EPICA Dronning Maud Land EDML ice core drilling protocol

• Main Authors: Wilhelms, Frank, Miller, Heinz, Gerasimoff, Michael D, Drücker, Cord, Frenzel, Andreas, Fritzsche, Diedrich, Grobe, Hannes, Hansen, Steffen Bo, Hilmarsson, Sverrir Æ, Hoffmann, Georg, Hörnby, Kerstin, Jaeschke, Andrea, Jakobsdottir, Steinunn S, Juckschat, Paul, Karsten, Achim, Karsten, Lorenz, Kaufmann, Patrik R, Karlin, Torbjörn, Kohlberg, Eberhard, Kleffel, Guido, Lambrecht, Anja, Lambrecht, Astrid, Lawer, Gunther, Schärmeli, Ivan, Schmitt, Jochen, Sheldon, Simon G, Takata, Morimasa, Trenke, Marcus, Twarloh, Birthe, Valero Delgado, Fernando, Wilhelms-Dick, Dorothee
• Format: Dataset
• Language: English
• Published: PANGAEA 2014
• Subjects: Break strength; Comment; Core length; Density; mass density; DEPTH; ice/snow; EDML; EDRILL; EPICA; EPICA-Campaigns; EPICA drill; EPICA Dronning Maud Land; DML28C01_00; European Project for Ice Coring in Antarctica; Kohnen Station; Level; Mass; Number; Pitch; lower limit; upper limit; Run; Run Date/Time; Temperature; technical; Volume; East Antarctica; Dronning Maud Land; Kohnen; Annals of Glaciology; Antarc*; Antarctica; ice core
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.841035; https://doi.org/10.1594/PANGAEA.841035

We report on the EPICA Dronning Maud Land (East Antarctica) deep drilling operation. Starting with the scientific questions that led to the outline of the EPICA project, we introduce the setting of sister drillings at NorthGRIP and EPICA Dome C within the European ice-coring community. The progress of the drilling operation is described within the context of three parallel, deep-drilling operations, the problems that occurred and the solutions we developed. Modified procedures are described, such as the monitoring of penetration rate via cable weight rather than motor torque, and modifications to the system (e.g. closing the openings at the lower end of the outer barrel to reduce the risk of immersing the drill in highly concentrated chip suspension). Parameters of the drilling (e.g. core-break force, cutter pitch, chips balance, liquid level, core production rate and piece number) are discussed. We also review the operational mode, particularly in the context of achieved core length and piece length, which have to be optimized for drilling efficiency and core quality respectively. We conclude with recommendations addressing the design of the chip-collection openings and strictly limiting the cable-load drop with respect to the load at the start of the run.