双语新闻：科学家:地核正在泄漏

Scientists have detected a surprising amount of a rare version of helium, called helium-3, in volcanic rocks on Canada’s Baffin Island, lending support to the theory that the noble gas is leaking from Earth’s core — and has been for millennia.

科学家们在加拿大巴芬岛的火山岩中发现了数量惊人的稀有氦，称为氦-3，这为这种稀有气体从地核泄漏的理论提供了支持，这种理论已经存在了几千年。

The research team also detected helium-4 within the rocks.

研究小组还在岩石中发现了氦-4。

While helium-4 is common on Earth, helium-3 is more readily found elsewhere in the cosmos, which is why scientists were surprised to detect a larger amount of the element than had been previously reported from the rocks on Baffin Island. A study describing the discovery published recently in the journal Nature.

虽然氦-4在地球上很常见，但氦-3在宇宙的其他地方更容易找到，这就是为什么科学家们惊讶地发现，在巴芬岛的岩石中发现了比以前报道的更多的元素。最近发表在《自然》杂志上的一项研究描述了这一发现。

“At the most basic level, there is little 3He (helium-3) in the universe compared to 4He (helium-4),” said lead study author Forrest Horton, associate scientist in the department of geology and geophysics at Woods Hole Oceanographic Institution, in an email.

“在最基本的层面上，与4He(氦-4)相比，宇宙中只有很少的3He(氦-3)，”该研究的主要作者、伍兹霍尔海洋研究所地质和地球物理系的副科学家Forrest Horton在一封电子邮件中说。

“3He is rare in Earth because it has not been produced in or added to the planet in significant quantities and it is lost to space,” Horton added. “As Earth’s rocky portion stirs and convects like hot water on a stove top, material ascends, cools, and sinks.During the cooling stage, helium is lost to the atmosphere and then to space.”

霍顿补充说:“氦在地球上很稀有，因为它没有在地球上大量生产或添加，而是流失到太空中。”“当地球的岩石部分搅拌和对流时，就像炉子上的热水一样，物质上升、冷却和下沉。在冷却阶段，氦会流失到大气中，然后进入太空。”

Detecting elements that leak from Earth’s core can help scientists unlock insights into how our planet formed and evolved over time, and the new findings provide evidence to bolster an existing hypothesis about how our planet came to be.

探测从地核泄漏的元素可以帮助科学家了解我们的星球是如何随着时间的推移而形成和演化的，新的发现为支持关于我们的星球是如何形成的现有假设提供了证据。

A trove of ‘scientific treasures’

“科学宝藏”的宝库

Baffin Island, located in the territory of Nunavut, is the largest island in Canada. It’s also the fifth-largest island in the world.

巴芬岛位于努纳武特地区，是加拿大最大的岛屿。它也是世界上第五大岛屿。

A high ratio of helium-3 to helium-4 was first detected in Baffin Island volcanic rocks by Solveigh Lass-Evans as part of her doctoral studies under the supervision of University of Edinburgh scientist Finlay Stuart. Their findings were published in Nature in 2003.

在爱丁堡大学科学家芬利·斯图尔特的指导下，索尔维·拉斯-埃文斯在巴芬岛的火山岩中首次发现了氦-3和氦-4的高比例，这是她博士研究的一部分。他们的研究结果发表在2003年的《自然》杂志上。

The composition of a planet is a reflection of the elements that formed it, and previous research found that trace amounts of helium-3 leaking from Earth’s core supports the popular theory that our planet originated in a solar nebula — a cloud of gas and dust that likely collapsed due to the shock wave of a nearby supernova — which contained the element.

行星的组成是形成它的元素的反映，以前的研究发现，从地球核心泄漏的微量氦-3支持了一个流行的理论，即我们的星球起源于一个太阳星云——一个气体和尘埃云，可能是由于附近超新星的冲击波而坍塌的——其中含有这种元素。

Horton and his colleagues took it a step further when they conducted research on Baffin Island in 2018, studying the lava that erupted millions of years ago when Greenland and North America split apart, making way for a new seafloor. They wanted to investigate the rocks that may contain insights about the contents locked within Earth’s core and mantle, the mostly solid layer of Earth’s interior located beneath its surface.

霍顿和他的同事们在2018年对巴芬岛进行研究时更进一步，研究了数百万年前格陵兰岛和北美分裂时喷发的熔岩，为新的海底让路。他们想要研究那些可能包含地球核心和地幔(位于地表以下的地球内部的固体层)内容的岩石。

The researchers traveled by helicopter to reach the remote, otherworldly landscape of the island, where lava flows have formed towering cliffs, giant icebergs float by and polar bears stalk the coastline. Local organizations, including the Qikiqtani Inuit Association and Nunavut Research Institute, provided the researchers with access, advice and protection from the bears, Horton said.

研究人员乘坐直升机到达了这个遥远的、超凡脱俗的岛屿，那里的熔岩流形成了高耸的悬崖，巨大的冰山漂浮在海面上，北极熊在海岸线上徘徊。霍顿说，包括齐齐克塔尼因纽特人协会和努纳武特研究所在内的当地组织为研究人员提供了接触、建议和保护，使他们免受熊的伤害。

“This area on Baffin Island holds special importance both as sacred lands for the local communities and as a scientific window into the deep Earth,” he said.

