评论
打印
Scientists say a huge crater formed by a meteorite strike in present-day Greenland is much older than first thought.
科学家表示，在如今的格陵兰岛，陨石撞击形成的一个巨大陨石坑的年代比人们最初认为的要古老得多。
The 31-kilometer-wide crater was first discovered in 2015 under thick ice at Greenland's Hiawatha Glacier.
这个31千米宽的陨石坑于2015年在格陵兰岛的海厄瓦萨冰川厚厚的冰层下首次被发现。
The ice covering the crater, called an ice sheet, is about one kilometer deep.
覆盖在陨石坑上的冰被称为冰盖，大约有一千米深。
The crater remained hidden until it was identified by radar equipment and scientists decided to investigate.
这个陨石坑一直隐藏在冰川下，直到它被雷达设备发现，科学家们决定对其进行调查。
At first, researchers estimated the massive hole might have formed about 2.6 million years ago, or even as recently as 13,000 years ago.
起初，研究人员估计这个巨大的洞可能形成于大约260万年前，甚至是最近的1.3万年前。
But they announced March 9 that new dating methods suggested the crater is about 58 million years old.
但他们在3月9日宣布，新的测年方法表明，这个陨石坑大约有5800万年的历史。
The researchers said they based their findings on dating methods that measured the breakdown of radioactive material.
研究人员说，他们的调查结果基于测量放射性物质分解的测年方法。
Their results were recently released in a study in the publication Science Advances.
他们的调查结果最近发表在《科学进展》杂志上。
The new information suggests the strike happened about 8 million years after an asteroid hit an area in Mexico's Yucatán Peninsula.
新的信息表明，该陨石撞击发生在一颗小行星撞击墨西哥尤卡坦半岛地区约800万年后。
That climate-changing event is blamed for causing the disappearance of more than 70 percent of Earth's plant and animal life.
该气候变化事件是导致地球上70%以上的动植物消失的罪魁祸首。
All dinosaurs that were not bird-like disappeared.
所有不像鸟的恐龙都消失了。
At the time the meteorite hit Greenland, it was not the icy place it is today.
当陨石撞击格陵兰岛时，它还不是如今这个结满冰的地方。
It is believed to have been covered with rain forests populated with plant and animal life that followed the disappearance of most of the dinosaurs.
人们认为，在大多数恐龙消失后，这里曾被热带雨林覆盖，动植物在这里生长。
Researchers say the meteorite released millions of times more energy than an atomic bomb, leaving a crater big enough to swallow the city of Washington D.C.
研究人员表示，该陨石释放的能量是原子弹所释放的能量的数百万倍，留下的陨石坑大到足以吞没华盛顿特区。
Gavin Kenny is with Sweden's Museum of Natural History and was the lead writer of the study.
瑞典自然历史博物馆的加文·肯尼是这项研究的主要作者。
He told Reuters that forceful air from the event "would have knocked down most trees within tens to hundreds of kilometers."
他告诉路透社，陨石撞击产生的强烈气流“可能吹倒了数十至数百公里内的大多数树木”。
In addition, an explosion from the strike would have set trees on fire and caused widespread forest fires.
此外，陨石撞击引发的爆炸使树木着火，并引发了大范围的森林火灾。
Michael Storey, with Denmark's Natural History Museum, was a co-writer of the study.
丹麦自然历史博物馆的迈克尔·斯托里是这项研究的合著者。
He said the new information does not provide clear evidence that the impact had long-lasting effects on world climate.
他说，新的信息没有提供明确的证据表明这种影响对世界气候有持久的影响。
But, Storey added, he thinks such effects were "unlikely."
但是，斯托里还说，他认为这种影响是“不太可能的”。
Kenny noted that these kinds of strikes only happen every few million years.
肯尼指出，这种陨石撞击每隔几百万年才会发生一次。
So, he said, "We don't need to be very worried about such an impact happening anytime soon."
因此，他说，“我们不必非常担心这样的影响会很快发生。”
I'm Bryan Lynn.
布莱恩·林恩为您播报。
译文为可可英语翻译，未经授权请勿转载！
