Structure of the internal isochronous layers at Dome A, East Antarctica
Structure of the internal isochronous layers at Dome A, East Antarctica
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东南极洲 Dome A 内部等时层结构
DOI：
10.1007/s11430-010-4065-1
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发表时间：
2011-03
期刊：
影响因子：
--
通讯作者：
Li Xin
中科院分区：
文献类型：
--
作者：
Tang XueYuan;Sun Bo;Zhang ZhanHai;Zhang XiangPei;Cui XiangBin;Li Xin
穹丘A（昆仑站）被认为是一个可能找到冰芯记录的地方，可以追溯到一百万年前。由冰雷达揭示的南极冰盖内部等厚线分层是选择可用于研究古气候记录的深冰芯钻探地点的先决条件。2004/2005年，在中国第21次南极科学考察期间，在冰穹A上获得了200公里长的连续雷达剖面。剖面沿着的内部地层是从雷达探测到的地层学中得出的。等深线层的形态特征表明：（1）浅冰盖（0-500 m）内部各层总体平坦，层间距不超过50 m，局部地区有典型的向斜和背斜。(2)在冰盖表面以下500-2000 m处，各层出现“亮层”，层间距扩大到50-100 m。(3)当基底地形波长近似于冰的厚度（3公里）时，追踪的内部层，局部凸起或凹褶皱，是渐近平行于冰下地形。对于较长的地形波长（1020公里）比冰的厚度宽，层不上升和下降的基础地形。一些山峰周围的内层代表了地形上最极端的变化，受到冰下地形的强烈干扰。(4)在基底冰盖中检测到层间不连续和断裂。最后，通过将这些新信息与现有的冰厚数据相结合，我们能够选择三个潜在的地点来重建冰芯的年龄-深度关系。
Dome A (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequisite for selecting sites for deep ice core drilling that can be used for studying the paleoclimatic record. In 2004/2005, during the 21st Chinese National Antarctic Research Expedition (CHINARE 21), a 200-km long, continuous radar profile was obtained across Dome A. The internal layers along the profile were derived from the stratigraphy detected by the radar. The morphology of the isochronous layers shows that: (1) The internal layers in the shallow ice sheet (0–500 m) are generally flat, with no more than 50 m of layer intervals, and have typical synclines and anticlines in some localized regions. (2) At 500–2000 m below the surface of the ice sheet, the layers appear as “bright layers”, and the width of the layer intervals expands to 50–100 m. (3) When the basal topographic wavelengths are approximate to the thickness of the ice (3 km), the traced internal layers, with localized bumps or concave folds, are asymptotic parallel to the subglacial topography. For the longer topographic wavelengths (∼20 km) wider than the thickness of the ice, the layers do not rise and fall with the basal topography. The internal layers surrounding some mountain peaks representing the most extreme variation in the terrain are sharply disturbed by the subglacial topography. (4) Layer discontinuity and fracture were detected in the basal ice sheet. Finally, by combining this new information with that derived from existing data regarding ice thickness, we were able to select three potential sites for reconstructing the age-depth relationship of the ice core.
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影响因子：
64.8
作者：
D. H. M. Millar
通讯作者：
D. H. M. Millar
影响因子：
3.4
作者：
C. Harrison
通讯作者：
C. Harrison
影响因子：
3.2
作者：
T. Matsuoka;S. Fujita;S. Mae
通讯作者：
T. Matsuoka;S. Fujita;S. Mae
DOI：
10.3189/172756404781814591
发表时间：
2004-01-01
期刊：
ANNALS OF GLACIOLOGY, VOL 39, 2004
影响因子：
--
作者：
Frezzotti, M;Bitelli, G;Zirizzottl, A
通讯作者：
Zirizzottl, A
影响因子：
64.8
作者：
Kendrick C. Taylor;C. Hammer;R. Alley;H. Clausen;D. Dahl-Jensen;A. Gow;N. Gundestrup;J. Kipfstuh;John C. Moore;John C. Moore;E. Waddington
通讯作者：
Kendrick C. Taylor;C. Hammer;R. Alley;H. Clausen;D. Dahl-Jensen;A. Gow;N. Gundestrup;J. Kipfstuh;John C. Moore;John C. Moore;E. Waddington