新西兰位于一座古老火山喷发出的巨大熔岩泡的顶端

新西兰位于一座古老火山喷发出的巨大熔岩泡的顶端

Scientists may have found the most compelling evidence yet that the Earth's molten core belches out blobs of lava that eventually find their way to the surface.

科学家们可能已经发现了迄今为止最令人信服的证据，证明地球熔融的核心喷出的熔岩最终会到达地表。

In fact, the evidence is hard to ignore. It’s New Zealand.

事实上，证据不容忽视。这就是新西兰。

About 120 million years ago, a vast, unbroken volcanic plateau formed beneath the sea. (Photo: verticalberto/Shutterstock)

In a study published in Science Advances, researchers from the Victoria University of Wellington suggest the country is perched on a vast bubble of lava produced by an ancient volcano.

在发表在《科学进展》杂志上的一项研究中，来自惠灵顿维多利亚大学的研究人员认为，这个国家栖息在一个由古代火山喷发的巨大熔岩泡上。

Now, if you’re in New Zealand, there’s no reason to panic. Or even tread lightly. That lava has had more than 100 million years to cool and harden. In fact, as the researchers point out, those ancient volcanic eruptions likely created an undersea plateau during the Cretaceous Period. That India-sized plateau eventually fragmented, with a big chunk becoming the box spring for New Zealand. That lava-cooled slab would become known as the Hikurangi Plateau.

现在，如果你在新西兰，没有理由恐慌。甚至可以随意走动。熔岩冷却硬化的时间超过1亿年。事实上，正如研究人员指出的那样，那些古老的火山喷发可能在白垩纪形成了海底高原。印度大小的高原最终分裂，其中一大块成为了新西兰的方块弹簧。这个熔岩冷却的板块被称为Hikurangi高原。

“Our results show that New Zealand sits atop the remains of such an ancient giant volcanic plume,” the researchers explain in The Conversation. “We show how this process causes volcanic activity and plays a key role in the workings of the planet.”

研究人员在对话中解释说:“我们的研究结果表明，新西兰位于如此古老的巨大火山烟羽的遗迹之上。我们展示了这一过程是如何导致火山活动的，并在地球的运转中发挥了关键作用。”

Sitting atop a powerful force

坐落在一股强大的力量之上

Their research paints a fascinating picture of the heavy forge at the heart of our planet. There’s a long-standing theory that the Earth’s interior churns “like a lava lamp, with buoyant blobs rising as plumes of hot mantle rock from near Earth's core,” the researchers note in the article.

他们的研究描绘了一幅地球中心的重熔炉的迷人图画。有一种长期存在的理论认为，地球内部的搅动“就像一盏熔岩灯，有浮力的水滴从靠近地球核心的热地幔岩柱中升起，”研究人员在文章中写道。

As those plumes creep toward the surface, the theory suggests, they melt — and volcanic eruptions ensue. But evidence supporting that theory was scant — until scientists took a closer look at New Zealand’s underpinnings.

该理论认为，当这些烟羽慢慢向地表移动时，它们就会融化，然后火山就会爆发。但支持这一理论的证据很少——直到科学家们更仔细地观察了新西兰。

Specifically, they measured the speed of seismic pressure waves moving through rocks beneath the Hikurangi Plateau. Those waves, known as P-waves, are essentially sound waves. And they move at a consistent and measurable speed through the planet’s roiling interior. But they move more slowly when travelling vertically outward, as opposed to horizontally in every direction.

具体来说，他们测量了地震压力波在Hikurangi高原下穿过岩石的速度。这些波被称为p波，本质上是声波。它们以一致的、可测量的速度穿过地球内部的漩涡。但在垂直向外移动时，它们的移动速度要慢一些，而不是水平向各个方向移动。

That speed difference helped researchers determine the staggering scope of the superplume beneath New Zealand. The research also hints at the even more vast, unbroken plateau that once stretched beneath the sea.

这种速度差异帮助研究人员确定了新西兰地下超级地幔柱的惊人范围。这项研究还暗示了曾经延伸到海底的更广阔、更完整的高原。

"The extraordinary thing is that all these plateaus were once connected, making up the largest volcanic outpouring on the planet in a region over 2,000 km across,” the researchers note. "The associated volcanic activity may have played an important role in Earth history, influencing the planet's climate and also the evolution of life by triggering mass extinctions.

研究人员指出:“不同寻常的是，所有这些高原曾经连接在一起，形成了地球上最大的火山喷发区，这个区域横跨2000多公里。相关的火山活动可能在地球历史上扮演了重要的角色，影响了地球的气候，也引发了大规模的物种灭绝，从而影响了生命的进化。”

"It is an intriguing thought that New Zealand now sits on top of what was once such a powerful force in the Earth."

“这是一个有趣的想法，新西兰现在坐落在地球上曾经如此强大的力量之上。”