Quantifying Wedge‐Ice Volumes in Yedoma and Thermokarst Basin Deposits
Quantifying Wedge‐Ice Volumes in Yedoma and Thermokarst Basin Deposits
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DOI：
10.1002/ppp.1810
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发表时间：
2014-07
影响因子：
5
通讯作者：
M. Ulrich;G. Grosse;J. Strauss;Lutz Schirrmeister
中科院分区：
文献类型：
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作者：
M. Ulrich;G. Grosse;J. Strauss;Lutz Schirrmeister
楔冰体积(Wiv)是评估富含冰的永久冻土地貌对融化的反应和量化深永久冻土土壤碳清单的关键因素。本文介绍了西伯利亚和阿拉斯加四个研究区晚更新世伊多玛沉积和全新世热岩溶盆地沉积的WIV计算方法。利用非常高分辨率(0.5米/像素)的卫星图像(Worldview-1和GeoEye-1)，在不同的景观单元上绘制了冰-楔形多边形和热岩溶丘陵(Baydzherakh)图案。在地理信息系统(GIS)环境中，自动创建Thiessen多边形以重建残留的冰楔多边形网络，并使用现场数据和已公布的冰楔尺寸数据生成区分表生和同生冰楔几何形状的三维地下模型。结果显示，在研究地点之间和某些地形单元内，WIV存在显著差异。经计算，伊多玛矿床的最大体积百分比为31.4%~63.2%，热岩溶盆地矿床的最大体积百分比为6.6%~13.2%。版权所有©2014 John Wiley&Sons，Ltd.
Wedge‐ice volume (WIV) is a key factor in assessing the response of ice‐rich permafrost landscapes to thaw and in quantifying deep permafrost soil carbon inventories. Here, we present a method for calculating WIV in late Pleistocene Yedoma deposits and Holocene thermokarst basin deposits at four study areas in Siberia and Alaska. Ice‐wedge polygons and thermokarst mound (baydzherakh) patterns were mapped on different landscape units using very high‐resolution (0.5 m/pixel) satellite imagery (WorldView‐1 and GeoEye‐1). In a geographic information system (GIS) environment, Thiessen polygons were automatically created to reconstruct relict ice‐wedge polygonal networks, and field and published data on ice‐wedge dimensions were used to generate three‐dimensional subsurface models that distinguish between epi‐ and syngenetic ice‐wedge geometry. The results reveal significant variations in WIV between the study sites and within certain terrain units. Calculated maximum WIV ranges from 31.4 to 63.2 vol% for Yedoma deposits and from 6.6 to 13.2 vol% for thermokarst basin deposits. Copyright © 2014 John Wiley & Sons, Ltd.