配合最新的觀測資料，科學(xué)家在南極厚冰之下，找到兩個(gè)大小可媲美南極第一大湖Vostok的冰下湖泊。
從1970年首次找到冰下湖的證據(jù)后，至今陸續(xù)發(fā)現(xiàn)南極大陸有超過145個(gè)冰下湖泊的存在。最新確認(rèn)的兩大湖：90°E湖與Sovetskaya湖，是由美國哥倫比亞大學(xué)科學(xué)家Robin E. Bell領(lǐng)導(dǎo)的研究小組，利用最新的衛(wèi)星影像、測高與透冰雷達(dá)資料，首次估算出它們的大小及深度，結(jié)果發(fā)表在2月份的Geophysical Research Letters期刊上。
這兩大湖被埋在平均大約4000公尺厚的冰層下，90°E湖面積約有2000平方公里，相當(dāng)于臺(tái)北縣的面積大??；Sovetskaya湖略小、約1600平方公里。再佐以重力資料，估計(jì)出兩湖的水深均至少有900公尺。從兩湖的深度與狹長形狀判斷，科學(xué)家認(rèn)為它們很可能是蓄積在古老的斷層裂隙中，而且可以維持水深10~35百萬年之久，甚至還能孕育獨(dú)特的生態(tài)系。
目前俄羅斯的科學(xué)家正在進(jìn)行第一大湖Vostok的鉆探計(jì)畫，預(yù)計(jì)在2007年可以鉆透3600公尺左右的冰層，并取得湖水。里頭到底有什么？科學(xué)家正熱切的期待中。
Frozen Land O' Lakes By Mason Inman ScienceNOW Daily News 31 January 2006
A new survey of eastern Antarctica has revealed a surprising find： two lakes buried beneath a 4-kilometer-thick ice sheet that rival the famous Lake Vostok in size. The lakes may hold exotic life， and their position along ancient fault lines could shed light on how a nearby mountain range formed.
Earth scientists have so far spied about 145 subglacial lakes in Antarctica. Sandwiched between the ice above and bedrock below， the lakes stay liquid due to a combination of geothermal heat and the crushing pressure of the ice sheet. Lake Vostok， by far the largest of these lakes， is well-mapped， and a Russian team is now drilling through its ice cap in hopes of finding life inside. But scientists know little about most of the region's lakes， spotted only from sparse radar surveys.
A team led by geologist Robin Bell and glaciologist Michael Studinger， both at Columbia University's Lamont-Doherty Earth Observatory in Palisades， New York， revisited two hidden bodies of water glimpsed in earlier surveys. To conduct a more thorough analysis of the lakes， named 90°E and Sovetskaya， the team drew on a suite of data including new satellite images and decades-old gravity measurements， which use differences in the density of ice and water to gauge a lake's depth.
The study found that the lakes are second in size only to Lake Vostok and are nestled in deep depressions. At 2000 square kilometers， 90°E is roughly half the size of Rhode Island and reaches roughly a kilometer deep——about the same as Vostok. Sovetskaya is almost as large， at 1400 square kilometers， and likely as deep. The lakes' depths and the rugged terrain surrounding them suggest that they lie in crevasses along ancient faults， long dormant. Because the depressions that cradle the lakes are so large and deep， the researchers argue the lakes have likely stayed stable through climate changes and have been there since Antarctica was warm and rainy， more than 35 million years ago. If so， this may increase the chances that they harbor life， the team reports in the February issue of Geophysical Research Letters.
The idea that a lot of subglacial lakes form along faults is "very likely to be correct，" says glaciologist Garry Clarke of the University of British Columbia in Vancouver， Canada. If this bears out， he adds， "you could use the location of the lakes to map stripes across Antarctica and decide where the tectonic features are." That could help researchers understand mysteries such as the Gamburtsev Mountains， which do not appear to have been shaped by the tectonic activity that helped form other major mountain ranges.
從1970年首次找到冰下湖的證據(jù)后，至今陸續(xù)發(fā)現(xiàn)南極大陸有超過145個(gè)冰下湖泊的存在。最新確認(rèn)的兩大湖：90°E湖與Sovetskaya湖，是由美國哥倫比亞大學(xué)科學(xué)家Robin E. Bell領(lǐng)導(dǎo)的研究小組，利用最新的衛(wèi)星影像、測高與透冰雷達(dá)資料，首次估算出它們的大小及深度，結(jié)果發(fā)表在2月份的Geophysical Research Letters期刊上。
這兩大湖被埋在平均大約4000公尺厚的冰層下，90°E湖面積約有2000平方公里，相當(dāng)于臺(tái)北縣的面積大??；Sovetskaya湖略小、約1600平方公里。再佐以重力資料，估計(jì)出兩湖的水深均至少有900公尺。從兩湖的深度與狹長形狀判斷，科學(xué)家認(rèn)為它們很可能是蓄積在古老的斷層裂隙中，而且可以維持水深10~35百萬年之久，甚至還能孕育獨(dú)特的生態(tài)系。
目前俄羅斯的科學(xué)家正在進(jìn)行第一大湖Vostok的鉆探計(jì)畫，預(yù)計(jì)在2007年可以鉆透3600公尺左右的冰層，并取得湖水。里頭到底有什么？科學(xué)家正熱切的期待中。
Frozen Land O' Lakes By Mason Inman ScienceNOW Daily News 31 January 2006
A new survey of eastern Antarctica has revealed a surprising find： two lakes buried beneath a 4-kilometer-thick ice sheet that rival the famous Lake Vostok in size. The lakes may hold exotic life， and their position along ancient fault lines could shed light on how a nearby mountain range formed.
Earth scientists have so far spied about 145 subglacial lakes in Antarctica. Sandwiched between the ice above and bedrock below， the lakes stay liquid due to a combination of geothermal heat and the crushing pressure of the ice sheet. Lake Vostok， by far the largest of these lakes， is well-mapped， and a Russian team is now drilling through its ice cap in hopes of finding life inside. But scientists know little about most of the region's lakes， spotted only from sparse radar surveys.
A team led by geologist Robin Bell and glaciologist Michael Studinger， both at Columbia University's Lamont-Doherty Earth Observatory in Palisades， New York， revisited two hidden bodies of water glimpsed in earlier surveys. To conduct a more thorough analysis of the lakes， named 90°E and Sovetskaya， the team drew on a suite of data including new satellite images and decades-old gravity measurements， which use differences in the density of ice and water to gauge a lake's depth.
The study found that the lakes are second in size only to Lake Vostok and are nestled in deep depressions. At 2000 square kilometers， 90°E is roughly half the size of Rhode Island and reaches roughly a kilometer deep——about the same as Vostok. Sovetskaya is almost as large， at 1400 square kilometers， and likely as deep. The lakes' depths and the rugged terrain surrounding them suggest that they lie in crevasses along ancient faults， long dormant. Because the depressions that cradle the lakes are so large and deep， the researchers argue the lakes have likely stayed stable through climate changes and have been there since Antarctica was warm and rainy， more than 35 million years ago. If so， this may increase the chances that they harbor life， the team reports in the February issue of Geophysical Research Letters.
The idea that a lot of subglacial lakes form along faults is "very likely to be correct，" says glaciologist Garry Clarke of the University of British Columbia in Vancouver， Canada. If this bears out， he adds， "you could use the location of the lakes to map stripes across Antarctica and decide where the tectonic features are." That could help researchers understand mysteries such as the Gamburtsev Mountains， which do not appear to have been shaped by the tectonic activity that helped form other major mountain ranges.