The EPICA Dronning Maud Land deep drilling operation

Frank Wilhelms , Heinrich Miller , Michael Gerasimoff , Cord Drücker , Andreas Frenzel , Diedrich Fritzsche , Hannes Grobe , Steffen Bo Hansen , Sverrir Æ. Hilmarsson , Georg Hoffmann (1, 2) , Kerstin Hörnby , Andrea Jaeschke , Steinunn Jakobsdóttir , Paul Juckschat , Achim Karsten , Lorenz Karsten , Patrik Kaufmann , Torbjörn Karlin , Eberhard Kohlberg , Guido Kleffel , Anja Lambrecht , Astrid Lambrecht , Gunther Lawer , Ivan Schärmeli , Jochen Schmitt , Simon Sheldon , Morimasa Takata , Marcus Trenke , Birthe Twarloh , Fernando Valero-Delgado , Dorothee Wilhelms-Dick

1 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
2 GLACCIOS - Glaces et Continents, Climats et Isotopes Stables

Abstract 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.

Domaines: Océan, Atmosphère; Interfaces continentales, environnement

Frank Wilhelms, Heinrich Miller, Michael Gerasimoff, Cord Drücker, Andreas Frenzel, et al.. The EPICA Dronning Maud Land deep drilling operation. Annals of Glaciology, 2014, 55 (68), pp.355-366. ⟨10.3189/2014AoG68A189⟩. ⟨hal-03213402⟩