Congratulations to Bjørn on finishing his Masters.

Bjørn was supervised by Christian Tegner (ESP) and Thomas F. Kokfelt (GEUS).

Abstract:

The Vend Om Intrusion is part of the Skjoldungen Alkaline Province that forms a belt of Archean (2720-2665 Ma) intrusions in South-East Greenland ranging from pyroxenites and hornblendeites over hornblende-rich norites and monzonites, to granite, syenite and carbonatite.

The Vend Om Intrusion is a small 325 x 450 m oval outcrop of a hornblende-gabbronorite layered intrusion. The contact to the host gneiss is steep, near vertical, and is often intruded by felsic sheets up to 3 m wide extending up to 40 meters into the intrusion. The outermost, up to 50 m thick, Marginal Zone dips steeply and consists of hornblene-mela-gabbronorite. The inner Layered Series in the centre of the intrusion consists of Fe-Ti oxide-bearing hornblende-gabbronorite and shows prominent cm- to m-scale modal layering, including up to 1.5 m thick layers and irregular bodies with up to 75% magnetite and 5% ilmenite (with hercynite). Overall, the modal layering defines a concentric structure that is steeply inward-dipping.

In order to examine the magma chamber processes and subsolidus modifications for the Vend Om Intrusion, the following data are presented: Petrography and mineral chemistry of 51 samples along with whole rock geochemistry data of 93 samples, and a SW-NE transect of samples through the intrusion.