An assessment of deep hot-water drilling as a means to undertake direct measurement and sampling of Antarctic subglacial lakes: experience and lessons learned from the Lake Ellsworth field season 2012/13
An assessment of deep hot-water drilling as a means to undertake direct measurement and sampling of Antarctic subglacial lakes: experience and lessons learned from the Lake Ellsworth field season 2012/13
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DOI：
10.3189/2014aog65a008
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发表时间：
2014-06
影响因子：
2.9
通讯作者：
M. Siegert;Keith Makinson;D. Blake;M. Mowlem;N. Ross
中科院分区：
文献类型：
--
作者：
M. Siegert;Keith Makinson;D. Blake;M. Mowlem;N. Ross
摘要2012年12月25日凌晨，一次使用专门设计的热水钻探索南极洲西部冰川下埃尔斯沃思湖的尝试被叫停。这个联合王国的项目涉及几所大学、英国南极调查局和国家海洋学中心，已经规划了10年。该项目为冰下湖泊研究制定了一个完整的蓝图，包括通过深钻进入冰下环境，通过建造探测器和沉积物取样器直接测量和取样水和沉积物，以及环境议定书，以确保清洁符合关于冰下系统管理和保护的国际协定。在主钻孔未能与地下水腔连通后，钻探停止，该水腔是在2040多个小时内形成的。如果没有这一联系，就没有足够的水继续向下钻探到水面以下3000米的湖泊。返回英国后，对该方案进行了外部审查，以正式评估实地工作失败的原因，并就成功所需的修改提出建议。根据这一审查，埃尔斯沃思湖方案制定了一条沿着可以开发第二次探索该湖的途径。这里详细介绍了埃尔斯沃思湖现场实验，导致其失败的情况和所需的更正。热水钻井仍然被认为是确保清洁进入冰下环境的唯一可行方案。然而，从埃尔斯沃思湖的经验中吸取的教训是巨大的，并表明，要在厚冰层（>2公里）下成功地进行未来的冰下湖泊研究，必须在技术和方法上取得相当大的进展。
Abstract In the early hours of 25 December 2012, an attempt to explore Subglacial Lake Ellsworth, West Antarctica, using a specially designed hot-water drill, was halted. This UK project, involving several universities, the British Antarctic Survey and the National Oceanography Centre, had been in planning for 10 years. The project developed a full blueprint for subglacial lakes research, involving access to the subglacial environment through deep drilling, direct measurement and sampling of water and sediment by the construction of a probe and sediment corer, and environmental protocols to ensure cleanliness in line with international agreements on stewardship and protection of subglacial systems. Drilling was ceased after the main borehole failed to link with a subsurface cavity of water, built up over ∽40 hours. Without this link, insufficient water was available to continue drilling downwards to the lake, ∽3000 m beneath the surface. On return to the UK, an external review of the programme was undertaken to formally assess the reasons for the fieldwork failure, and to make recommendations on the modifications necessary for success. From this review, the Lake Ellsworth programme formulated a pathway along which a second attempt to explore the lake can be developed. Here details of the Lake Ellsworth field experiment, the circumstances that led to its failure and the corrections required are presented. Hot-water drilling is still regarded as the only feasible scheme for assuring clean access to the subglacial environment. The lessons learned from the Lake Ellsworth experience are substantial, however, and demonstrate that considerable technological and methodological advances are necessary for successful future research on subglacial lakes beneath thick (>2 km) ice.