科學家分析通過地球深處的地震波，似乎證實了實驗顯示的一種可能性：地表以下640公里處的地幔鎖住一大片海洋。這些水不是液態，而是鎖在如此深度所產生極端壓力下的礦物當中。

The finding suggests that processes that occur in the shallower mantle and that cause volcanoes and related activity at the surface are also occurring farther down.

這項發現意味，發生在較淺層地幔，在地表引發火山與相關活動的過程也會在更深處發生。

“It’s a new view of the structure of this part of the earth,” said Brandon Schmandt, a geophysicist at the University of New Mexico and an author of a recent paper in the journal Science describing the research.

新墨西哥大學地球物理學家席曼特最近在「科學」期刊發表報告說明這項研究。他說：「這是對地球這個部位結構的新見解。」

The work also adds credence to the idea that the earth’s water accumulated in the interior during the planet’s formation, rather than arriving later through the bombardment of icy comets. In this view, water bound up in minerals in the mantle, the 2,900-kilometer-thick layer between the thin crust and the hot metallic core, degassed over time and reached the surface.

這項研究也使以下看法更具可信性：地球的水是地球形成期間在其內部累積而得，而非冰質彗星後來撞擊地球帶來的。依此理論，經過相當時間之後，鎖在地幔礦物中的水脫除氣體，來到地表。地幔是介於薄質地殼與含金屬滾熱地球核心之間的2900公里厚地層。

The scientists studied a part of the mantle called the transition zone, from about 480 kilometers to 640 kilometers deep. The ability of this zone to contain water — and apparently to retain a lot of it — “may have something to do with stabilizing or buffering the size of the oceans,” said Steven D. Jacobsen, a mineralogist at Northwestern University in Illinois, another author of the paper. “It may be fortunate that the earth’s interior can act like a sponge.”

科學家研究深度介於480公里與640公里之間名為過渡區域的地幔。共同撰寫研究報告的伊利諾州西北大學礦物學家雅各森表示，這個區域具備含水與保水的能力，而且顯然是極大量的水，這可能與「穩定或緩衝大面積海洋有關。地球內部有如一塊海綿。這可能是我們幸運之處」。

Dr. Jacobsen synthesizes deepearth minerals by replicating the extreme pressures that exist hundreds of kilometers below the surface. Over the years when he has made a blue mineral called ringwoodite, which is ubiquitous in the transition zone, it has formed with water. But that was just lab work, Dr. Jacobsen said, adding, “We haven’t known whether it could happen down there.”

雅各森複製地表以下數百公里處的極端壓力，進而合成地球深處的礦物。在他製出過渡區隨處可見的藍色礦物尖晶橄欖石的多年間，水亦同時形成。不過他表示這只是實驗結果，「還不知道會不會也在地球深處發生」。

Dr. Schmandt analyzed seismic data from the USArray project, in which 400 mobile seismometers have been deployed to create high-resolution images of the mantle. The analysis showed signs of melting in the transition zone, in areas where convection was causing the mantle to flow downward.

席曼特分析來自地震台陣計畫的地震資料。該計畫部署400個移動式地震儀，以呈現高解析度的地幔影像。分析顯示在對流作用導致地幔向下流動的過渡區，有融化徵象。

Melting of the mantle occurs close to the surface, creating the magma that is responsible for volcanic hot spots around the world. The process is called dehydration melting, because as parts of the mantle slide deeper at places where the earth’s tectonic plates meet, the increasing pressure causes minerals in the mantle to release their water, lowering the melting temperature. But finding evidence of melting much farther down, as Dr.

地幔融化發生在接近地表的區域，產生的岩漿與全球各地的滾熱火山景象有關。這種過程名為脫水融化，因為隨著地幔滑向地球板塊相會所在的地球深處，壓力不斷增加導致地幔當中的礦物釋出水分，進而降低融化的溫度。

Schmandt did, was difficult to explain “unless you invoke water,” Dr. Jacobsen said.

雅各森表示，誠如席曼特曾經做的嘗試，「除非有水」，很難找到更深處融化的相關證據。

Their work suggests that what happens deep in the mantle is similar to what happens close to the surface, the researchers said. “You end up having a mushy rock,” Dr. Jacobsen said.

雅各森說：「結果是糊狀的岩石。」科學家試圖瞭解地球深處的動力學如何影響地表。這項研究是其中一環。

The work is all part of trying to understand how the dynamics of the deep earth affect what happens at the surface.

研究人員說，研究顯示，地幔深處的情況與接近地表處類似。

“We’re trying to connect the rock cycles — i.e., plate tectonics — with water cycles,” Dr. Jacobsen said. “The more we look, the deeper it goes.”

雅各森說：「我們試圖連結岩石循環（即板塊構造）與水的循環。我們探究越多，走得越深。」

通縮隱約逼近；反歐盟的民粹主義聲勢浩大；失業率逼近歷史高點。

The euro zone is a club that few potentially eligible countries are eager to join. But on July 1, if all goes according to plan, shops in Lithuania will start accepting euros and the country will cede sovereignty over monetary policy to the European Central Bank.

