Gallery I
Shifting Plates
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Those Unexpected Cracks In The Earth

By James Donahue

The eruption of the volcano Dabbahu in Ethiopia in 2005 resulted in a deep rip in the earth that has drawn the attention of world scientists. It is a 35-mile-long tear measuring up to 20 feet in width. Now an international team of scientists believes that strange crack was caused by a movement of tectonic plates that are even parting the Red Sea and someday may split Africa into two continents.

If they are right, this appears to mean that the edge of a new tectonic plate has been revealed that does not appear on world maps.

Of course the whole concept of plate movement is somewhat theoretical, since humans have never been able to dig deep enough or get a good cross-section view of what is going on deep under our feet.

The theory, which is substantiated by such supportive theories as continental drift and earth crust movement from earthquakes, is that the planet’s rock-hard outer crust is broken into massive thick plates floating on hot magma that drift around, sometimes crashing into each other.

The belief is that the plates, which can range from 50 to 250 miles in thickness, can move both horizontally and vertically. The movement is extremely slow in terms of time as we know it, so it takes hundreds of thousands of years for the plate movements to cause major changes in world geography.

Support for the theory of plate movement and continental drift can be easily found when studying maps showing the newly charted floor of the Atlantic Ocean, which is found to have a deep trench that follows the shapes of both land masses to the east and west coasts. When maps of Europe and Africa are pushed up against maps of North and South America, all of the land masses appear to fit together somewhat like a jig-saw puzzle.

Thus the theory is that the land is resting on giant plates that have been slowly drifting apart. Some believe the movement is at a speed of no more than one to 10 centimeters a year. And this plate movement may account for the Earth’s seismic activity. The eruption of volcanoes and earthquakes seem to occur at plate   boundaries as they interact with one another.

Before the crack appeared in the Ethiopian desert, it was believed that the entire continent of Africa was riding on one large plate of its own. Some scientists have theorized that lesser cracks exist in these massive plates. But the eruption of Mt. Dabbahu and the appearance of that large rift in the land nearby is suggesting something more important is happening.

Either the African plate is splitting apart, or there always was a split in the plate leading through the land where the new crack has appeared. Scientists now say that if this plate drift continues in the way it appears to be moving, Africa may someday split into two continents and they will be divided by a new ocean.

Will it happen in our lifetime? With plate movement measuring no more than a centimeter a year, this event is going to take a very long time. What we know is that if the Sun hasn’t yet turned into a red giant and ravaged the planets surrounding it, planet Earth will look quite different in the next few hundred million years.