Intermediate-depth ice coring of high-altitude and polar glaciers with a lightweight drilling system

• Published in: Journal of Glaciology
• Main Authors: Zagorodnov, V., Thompson, L.G., Ginot, P., Mikhalenko, V.
• Other Authors: Byrd Polar Research Center, The Ohio State University Columbus (OSU), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Geography, Russian Academy of Sciences Moscow (RAS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2005
• Subjects: [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology; glacier; glaciers; Ice cap; ice core; Journal of Glaciology; Alaska
• Online Access: https://insu.hal.science/insu-00375203; https://insu.hal.science/insu-00375203v1/document; https://insu.hal.science/insu-00375203v1/file/div-class-title-intermediate-depth-ice-coring-of-high-altitude-and-polar-glaciers-with-a-lightweight-drilling-system-div.pdf; https://doi.org/10.3189/172756505781829269

International audience A total of 11 ice cores to a maximum depth of 460 m have been obtained over the past 3 years from high-altitude glaciers on the saddle of Mount Bona and Mount Churchill in Alaska (designated B-C), and on Quelccaya ice cap and Nevado Coropuna in Peru. Ice coring was conducted using an intermediate-depth drilling system. The system includes an electromechanical drill (EMD) and an ethanol thermal electric drill (ETED). The EMD permitted an average ice-core production rate (ICPR) of 7.0 m h−1 down to 150 m. An average ICPR of 2 m h−1 to 460 m depth was possible with the ETED. The quality of the B-C ice cores is better than that of cores previously drilled with an EMD and ETED system. A new cutter design, drilling with a lubricant/cutting fluid and a new anti-torque assembly were tested in the laboratory and in glacier boreholes. We examine the performance of the drills in cold and temperate ice and in clean and particle-laden ice. The influence of the ethanol drilling fluid on ice-core isotopic, ionic and dust composition is discussed.