歐元區是個潛在合格國家幾乎都不急於加入的俱樂部。然而如果一切順利，立陶宛明年元旦就會開始採用歐元，同時將有關貨幣政策的自主權交給歐洲中央銀行。

Lithuania may be the last new member of the euro zone until the end of the decade. Of the seven other European Union countries still planning to join someday, not one meets all the criteria for economic performance, budget discipline or central bank independence, according to a report issued by the European Central Bank. After six years of crisis and near-record unemployment in the region, political leaders feel little pressure to join the euro zone.

立陶宛可能是2020年之前，最後一個加入歐元區的國家。目前有七個歐盟國家仍然計畫有朝一日加入歐元區，然而根據歐洲央行公布的一項評估報告，沒有一國在經濟表現、預算紀律及央行獨立性方面符合所有要求。這個區域歷經連續六年的危機與接近歷史高點的嚴重失業之後，各國政治領袖幾乎沒有加入歐元區的壓力。

In theory, all members of the European Union are required to strive for euro membership, excluding Britain and Denmark. To qualify, countries must make changes to their laws and economies, such as by loosening rules on hiring and firing.

理論上，除了英國與丹麥，歐盟的其他會員國必須為加入歐元區而努力。為達成目標，各國必須修法並改造經濟，例如放寬有關聘用與解雇勞工的法律。

The European Union countries that remain outside the currency group, such as Sweden and the Czech Republic, are not showing much enthusiasm for doing that. The others are Bulgaria, Hungary, Croatia, Poland and Romania.

迄未加入歐元區的歐盟國，如瑞典與捷克，對於從事於這些努力顯得意興闌珊。其他幾國是保加利亞、匈牙利、克羅埃西亞、波蘭與羅馬尼亞。

“The countries that are left still have a lot to do structurally,” said Mujtaba Rahman, of Eurasia Group, a consulting firm.

顧問公司「歐亞集團」的拉曼說：「仍未加入歐元區的各國，在結構性改革方面還有許多事情要做。」

A case in point is Poland. With more than 38 million people and one of the fastest-growing economies in the European Union, Poland would be a welcome addition to the euro club. But the government, facing opposition in Parliament, has not put a priority on bringing its central bank laws into harmony with euro zone standards.

波蘭就是一個例子。波蘭人口超過3800萬，是歐盟經濟成長最快速的國家之一，如果加入歐元俱樂部，必會受到歡迎。然而波蘭政府因在國會遭遇阻力所致，並未把修改有關波蘭央行的法律，使其符合歐元區標準的工作列為優先事項。

“They have mixed feelings about joining the euro,” Mr. Rahman said. “It’s more a political constraint than an economic one.”

拉曼說：「他們對加入歐元區的選項懷有複雜的感覺。此事涉及的政治束縛大於經濟層次。」

The euro remains appealing to the smaller countries like Lithuania, a nation of three million people whose gross domestic product was an estimated $67 billion in 2013.

歐元對小國如立陶宛仍然具有吸引力。立陶宛全國人口約僅300萬，2013年的國內生產毛額約670億美元。

Lithuania’s prime minister, Algirdas Butkevicius, suggested that link to Brussels through the single currency would be beneficial in the wake of Russian assertiveness in Ukraine.

立陶宛總理巴特基維休斯表示，俄羅斯最近干預烏克蘭事務之後，立陶宛透過加入歐元區而與布魯塞爾當局產生關聯將對立陶宛有利。

The sacrifice of membership is that countries can no longer allow their currencies to depreciate as a way of making their exports more competitive. This is on display in Greece. Without their own currency to absorb the shock of the debt crisis, many Greeks have had to accept steep wage cuts.

各國加入歐元區必須付出的代價是，再也無法為了提高出口競爭力而讓貨幣貶值。希臘目前就處於這種情況之下。在無法以本國貨幣吸收債務危機震波的情況下，許多希臘人只能眼睜睜看著他們的薪資大幅縮水。

Lithuania has tied its currency, the litas, to the euro for a decade. So it is will not really give up any room to maneuver. On the contrary, use of the euro relieves the country’s central bank of the stress of defending the value of the litas on currency markets.

立陶宛將它的貨幣立塔與歐元掛勾已經10年。如此局面下，它不會真正放棄任何轉圜操作的空間。相反的，採用歐元足以使立陶宛央行得免承受必須在貨幣市場捍衛立塔的壓力。

Parties that are hostile to the European Union or want to abandon the euro were the big winners in elections to the European Parliament in May. That was true even in France and Germany, the bloc’s two largest members.

反對歐盟或有意放棄歐元的政黨是五月歐洲議會選舉的大贏家。即使在歐元區前兩大會員國法國與德國也是如此。

Even in Lithuania, a poll last year showed that opponents of euro membership outnumbered supporters by a wide margin.

即使在立陶宛，根據去年的一項民調，反對改用歐元的受訪者也遠多於贊成者。

European leaders cited Lithuania as proof that the euro remained alluring and as confirmation of the progress made to shore up the euro after six years of turmoil that nearly sank the project.

歐洲領袖以立陶宛為例證明歐元仍然具有吸引力，也以此例證明在歐元計畫險些毀於持續六年的動盪之後，力保歐元的努力已取得實質進展。

The move, Mr. Butkevicius said, would mean a “better life for all the residents of the country.”

巴特基維休斯說，踏出這一步，將意味「我國全體國民日子會變得更好」。