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On September 14, 2005, there was an earthquake in a remote part of Afar, a region in northern Ethiopia.
2005年9月14日，在埃塞俄比亚北部的一个偏远地区发生了一场地震。
It wasn't very strong, but it was the first of many.
地震震感不强，但却是首次出现这种情况。
Over the next 12 days, there were over a hundred more quakes, most of them also relatively small.
在接下来的12天里，出现了一百多次振动，大部分也相对较小。
Then, on September 26, a nearby volcano called Dabbahu erupted.
然后在9月26日，附近的一个火山Dabbahu爆发了。
This was its first eruption in recorded history, and it came from a flat part of the volcano a few kilometers from the summit.
这是历史记录中该火山首次爆发，其来自于距离山顶几千米处的火山平坦地带。
The eruption didn't do too much harm—no people were seriously hurt, and at most it killed a couple hundred goats and camels.
此次火山爆发并未造成过多伤害—没有人员严重受伤，最多是导致两百只山羊和骆驼死亡。
But it opened up a gigantic crack in the earth, which grew to 60 kilometers long and as much as eight meters wide—in only ten days.
但是这次火山爆发打开了地球上的一条巨大的裂缝，仅在10天内就长到60千米长，8米宽。
And as you can probably imagine, this caught the attention of geologists around the world.
大家可以想象，这吸引了全球地质学家的注意。
It turns out that as dramatic as it was, the crack was just one of the latest symptoms of an ongoing seismic shake-up in Africa
事实证明此次引人注目的大裂口不过是非洲正在形成的地震剧变最新症状之一，
that's eventually going rip the continent in two, leading to the creation of a brand-new ocean.
非洲地震剧变最终会将大陆一分为二，创造出一个新海洋。
Right now, eastern Africa is going through a process called rifting,
现在，非洲东部正经历的这一过程叫做裂谷作用，
where the tectonic plates that make up the Earth's crust and upper mantle pull apart from each other.
组成地球地壳和上地幔的构造板块彼此分开。
A giant plume of magma rising from deep inside the mantle is forcing the African and Arabian plates away from one another,
从地幔深处升起的岩浆的巨大岩浆柱迫使非洲和阿拉伯板块分开
forming a rupture in the Earth's surface.
形成地区表面的一个断裂。
The result is the Great Rift Valley, which stretches more than 3000 kilometers through the eastern part of the continent.
结果便形成了东非大裂谷，穿过大陆东部，延伸3000千米。
Scientists have been studying the Great Rift Valley since around the turn of the 20th century,
自20世纪东非大裂谷出现以来，科学家们便一直在研究它，
when an English geologist named John Gregory encountered it for the first time.
当时一名英国地质学家约翰·格雷戈里首次发现了东非大裂谷。
Even though the theory of plate tectonics wouldn't be fully accepted for another 50 years or so, he realized how important it might be.
即便再过50多年，板块构造说仍没有被完全接受，他还是察觉到了它的重要性。
The valley is a system of several fractures that began forming at different times, and it's home to lots of seismic activity.
这个大裂谷是几种断裂构造的一种体系，在不同时期开始形成，其中发生过很多地震活动。
The pressure from tons of magma bubbling up is what leads to earthquakes and volcanic eruptions like what happened in 2005.
来自许多岩浆迸发的压力造成地震和火山喷发，比如2005年的火山喷发。
For a study published in 2018, scientists installed two seismic networks in Ethiopia and Eritrea.
在2018年发表的一项研究中，科学家在埃塞俄比亚厄立特里亚安装了两个地震网络。
And these networks of seismographs recorded almost 5,000 earthquakes of at least magnitude 2.0 in two years.
两年内，地震仪的这些网络记录了将近5千次震级至少为2.0的地震。
All that activity has spawned other volcanoes, too—one, called Nyamuragira, erupted fifteen times between 1894 and 1979.
所有那些活动也引起了其他火山爆发，一个是尼亚穆拉吉拉火山，在1894年到1979年间爆发15次。
What's happening in eastern Africa is actually more common at the bottom of the ocean,
实际上在东非所发生的活动在海洋底部非常普遍，
where magma bubbling up into tectonic rifts forms features called seafloor ridges and helps drive the movement of continental plates.
在海洋中岩浆沸腾至构造裂谷形成海底脊特征并帮助驱动大陆板块的运动。
But the activity in Africa is giving geologists a chance to study the process up close—no submarines needed.
但是非洲发生的这次运动给了地质学家近距离研究该过程的机会—无需用上潜水艇。
As it turns out, what happened in 2005 was that a huge length of the rift cracked open all at once,
事实证明2005年所发生的是裂缝巨大的长度是立即就断开的，
beginning with the volcanic eruption and spreading in both directions from there.
和火山喷发一同开始，从这里向两个方向扩散。
This was a bit of a surprise to scientists, who previously thought that such cracks—on the ocean floor as well as on land—only broke open a little bit at a time.
科学家们有些惊讶，他们过去认为这样的裂缝—在海洋底部和陆地上—一次只断开一点点。
Eventually, the Horn of Africa is going to split off from the rest of the continental plate and go its own way.
最终，非洲之角将从大陆板块剩余部分断裂开，自立一路。
Large areas of the Great Rift valley are below sea level, cut off from the ocean only by a small piece of higher land in Eritrea.
东非大裂谷的大部分区域都在海平面以下，被厄立特里亚稍高于陆地的一小块与海洋隔离开来。
So when the split finally happens, seawater is going to come flooding into the rift, turning the Horn of Africa into an island and creating a new ocean.
所以当断裂形成时，海水开始涌入裂缝，将非洲之角变成一个岛，并创造出了一个新的海洋。
Odds are none of us will actually get to see the new ocean.
不过我们都不可能真正的看到这个新海洋。
The process has been happening slowly for about 30 million years, and the rift is only widening at an average rate of a couple of centimeters a year.
这个过程发生的非常慢，约要3千万年，而断裂扩张的平均速度是每年一两厘米。
So, it will probably be tens of millions of years before traveling from Sudan to Somalia requires a boat.
所以，在从苏丹到索马里需要乘船前，要等数千年。
But in the meantime, we get to watch our planet reshape itself, giving us a teaser for what the world will look like long after we're gone.
但是在此期间，我们可以看到我们的星球重塑自己，让我们猜想我们消失后，这个世界将会变成什么样。
Thanks for watching this episode of SciShow, and a special thanks to our President of Space, Matthew Brant! Thanks, Matthew, for your support!
感谢收看本期《科学秀》，特别感谢Space总裁Matthew Brant！谢谢你的支持！
And if you want to help support us or just get some cool rewards like access to our monthly livestream, head on over to patreon.com/scishow.
如果你想帮助支持我们或是想获得一些超酷的奖品，请登录patreon.com/scishow。
