Developing a 3-D model for the Skaergaard intrusion in East Greenland: constraints on structure, mineralisation and petrogenetic models

Abstract

The Skaergaard intrusion (Fig. 1) is probably the most studied layered gabbro intrusion in the world (Wager & Deer 1939; Wager & Brown 1968; McBirney 1996; Nielsen 2004). The intrusion is c. 54.5 Ma old and was formed during the Palaeogene opening of the North Atlantic Ocean, intruding into the base of the East Greenland flood basalts. The intrusion is relatively small with a volume of c. 300 km³ (Nielsen 2004). Spectacular magmatic layering and systematic evolution in the compositions of liquidus phases and estimated melt compositions (e.g. Wager & Brown 1968) have made the intrusion the most studied example of the development of the ‘Fenner trend’ of iron enrichment in basaltic liquids (e.g. Thy et al. in press; Veksler in press).