Antarctic subglacial groundwater: a concept paper on its measurement and potential influence on ice flow
Antarctic subglacial groundwater: a concept paper on its measurement and potential influence on ice flow
复制标题
DOI：
10.1144/sp461.8
复制
发表时间：
2017-05
期刊：
影响因子：
--
通讯作者：
M. Siegert;B. Kulessa;M. Bougamont;P. Christoffersen;K. Key;Kristoffer R. Andersen;A. Booth;A. Smith
中科院分区：
文献类型：
--
作者：
M. Siegert;B. Kulessa;M. Bougamont;P. Christoffersen;K. Key;Kristoffer R. Andersen;A. Booth;A. Smith
摘要南极地下水丰富吗？它调节冰流吗？探究这个问题很重要，因为冰流是通过在潮湿的冰碛物上滑动而流动的。因此，注入冰流床的水会影响冰盖的动态，并可能导致海平面上升。人们认识到冰碛物和冰碛物所源自的沉积盆地都是多孔的，可能含有与冰下界面系统相互作用的移动的地下水的储层。根据最近的数值模拟，多达一半的水可用于基础润滑，水文强迫和冰盖响应之间的时间滞后长达千年，可能被忽略了冰流模型。在这里，我们回顾证据支持南极地下水，并提出如何可以测量，以确定在何种程度上它调制冰流。我们提出了新的震电测深冰下冰碛，和大地电磁和瞬变电磁的冰下地下水库的正演模型。我们证明，多方面的综合地球物理数据集可以检测，描绘和量化冰下沉积盆地的地下水含量，并有可能监测冰下冰碛层之间的地下水交换率。因此，本文描述了一个新的冰川学研究领域，以及它应该如何在未来的进展。
Abstract Is groundwater abundant in Antarctica and does it modulate ice flow? Answering this question matters because ice streams flow by gliding over a wet substrate of till. Water fed to ice-stream beds thus influences ice-sheet dynamics and, potentially, sea-level rise. It is recognized that both till and the sedimentary basins from which it originates are porous and could host a reservoir of mobile groundwater that interacts with the subglacial interfacial system. According to recent numerical modelling, up to half of all water available for basal lubrication, and time lags between hydrological forcing and ice-sheet response as long as millennia, may have been overlooked in models of ice flow. Here, we review evidence in support of Antarctic groundwater and propose how it can be measured to ascertain the extent to which it modulates ice flow. We present new seismoelectric soundings of subglacial till, and magnetotelluric and transient electromagnetic forward models of subglacial groundwater reservoirs. We demonstrate that multifaceted and integrated geophysical datasets can detect, delineate and quantify the groundwater contents of subglacial sedimentary basins and, potentially, monitor groundwater exchange rates between subglacial till layers. The paper thus describes a new area of glaciological investigation and how it should progress in future.