Retour des géologues, lourdement chargés

  • Laurent Geoffroy

The weather is beautiful when Vagabond is finding her way between icebergs and leaving Svartenhuk. The scientific expedition Volcabasin is finishing successfully, we are heading for Uummannaq with hundred of kilos of rocks and equipment. Laurent Geoffroy, expedition leader:

"The scientific purpose of this survey is to investigate an about 6 km thick, 50-60 million years old, volcanic field, located almost entirely above the sea level, at a continental / oceanic lithospheric (the upper 50 to 100 km of the inner Earth) boundary. This huge volcanic event was induced by a lithospheric break-up of Eocene age. This event, that divided a former unique tectonic plate into the nowadays Greenland and North American plates, occurred above an exceptionally hot upper Mantle. This specific setting is believed to bring on an unusual type of passive margin: the “Volcanic Passive Margin”. The detailed study of the lavas will allow identifying the depth and composition of the mantle source of these unusual magmas, and linking the melting event to the extensive deformation of the margin. More generally the aim of this program is to further understand the mechanisms of break up of a continental lithosphere under a particularly hot regime."