他说:“巴芬岛上的这片地区对当地社区来说具有特殊的重要性，既是神圣的土地，也是探索地球深处的科学窗口。”

The Arctic rocks that Horton and his team investigated revealed surprisingly higher measurements of helium-3 and helium-4 than was reported by previous research, and the measurements varied among the samples they collected.

霍顿和他的团队调查的北极岩石显示，氦-3和氦-4的测量值比以前的研究报告惊人地高，而且测量值在他们收集的样本中有所不同。

“Many of the lavas are full of bright green olivine (also known as the gemstone peridot), so breaking off fresh pieces with a rock hammer was as thrilling as breaking apart geodes as a kid: each rock was a treasure to be discovered,” Horton said. “And what scientific treasures they turned out to be!”

霍顿说:“许多熔岩都充满了亮绿色的橄榄石(也被称为橄榄石宝石)，所以用岩石锤敲碎新鲜的岩石就像小时候敲开晶洞一样令人兴奋:每一块岩石都是待发现的宝藏。”“它们原来是多么珍贵的科学宝藏啊!”

Only about one helium-3 atom exists for every million helium-4 atoms, Horton said. The team measured about 10 million helium-3 atoms per gram of olivine crystals.

霍顿说，每一百万个氦-4原子中只有一个氦-3原子存在。研究小组测量了每克橄榄石晶体中大约1000万个氦-3原子。

“Our high 3He/4He measurements imply that gases, presumably inherited from the solar nebula during solar system formation, are better preserved in Earth than previously thought,” he said.

他说:“我们的高3He/4He测量表明，气体可能是在太阳系形成期间从太阳星云中继承下来的，它们在地球上的保存比以前想象的要好。”

Tracing Earth’s history

追溯地球的历史

But how did the helium-3 end up in the rocks in the first place?

但氦-3最初是如何进入岩石的呢?

The answer may begin as far back as the big bang, which, when it created the universe, also released an abundance of hydrogen and helium. These elements were incorporated into the formation of galaxies over time.

答案可能要追溯到大爆炸时期，大爆炸在创造宇宙的同时，也释放了大量的氢和氦。随着时间的推移，这些元素被合并到星系的形成中。

Scientists believe our solar system formed 4.5 billion years ago within a solar nebula. As the dust cloud collapsed in a supernova, the resulting material formed a spinning disk that eventually gave rise to our sun and the planets, according to NASA.

科学家们相信我们的太阳系是45亿年前在一个太阳星云中形成的。根据美国宇航局的说法，当尘埃云在超新星中坍塌时，产生的物质形成了一个旋转的圆盘，最终形成了我们的太阳和行星。

Helium inherited from the solar nebula likely became locked in Earth’s core as the planet formed, making the core a reservoir of noble gases. As helium-3 leaked from the core, it ascended to the surface through the mantle in the form of magma plumes that eventually erupted on Baffin Island.

随着地球的形成，从太阳星云继承下来的氦很可能被锁定在地球的核心，使核心成为稀有气体的储存库。随着氦-3从地核泄漏出来，它以岩浆柱的形式通过地幔上升到地表，最终在巴芬岛喷发。

“During the eruption, the vast majority of the gases in the magma escaped to the atmosphere,” Horton said. “Only the olivine crystals that grew prior to eruption trapped and preserved the helium from the deep Earth.”

霍顿说:“在喷发期间，岩浆中的绝大多数气体逃逸到大气中。”“只有在喷发前生长的橄榄石晶体才能捕获并保存来自地球深处的氦。”

The new research supports the idea that helium-3 is leaking from Earth’s core and has been for some time, but the researchers aren’t entirely sure when this process began.

新的研究支持了氦-3正在从地核泄漏的观点，并且已经有一段时间了，但研究人员并不完全确定这个过程是什么时候开始的。

“The lavas are about 60 million years old, and the ascent of the mantle plume took perhaps tens of millions of years,” Horton said. “So, the helium we measured in these rocks would have escaped the core perhaps 100 million years ago or possibly much earlier.”

“熔岩大约有6000万年的历史，地幔柱的上升可能花了数千万年，”霍顿说。“所以，我们在这些岩石中测量到的氦可能在1亿年前或更早的时候逃离了核心。”

Helium leaking from Earth’s core doesn’t affect our planet or have any negative implications, he said. The noble gas does not chemically react with matter, so it won’t have an impact on humanity or the environment.

他说，从地核泄漏的氦不会影响我们的星球，也不会产生任何负面影响。惰性气体不与物质发生化学反应，因此不会对人类或环境产生影响。

Next, the research team wants to investigate whether the core is a storehouse of other light elements, which could account for the why Earth’s outer core is less dense than expected.

接下来，研究小组想要调查地核是否是其他轻元素的仓库，这可以解释为什么地球外核的密度比预期的要低。

“Is the core a major repository of elements like carbon and hydrogen, which are so important in terms of planetary habitability? If so, have fluxes of these elements from the core over (Earth’s) history influenced planetary evolution? I am excited to investigate links between helium and other light elements,” Horton said. “Perhaps helium can be used to track other elements across the core-mantle boundary.”

“地核是碳和氢等元素的主要储存库吗?这些元素对行星的宜居性非常重要。”如果是这样，这些来自地核的元素在(地球)历史上的流动是否影响了行星的演化?我很高兴能研究氦和其他轻元素之间的联系，”霍顿说。“也许氦可以用来追踪穿过地核-地幔边界的其他元素。”