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新证据表明上下地幔之间相互隔离 快报文章
地球科学快报,2023年第16期
作者:  王晓晨
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Ti  Earth evolution  
科学家重新确定地球大陆形成时间 快报文章
地球科学快报,2023年第15期
作者:  王晓晨
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Pb isotope  Earth's dynamic evolution  
Science Advances:寒武纪以来地壳磷含量持续增加 快报文章
地球科学快报,2023年第10期
作者:  王立伟
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Evolution  phosphorus reservoir  
科学家基于全球氮同位素分析揭示了8亿年前地球生命演化进程 快报文章
地球科学快报,2023年第07期
作者:  王晓晨
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Nitrogen isotopes  Life evolution  
科学家首次证实地球氧同位素比率取决于地球内部热流 快报文章
地球科学快报,2023年第1期
作者:  张树良
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oxygen isotope ratios  Earth's thermal evolution  heat flow  sedimentary rock  chert  
科学家采用新的联合成像技术分析陨石以探究地球水的来源 快报文章
地球科学快报,2022年第22期
作者:  张树良
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combining neutrons and X-ray imaging  meteorite  Earth evolution  water  
研究首次揭示地球早期微生物对地球轨道周期变化的响应 快报文章
地球科学快报,2022年第21期
作者:  张树良
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microbial community  earth's orbital cycles  orbital driven paleoenvironmental changes  paleoenvironment evolution  
探索地球资源的新测绘技术 快报文章
地球科学快报,2022年第13期
作者:  王晓晨
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Thermochemical structure  Cratonic  Earth evolution  
海水中的钨同位素有助于了解地幔和大陆的共同演化 快报文章
地球科学快报,2022年第11期
作者:  王晓晨
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wolfram  geodynamic evolution  
Ice retreat in Wilkes Basin of East Antarctica during a warm interglacial 期刊论文
NATURE, 2020, 583 (7817) : 554-+
作者:  T. Blackburn;  G. H. Edwards;  S. Tulaczyk;  M. Scudder;  G. Piccione;  B. Hallet;  N. McLean;  J. C. Zachos;  B. Cheney;  J. T. Babbe
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Uranium isotopes in subglacial precipitates from the Wilkes Basin of the East Antarctic Ice Sheet reveal ice retreat during a warm Pleistocene interglacial period about 400,000 years ago.


Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth'  s past interglacial warm periods(1-3). About 400,000 years ago, during the interglacial period known as Marine Isotopic Stage 11 (MIS11), the global temperature was 1 to 2 degrees Celsius greater(2)and sea level was 6 to 13 metres higher(1,3). Sea level estimates in excess of about 10 metres, however, have been discounted because these require a contribution from the East Antarctic Ice Sheet(3), which has been argued to have remained stable for millions of years before and includes MIS11(4,5). Here we show how the evolution of(234)U enrichment within the subglacial waters of East Antarctica recorded the ice sheet'  s response to MIS11 warming. Within the Wilkes Basin, subglacial chemical precipitates of opal and calcite record accumulation of(234)U (the product of rock-water contact within an isolated subglacial reservoir) up to 20 times higher than that found in marine waters. The timescales of(234)U enrichment place the inception of this reservoir at MIS11. Informed by the(234)U cycling observed in the Laurentide Ice Sheet, where(234)U accumulated during periods of ice stability(6)and was flushed to global oceans in response to deglaciation(7), we interpret our East Antarctic dataset to represent ice loss within the Wilkes Basin at MIS11. The(234)U accumulation within the Wilkes Basin is also observed in the McMurdo Dry Valleys brines(8-10), indicating(11)that the brine originated beneath the adjacent East Antarctic Ice Sheet. The marine origin of brine salts(10)and bacteria(12)implies that MIS11 ice loss was coupled with marine flooding. Collectively, these data indicate that during one of the warmest Pleistocene interglacials, the ice sheet margin at the Wilkes Basin retreated to near the precipitate location, about 700 kilometres inland from the current position of the ice margin, which-assuming current ice volumes-would have contributed about 3 to 4 metres(13)to global sea levels.