Challenges and experiences in drilling ice-proximal sites
Ice-proximal drill cores from continental shelves and near-margin continental rises contain important records of regional ice stream and outlet glacier advance and retreat processes and provide, therefore, key data for understanding and reconstructing ice sheet dynamics. However, drilling at ice-pro...
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| Format: | Conference Object |
| Language: | unknown |
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2018
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| Online Access: | https://epic.awi.de/id/eprint/47722/ https://hdl.handle.net/10013/epic.fa7270c3-a2fe-474a-b7ce-d41d6e14015f |
| Summary: | Ice-proximal drill cores from continental shelves and near-margin continental rises contain important records of regional ice stream and outlet glacier advance and retreat processes and provide, therefore, key data for understanding and reconstructing ice sheet dynamics. However, drilling at ice-proximal sites, specially on the shelves, has its particular challenges and risks. DSDP Leg 28 (Ross Sea) was the first and ODP Legs 113 (Weddell Sea), 119/188 (Prydz Bay), 151 (Spitzbergen/Fram Strait), 152/163 (SE Greenland margin), 178 (Ant. Peninsula) were the next follow-up ship-based scientific deep-drilling expeditions to polar continental margins. They all had a varying degree of failure and success. More advanced drilling technology on JR and smarter strategies helped enlarge the success of IODP Expeditions 318 (Wilkes Land margin) and 374 (Ross Sea). With our first multi-barrel seabed drilling expedition to an Antarctic shelf (Amundsen Sea), we could demonstrate that MeBo, or a similar seabed drilling device, is a viable and low-cost tool for shallow drill cores at particular sites on the shelf that are beyond the penetration depths of conventional coring. Yet, the lack of continuous core recovery as well as the sea-ice and iceberg risk remain as strongest challenge for all ship-based drilling expeditions. This presentation will summarize the challenges and experiences from past ice-proximal polar drilling expeditions. I will explain the various issues we have been discussing with IODP to mitigate the risks to prepare for the upcoming IODP Expedition 379 to the Amundsen Sea Embayment (early 2019), where many of the science objectives, stratigraphic targets and challenges are closely related to those of the IODP proposal #909 to the NW Greenland margin. |
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