Visual stratigraphy of the North Greenland Ice Core Project (NorthGRIP) ice core during the last glacial period
Visual stratigraphy of the North Greenland Ice Core Project (NorthGRIP) ice core during the last glacial period
复制标题
末次冰期北格陵兰冰芯项目（NorthGRIP）冰芯的可视地层学
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
R. Röthlisberger
中科院分区：
文献类型：
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作者：
A. Svensson;S. W. Nielsen;S. Kipfstuhl;S. Johnsen;J. Steffensen;M. Bigler;U. Ruth;R. Röthlisberger
[1]北格陵兰冰芯项目(北格陵兰冰芯项目)冰芯(75.1�N，42.3�W)在1330m至3085m基岩的深度段获得了连续的高分辨率数字图像记录。冰芯地层在整个冰期都清晰可见，最频繁和最明亮的可见层出现在最冷的事件期间。在2600米以下，水平分层非常规则；在此深度以下，分层中开始出现微小的不规则性，而在2800米以下，视觉地层变得更加不确定，可能是因为穿透到气候较温暖的冰中。视觉地层学与化学杂质和尘埃的高分辨率连续记录的对比显示出高度的相关性，这表明可见层是由这些杂质造成的。使用了一种新的方法，通过对剖面中最突出的可见层进行频率分析，从视觉地层学记录中自动确定年层厚度。这一结果为NorthGRIP时间尺度模型提供了有力的支持。
[1] A continuous high-resolution record of digital images has been obtained from the North Greenland Ice Core Project (NorthGRIP) ice core (75.1� N, 42.3� W) in the depth interval from 1330 m to the bedrock at 3085 m. The ice core stratigraphy is clearly visible throughout the glacial period with the most frequent and brightest visible layers appearing during the coldest events. Down to a depth of 2600 m the horizontal layering is very regular; below this depth, small irregularities in the layering start to appear, and below 2800 m the visual stratigraphy becomes more uncertain, perhaps because of penetration into climatically warmer ice. Comparison of the visual stratigraphy with high-resolution continuous records of chemical impurities and dust reveals a high degree of correlation, which indicates that the visible layers are caused by these impurities. A new approach is used to automatically determine annual layer thicknesses from the visual stratigraphy record by carrying out a frequency analysis of the most prominent visible layers in the profile. The result gives strong support for the NorthGRIP timescale model.