Sahara Reveals Remains of Ancient River

砂下古河

Using a satellite-born sensor system that can penetrate through several feet of dry surface sediments, researchers found the dry remains of an ancient river system winding for hundreds of miles below the Saharan 

使用基于卫星的可以穿透数尺干燥沉积物的传感系统，研究人员发现了潜藏于撒哈拉沙漠下方、延绵几百里的古代水系遗迹。

撰文/播音 茱莉亚·罗森（Julia Rosen）

翻译 M

审核：邰伦玥

"The city of Tanis was consumed by the desert in a sandstorm which lasted a whole year. Wiped clean by the wrath of God." Indiana Jones's friend Marcus Brody, explaining the fictional fate of the city of Tanis in Raiders of the Lost Ark.

“塔尼斯古城在一场持续一整年的沙尘暴中被吞噬，消失于上苍的愤怒中。”印第安纳·琼斯的朋友，马库斯·布罗迪，在电影夺宝奇兵中解释坦尼斯的虚构命运。

Back in real life, scientists have found something else covered by the Sahara's sea of sand: an ancient river system. The remains of the main channel—which dried up long ago—wind beneath the west African desert for more than 300 miles before reaching the Atlantic Ocean.

回到现实中，科学家们已经发现了其他藏于撒哈拉沙漠黄沙之中的东西：一个古代水系。其早已干涸的干流，在西非沙漠之下延绵了超过300英里，最终流入大西洋。

Researchers led by Charlotte Skoniezcny of the University of Lille in France uncovered the system using a kind of satellite-borne radar that can penetrate through several feet of dry surface sediments like sand. The scientists think that the network may extend even farther inland, but thick dunes prevented them from mapping it. They report their findings in the journal Nature Communications. [Charlotte Skoniezcny et al, African humid periods triggered the reactivation of a large river system in Western Sahara]

来自法国里尔大学的由夏洛特?斯科尼兹尼所领导的研究人员们使用了卫星携带的雷达系统发现了这个水系。这种卫星雷达能够穿透数尺的干燥沉积物，例如沙。研究人员认为该水系可能在大陆中延展更大的范围，然而厚重的沙丘阻止了进一步的测绘。他们将结果发表在了《自然通讯》上。

The discovery solves the mystery of what created a vast underwater canyon off the coast of Mauritania in northwest Africa. The subsurface ravine looks like those that form at the mouths of massive rivers today. But researchers had only hypothesized the existence of major waterways in West Africa until now.

这项发现解开了非洲西北毛里塔尼亚外围的广阔的海底峡谷形成之谜。这个水底沟壑就像那些现今的大型河流的入海口一样。然而在过去，研究人员只能猜测这些主要水道存在于西非。不过现在不同了。

The fact that rivers raged at the surface in this region sheds light on the Sahara's tumultuous history. Scientists know that this vast desert wasn't always dry. At certain times in the past, it boasted green grasslands teeming with life. The researchers think the Sahara's lost river last flowed 6,500 years ago, revealing just how fast west Africa's climate can change. Maybe not quite as fast as Indiana Jones swapping out a bag of sand for a golden idol. But still, surprisingly fast. "Wiped clean."

过去奔流在这个区域的地表的河流揭示了撒哈拉沙漠激荡的历史。研究人员知道了这片广阔的沙漠并不是总是干燥荒芜的。在过去，这个地方曾被翠绿的草地覆盖，充满生机。研究人员认为，撒哈拉沙漠的河流在6500年前消失，这显示了非洲气候变化之快。也许没印第安纳?琼斯以一包沙调包了一个金雕像那么迅速。不过，这速度仍然惊人，并丝毫不留痕迹。