研究人员在苏格兰西海岸附近的加韦勒赫群岛上发现了有关地球有史以来最大冰川期的最佳地质记录，这次冰川期发生在 7.2 亿年前。这场几乎覆盖了整个地球的大冰冻被称为 “雪球地球”，它分为两个阶段，共持续了 8000 万年。在此之后，地球上的第一个动物生命出现了。

Layers of rock can be thought of as pages of a history book – with each layer containing details of the Earth's condition in the distant past. But the critical period leading up to Snowball Earth was thought to be missing because the rock layers were eroded in the big freeze.

不同的岩石层可以被认为是一本历史书的不同页，每一层都包含了在遥远的过去地球状况的细节。但是 “雪球地球” 形成的关键时期的记录曾被认为是缺失的，因为岩石层曾在冰川期中受到侵蚀。 

Now, a new study by researchers at University College London, has revealed that the Garvellachs somehow escaped unscathed and may be the only place on Earth to have a detailed record of how the Earth entered one of the most catastrophic periods in its history, as well as what happened when the first animal life emerged when the snowball thawed.

现在，由伦敦大学学院的研究人员进行的一项新研究表明，加韦勒赫群岛不知为何毫发无损地度过了冰川期，成为了可能是地球上唯一一个详细记录了地球是如何进入其历史上最具灾难性的时期之一的地方，它也记录了当 “雪球地球” 融化、第一个动物生命出现时地球上发生了什么。

The discovery could mean that the islands may be awarded one of the biggest accolades in science: a golden spike, which is an actual spike hammered into a location that catalogues big transitions in the planet's geological history.

这一发现意味着加韦勒赫群岛有可能被授予科学界的最高荣誉之一——“金钉子”，这是一个真正的钉子，它将会被钉在加韦勒赫群岛上记载着地球的地质历史发生重大转变的位置。

词汇表

layers 层
critical period 关键时期
eroded 被侵蚀
unscathed 毫发无损地
catastrophic 灾难性的
emerged 出现
thawed 融化，解冻
accolades 荣誉，嘉奖
catalogues 记载，编入目录

阅读理解：请在读完上文后，回答下列问题。

1. What contains details of the Earth's condition in the distant past? 

2. True or False? New evidence shows that not all rock layers showing the critical period leading up to Snowball Earth are missing.

3. What two things can the rock layers in the Garvellachs tell us?

4. What is a golden spike?

答案

1. What contains details of the Earth's condition in the distant past?

Rock layers contain details of the Earth's condition in the distant past.

2. True or False? New evidence shows that not all rock layers showing the critical period leading up to Snowball Earth are missing.

True. A new study by researchers at University College London has revealed that the Garvellachs somehow escaped erosion.

3. What two things can the rock layers in the Garvellachs tell us?

The rock layers give us a detailed record of how the Earth became the Snowball Earth, and what happened when the first animal life emerged when the snowball thawed.

4. What is a golden spike?

A golden spike, as a science accolade, is an actual spike hammered into a location that catalogues big transitions in the planet's geological history.