected that many of these events were really repercussions from the big 1811 and 1812 earthquakes. For one thing, "there's no motion across the fault now, so nothing's going on, but yet there are still small earthquakes there," said Seth Stein, the study's lead author and a professor of geological sciences at Northwestern University. The small quakes also occur on the same fault plane that researchers believe is responsible for the big quakes. Furthermore, the present-day temblors are getting smaller with time, which is a characteristic of aftershocks, Stein said. And when larger quakes do occur, they happen at the corners of the fault section that scientists think broke during the 19th century earthquakes, a pattern that suggests these are aftershocks, Stein told LiveScience.

(Full article here)

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Source of Major Quakes Discovered Beneath U.S. Heartland

...One team of seismologists had thought that high density pillow lavas in the lower crust beneath the New Madrid region could have pulled the crust downward and thereby generated surface stresses that triggered the quakes.

Now, Allessandro Forte of the Université du Québec à Montréal and his colleagues have arrived at a more dramatic mechanism—an ancient, giant slab of Earth called the Farallon slab that started its descent under the West Coast 70 million years ago and now is causing mayhem and deep mantle flow 360 miles beneath the Mississippi Valley where it effectively pulls the crust down an entire kilometer (.62 miles).

"This remarkable localization of flow in the mantle below New Madrid, originating so deep below the surface, was completely unrecognized prior to our work," Forte told LiveScience.

Slabs like this that sink oceanic crust are called subduction zones, and those adjacent to Japan produce intense and damaging seismic activity. "We have discovered an analogous subduction zone, deep inside the Earth below the central Mississippi River Valley," Forte said.
Full article here:

http://www.livescience.com/environment/070502_newmadrid_quake.html

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ORIGINAL: Musicmystery

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Its interesting to me that the earth is still very geologically active and that changes can be so sudden and drastic like this.

To me too, Sanity.

Thanks for posting this.

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ORIGINAL: Sanity


We live our lives in the shadow of geological time but once in a while...



Well, you just never know.

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ORIGINAL: DemonKia

lol

Trust me, I pay attention to news about volcanoes . . . . .

However, I also note the igneous boulders that stud the entirety of the northern half of California, a distance of hundreds of miles . .. . . They are the result of the super-volcano that exploded & of which Shasta & Lassen (our 2 local volcanic events) are mere remnants from the edge of that enormous geo-event. Happened millenia ago, & being in Nevada & Oregon, possibly Utah & Idaho, wouldn't have helped keep one away . . . .

Mama Earth, so much bigger than us . ... .

& trickier. Anyone wanna hazard a guess where the largest earthquake happened (& when) in the lower-48 states of the USofA?