一旦超級火山噴發 人類只有一年的時間逃命

If a super-eruption were to occur, the blast would launch enough ash into the atmosphere to disrupt weather for years to follow, potentially causing famine, health crisis, and global civil unrest.

如果超級火山噴發即將發生，那麼該爆炸將噴射出足夠多的火山灰到大氣之中，從而擾亂接下來多年的天氣，有可能會造成饑荒、健康危機和全球動亂。

And leading up to the catastrophic event, the world would have just one year to prepare.

而在迎來這一悲慘事件之前，人類僅僅只有一年的時間來準備應對。

Researchers have determined this based on a microscopic analysis of quartz crystals in pumice from the Bishop Tuff in California, the site of a super-eruption 760,000 years ago.

通過對加利福尼亞主教凝灰岩（76萬年前此地曾發生過一場超級火山噴發）浮石中的石英晶體進行顯微分析，研究者們確定了這一結論。

The ancient super-eruption in eastern California formed the Long Valley Caldera – a feature that is nearly 20 miles long and 11 miles wide.

古代東加尼福利亞這場超級火山噴發形成了長谷火山口--約20英里長，11英里寬。

In the study, the researchers from Vanderbilt University and the University of Chicago analyzed dozens of small quartz crystals, remnants from the original underground magma, from the Bishop Tuff.

在這項研究中，來自範德堡大學和芝加哥大學的研究者們分析了幾十塊小石英晶體，這些石英晶體採自主教凝灰岩，是地下岩漿噴射而出後的殘餘物質。

Quartz crystals have distinctive rims, they explain in a paper published to the journal Plos One, and are rich in titanium. Along with this, they are bright in cathodoluminescence, which allowed them to make high-resolution measurements of variation in the titanium, providing detailed insight on the transition from pre-eruptive crystallization to the decompression and crystallization at the time of the blast.

研究者們在《Plos One》期刊上發表了一篇論文，解釋說這些石英晶體有不同的輪輞，並且富含鈦。除此之外，這些石英晶體還被置於陰極射線的照射下，從而使得研究者們可以得到鈦物質變動的高精確測量，進而可以詳細地觀察到噴發前的晶體減壓、在爆炸時結晶的轉化過程。

This analysis helped to determine rim growth times and growth rates – revealing that these processes largely occurred in a span of less than a year.

這項分析能夠幫助確定輪輞的生長時間和生長率--而分析結果顯示，這些過程大部分都發送在不到一年的時間裏。

'Maximum rim growth times span from approximately 1 minute to 35 years, with a median of approximately 4 days,' the authors wrote. 'More than 70 percent of rim growth times are less than 1 year, showing that quartz rims have mostly grown in the days to months prior to eruption... Growth took place under conditions of high supersaturation suggesting that rim growth marks the onset of decompression and the transition from pre-eruptive to syn-eruptive conditions.'

作者們寫道：“大部分輪輞的生長時間都在約1分鐘到35年之間，其中中位數大約是4天。超過70%輪輞的生長時間不足1年，這表明石英輪輞生長的時間大多截止到超級火山噴發前幾個月。輪輞生長只會發生在高度飽和的情況下，這表明輪輞的生長記錄下了減壓的開始時間，以及從爆發前到爆發時的情況變化。”

It takes tens of thousands of years for the crust to generate enough eruptible magma, but once formed, these unstable magma bodies only last for centuries to a few millennia. As the decompression occurs, the magma body would likely be expanding as well, having detectable effects at the surface.

地殼聚集足夠噴發的岩漿需要數萬年的時間，但是一旦準備完畢，這些不穩定的岩漿體就只會在地殼內存在幾百年到幾千年的時間。一旦減壓作用發生，岩漿體就有可能膨脹，並在地表產生明顯的影響。